Pododermatitis is a disease of the integument of the plantar (bottom) surface of a bird’s foot. It can also spread to the dorsal (top) surface of the foot. It is caused by irritation, trauma, poor perching, or overweight. It will become progressively worse unless it is treated aggressively. There are seven stages of progression of the disease; the last is so severe that the bird’s foot might need to be amputated. Treatments consist of medical intervention in the early stages and surgical intervention in the later stages. The sooner the affliction is addressed, the more likely are the chances of full recovery.

Introduction 

Pododermatitis, commonly known as “bumblefoot,” has become a frequently seen disease in companion and aviary birds. “Pododermatitis” is a general term for any inflammatory or degenerative condition of the avian foot. Many times, birds will come into the clinician’s office for a routine annual examination, and the feet will show signs of subclinical or even more serious disease. The condition may range from very mild redness or swelling to chronic, deep-seated abscesses and bone destruction. If caught in the early stages, the underlying, predisposing factors may be corrected, and the disease will often be reversed.

1. Which species of birds are most at risk for developing pododermatitis?

Pododermatitis has been reported in many species of birds, but on a clinical level, it is particularly problematic in captive birds of prey, Galliformes (chickens and turkeys), Anseriformes (ducks, geese, and swans), waders, penguins, and many Psittaciformes (parrots). Of the psittacines, Amazons, budgerigars, and cockatiels are particularly vulnerable to this disease. The condition is frequently described in captive raptors, but it may occur in any avian species, including canaries and finches⁴. Because footpads are present in psittacines more so than in other species, birds in the parrot family are more likely to suffer from this disease.²²

Figure 1. Pododermatitis at Grade II on the feet of a finch(image courtesy Tamara Lowes; used with permission). Note the length of the nails. Long nails have a tendency to catch on fabric and other things in the environment, thus causing trauma to the sores on the feet and forcing the feet to stand in unnatural positions.

Figure 2. Pododermatitis at Grade IV on the feet of a finch, plantar surface (image courtesy of Tamara Lowes; used with permission).

Figure 3. Stage III Pododermatitis. The bands should always be removed in birds if possible. They can create additional paid and damage to the feet. The sore on the tarsometatarsus (heel) of the foot gets additional stress and has become infected (image courtesy Aquarium Store Depot, https://aquariumstoredepot.com/blogs/news/bumblefoot-in-birds)

The scales on the feet are composed of highly keratinized epidermal (the outermost layer of skin) tissue, and this tissue covers the lower leg (podotheca) and foot. The nails/claws are formed by plates of strong, keratinized tissue that enclose the terminal phalanx (last toe bone) of each digit.  It is this keratinized tissue on the plantar surface of the feet that gets quickly worn away when the foot becomes irritated and sore.²²

Birds most at risk for developing pododermatitis are obese birds having excess pressure placed on the feet; aged, sedentary and disabled birds; birds with limited mobility; chronically ill birds; and those with any kind of immune system weakness.²¹

Figure 4. Grade III pododermatitis in a Ringneck Parakeet. This is a result of inadequate perching. The perch appears to be too large, and the weight has been born by the back toes (image courtesy Pin by Tria Connell on Bubu’s Feet | Parrot, Bird, Animals). https://www.pinterest.com/pin/402509285443794473/https://www.pinterest.com/pin/402509285443794473/

1.1 What are the risk factors for developing pododermatitis?

• Previous foot or leg injury
• Hard, muddy, flooded, uneven, or rough floor surfaces
• Damp or unsanitary bedding litter
• Vitamin A deficiency
• Overweight
• Excessively dry skin
• Lack of activity
• Excessive activity due to fighting among flock members or guarding behavior (Mainly in chickens)
• Leg or conformation abnormality
• Improperly designed perches (plastic, sharp corners, incorrect diameter)
• Excessive accumulation of feces
• Poor diet
• Overgrown toenails

(Poultry DVM Bumblefoot in Chickens 2021 file:///L:/Pododermatitis/Bumblefoot%20in%20Chickens.html)

1.2 Causes or predisposing factors behind the development of bumblefoot

• Obesity and inactivity, which put more weight on the feet than it can handle. (Poultry DVM Bumblefoot in Chickens 2021 file:///L:/Pododermatitis/Bumblefoot%20in%20Chickens.html)
• Improperly designed perches: perches that are too small or too large and have no variety of diameter; those that are hard or uneven; dowel or hardwood surfaces; any rough-textured perches such as warming perches, and all concrete perches, plastic perches, those covered in sandpaper or burlap, perches with sharp corners, perches that are too narrow, and perches or spirals made of sisal. (J. Miesle)
• Hard, coarse floor surfaces, such as cement. These are common in aviaries, zoos, and breeding facilities. In poultry, floors may have hard, muddy, flooded, uneven, or rough surfaces. (Poultry DVM Bumblefoot in Chickens 2021 file:///L:/Pododermatitis/Bumblefoot%20in%20Chickens.html)
• Poor nutrition and Vitamin A deficiency. Birds need vitamins added to their food. (Some vitamins, such as ©Avi-era (Lafeber) may be added to the water.) If they are on a pelleted diet, reduce and eliminate the pellets. Extra vitamins should not be given until the pellets are eliminated. They should be fed natural, non-pelleted diets consisting of fruits, vegetables, greens, some people foods, and seeds. Sunflower and safflower seeds may be given sparingly. They are high in fat and can lead to hepatic lipidosis (Fatty Liver Disease).  (J. Miesle)
• Poor husbandry: damp, unsanitary bedding and all substrates. An accumulation of feces and an overall unsanitary environment caused by substrates will lead to fungal and bacterial diseases and are a haven for parasites. Plain newspapers, paper towels, or other paper sources are the only things that should be used. Rope perches and natural wood perches wrapped in fleece or cohesive bandage tape to prevent sores are best. (J. Miesle)
• Overgrown toenails
• Stress, hypothyroidism,²¹ and poor hepatic (liver) dysfunction ⁵
• Severe poxvirus lesions with secondary bacterial infections ²¹
• Trauma, particularly among poultry:
  • Fighting among flock members,
  • Previous leg or foot injury leading to crippling
  • Frostbite injuries and thermal burns
  • Leg or conformation abnormalities
  • Cracks or worn-away areas and discoloration of the skin
  • Damage to the plantar surface of the foot. Injuries cause lesions to develop on the plantar surface of the phalanges or on the tarsometatarsus. Plantar decubital ulcers (pressure sores) are common. ²⁰

(Poultry DVM Bumblefoot in Chickens 2021 file:///L:/Pododermatitis/Bumblefoot%20in%20Chickens.html)

• Concurrent illnesses or conditions causing an abnormal standing position
  • Arthritis. Pain in the joints causes the bird to walk on the sides of his feet; in this case, the toes bear most of the bird’s weight.
  • Subdermal infiltrate swelling. The bird in Figure 4 suffered from mycoplasmosis as a result of a staphylococcus infection. He was unable to stand due to a nidus (pocket of bacteria) on the planter surface of the foot.
  • Thickened pads on the bottom of the foot due to scar tissue or previous wounds which have been covered with these pads.
  • Walking on the “heel” of the foot or the side of the foot due to swelling on the toes or center of the plantar surface of the foot. (J. Miesle)

2. The importance of providing the correct perching for the birds

The following perches are known to be detrimental to the plantar surface of the feet and cause pododermatitis in the feet and arthritis in the leg joints. Any of these can be wrapped with fleece or cohesive tape/bandage wrap to vary the diameter of the surface; however, most are round and need to be wrapped with high and low placement of the cushioned wrap.

Many people use Vetrap, but the author has found this tape to collect dirt very quickly, and it is so sticky many birds will not stand on it. Cohesive tape and fleece are better choices of products.

For birds with less serious pododermatitis, wrapping the perches with fleece will give the bird soft surfaces to stand on. For more serious cases, the birds should be kept on towels in bins until they have healed sufficiently to return to the cage. Once there, the perches should be wrapped in fleece. Purchase at least half a yard of fleece and cut several 1-inch strips from it. Wrap the perch from the place closest to the cage bars, overlapping the fleece by half the strips. When you have reached the end of the perch, use a twist tie to wrap around the fleece and hold it on. It will need to be washed at least twice a week, so have extra strips ready to replace them. They wash well in the washing machine. (J. Miesle)

2.1 Perches that are harmful to the bird’s feet and leg joints.

Figure 5. Plastic perches. These are usually too small for the bird, causing the bird to grip too tightly to stay balanced; they also create pressure sores (image courtesy ebay.co.uk).

Figure 6. Kroger’s Tender Tape. This is a cohesive tape/bandage that wraps the perch well without being sticky. It will get dirty, so it must be changed at least once a week. It comes in white and tan. Choose the white tape so you can see soiled areas more easily and change the tape. A similar product can be purchased at the pharmacy with the name “cohesive tape” (image courtesy J. Miesle).

Figure 7. Rough-textured perches. These include cement, calcium, sandpaper, or warming perches. They irritate the plantar surface of the foot and cause sores and arthritis; they do nothing to keep nails short because the nails do not touch the perch (image courtesy K&H Pet Products Bird Thermo-Perch).

Figure 8. Concrete perches should never be used. They irritate the plantar surface of the foot and cause cuts and tears (image courtesy Kathson Bird Perch Parrot Stand Cage Accessories Natural Wooden Stick Paw Grinding Rough-surfaced). 

Figure 9 Sandpaper perch covers for dowel perches. Not only do they not keep the nails filed, but they also cause sores on the feet and arthritis in the legs. They irritate the skin on the plantar surface, causing small cuts and sores. The owner can remove the sandpaper covers and wrap the perch with cohesive wrap or fleece, making sure to vary the diameter of the wrapped surface. Sandpaper covers also have a tendency to slip on the perch, causing the bird to grip too tightly to maintain balance, leading to arthritis (image courtesy Penn Plax Sanded Perch Covers for Small Birds).

Figure 10. Round dowel perches. These will place all the bird’s weight in the same place, and, because they are slippery, they are difficult for the bird to grip, forcing him to grip tighter all the time. Any perch that can become slippery puts additional strain on the muscles of the leg and foot to stay balanced (image courtesy Prevue Pet Products Birdie Basics Wood Perch 10 in).

Figure 11. Hardwood and softer natural wood perches and platforms offer a variety of textures and diameters. Even these can be slippery, causing the bird to grip too tightly. And they are too hard for the bird’s feet. They can be wrapped with cohesive tape or fleece strips for birds with pododermatitis (image courtesy Ebay).

2.2 Platform perches made of wire and wood

Platform perches come in a variety of sizes, shapes, and compositions. They can be found in wood, chrome, and coated wire. They can be a problem if they are not covered in fleece or flannel for all birds, but particularly for the bird with bumblefoot. They should be covered with several layers of soft, padded material, such as a towel, flannel, or fleece cut slightly larger than the platform perch and with a stack of paper towels under the fleece for comfort. These coverings may be held down with binder clips for thinner perches or C-clamps for thicker ones  Never let any bird stand on open wire, as on grids on the bottom of the cage. Cover all wire with paper towels or cloth towels.

Figures 12. Flat wood perches. These should be covered with at least 2 layers of fleece. These perches can be secured with binder clips or C-clamps. For birds who do not have pododermatitis, paper towels may be placed on top of the fleece for easy cleanup (image courtesy Pevor Wooden Parrot Bird Cage Perches, Amazon).

Figure 13. Another type of platform perch is the flat wire perch (image 12 courtesy Platform Perches – Just for Pets). These and the wood platform perches are wonderful for the birds, but they too must be covered with flannel or fleece since the wire is very damaging to the feet. The fleece can be secured with binder clips. The owner can put paper towels on the cloths to protect the surface from droppings and make for easy cleanup. Birds with pododermatitis should be standing only on fleece.

The perches should be of various textures, sizes, and shapes so the bird is not standing on the same plantar surface all the time. Natural perches covered in strips of fleece, and rope perches are best. Oval or flat perches attached to the side or corner are better than round ones all the same size.

You can purchase flannel and fleece fabric from any fabric store, places like Walmart, or online. Cut several layers a little larger than the platform to fit and hang over the sides. Do not use paper towels or other types of fabric on perches for birds with bumblefoot due to their rough texture and slipperiness; in addition, both could be easily ingested. When the feet have improved, loose paper towels may be placed on top of the secured ones for easy cleanup. These cloth towels must be laundered daily or whenever soiled, so you will need to cut several. A half-yard or yard of fleece will give you many pieces to work with.

Perches that are both too hard, such as Manzanita perches, and too smooth, such as dowel and plastic perches, sharp-cornered perches, rough pedicure perches, sandpaper and rough-textured/concrete perches should be removed and replaced with rope perches and natural wood perches. Hard perches should be wrapped with a cohesive material such as Kroger’s Tender Tape® or other cohesive tape which can be purchased at a drug store, or wrapped with one-inch strips of fleece. This will provide both padding and changes in diameter when the material is wrapped at varying intervals and thicknesses. Natural perches with different circumferences and textures are good but should be covered with cohesive tape or fleece strips. Birds should be encouraged to perch in different places and varying surfaces. This can be achieved by placing food and water dishes in different areas and changing the position of the favored perches.²

Birds will choose a favorite place within the cage to perch, so whatever perch is in that place is the one they will choose to rest. The place is more important than the kind of perch to a bird; take note of that and put the softest perches there. J. Miesle

2.3 Perches that are beneficial for the birds’ feet and legs.  

Figure 14. Booda rope perches (image courtesy JW Comfy Perches for Birds).

Rope perches are available at some pet stores under different names. These are good for birds who are not afflicted with pododermatitis or have only Grade 1 pododermatitis. These come in various diameters and lengths and also in spirals. They give the feet the soft, comfortable perching they need when they’re on their feet and have minimal flying time. They must be removed and cleaned regularly so the bird is not standing on fecal material or food debris. When they become shredded, they must be replaced. Watch the bird carefully for signs he is chewing and possibly consuming the fibers on the perch. If he is doing that, remove the perch and replace with a natural wood perch covered in fleece. If the bird chews on that, provide only soft, natural wood perches.

Figure 15. Padding perches with foam helps prevent bumblefoot as well as aiding healing in afflicted birds. Be sure to watch for signs of the bird chewing on these. If he is consuming the pieces, remove them and use wood perches (images courtesy Hagen Avicultural Research Institute; used with permission; Burgmann, Symptoms and Treatment of Bumblefoot). 

3. Symptoms of bumblefoot in birds

• Dark, circular scabs on feet
• Redness, shininess, and small, red sores on the plantar surface of the foot
• Abrasions, cuts, tissue damage on the bottom of the foot
• Swelling and thickening of the skin
• Lameness and swollen joints in the feet or toes
• Reluctance to walk, stand, or grasp normally with one or both feet
• Ulcers on the soles of the feet^{2, 21}
• Shifting of weight from one foot to the other
• Picking at the sores on the feet

3.1 Means of infection

There are two ways infection can set it:

• Through a puncture in the skin of the base of the foot (a talon, a thorn, or a foreign object)
• Through pressure sores (decubitus ulcers) on the bottom of the foot.⁹

Figure 16. Healthy tissue in a cockatiel. Note that the nails are being kept short, but not too short. This is important; the bird could catch his nails on fibrous materials and slip and fall (image courtesy J. Miesle).

3.2 Punctures to the skin leading to bacterial infections

Infections may occur when penetrations, such as cuts and sores, happen. Bacteria such as Staphylococcus aureus may enter the skin and cause damage if it has not been observed and treated. ² Once the wound becomes serious, oral antibiotics, anti-inflammatories, and topical antibiotics will be needed.²  Celebrex (celecoxib) is the best medication for birds for pain and inflammation.  (J. Miesle)

Systemic infections that result in decubital lesions or death can occur secondary to bumblefoot and are caused by virulent strains of S. aureus. This bacterium is frequently isolated from the lesions, but the birds will usually not respond to antibiotic therapy alone. These bacterial lesions may quickly lead to digital necrosis and gangrenous dermatitis. Staphylococci are by no means the only bacteria that might be recovered from diseased tissue: E. coli, Corynebacterium species, Pseudomonas species, and yeast are frequently cultured from the lesions.¹⁰

3.3 Decubitus ulcers

Decubital ulcers are open sores on the skin, often covering bony structures. Pressure sores occur because of uneven weight-bearing that leads to damage and devitalization of the skin. Both of these lead to bacterial and/or fungal infections of the skin. Once the process begins, a series of changes is initiated which will eventually damage the tendons of the foot and spread to muscles, joints, and other tissues. It can become a chronic disease, affecting the aortic and mitral valves of the heart and causing endocarditis (inflammation of the heart valves), vascular insufficiency (poor blood flow), lethargy, and dyspnea (labored breathing).⁹
4. Additional factors contributing to the development of pododermatitis

4.1 Malnutrition

In Psittaciformes and Passeriformes (songbirds), most lesions are believed to be the result of malnutrition. Poor nutrition causes the skin of the foot to become dry, flaky, and hyperkeratotic (developing a thick, outer layer of keratin on the skin). It is thought that dry, hyperkeratotic skin on the feet changes the mechanics of weight-bearing on the metatarsal pads. This condition is also precipitated by environmental deficiencies and systemic disease.⁴

Sunflower and safflower seeds have a high-fat content. Too many in the diet can lead to obesity in parrots and other pet birds. Traditionally, parrot diets have consisted of a mixture of seeds, with sunflower seeds being an important part of most diets (50% of the content of a sunflower seed is fat). The increased fat taken on by birds leads to Fatty Liver Disease or Hepatic Lipidosis. Over the last decade, there has been an increase in the number of parrot owners who feed their pets commercial pellets; but this is also not a perfect alternative. Pelleted food contains more fat and protein than the amount most parrots need, and the oils added to the pellets (usually palm and coconut oils) may predispose birds to atherosclerosis (fat deposits in arteries). The heavier the bird, the more weight and pressure it puts on its feet, resulting in the development of pododermatitis. This is aggravated by a lack of flying; birds do not put pressure on their feet while they fly, so birds that do not fly are more predisposed to pododermatitis and obesity.¹⁶

The best diet for birds is one that is high in fruits, vegetables, greens, some people foods, and a moderate number of seeds (except sunflower and safflower.) Seeds contain important Omega 3,6 fatty acids which protect the skin and internal organs. (J.Miesle)

See Appendix B, p.50,  for a list of foods that are nutritious for birds.

4.2 Vitamin A Deficiency

Some forms of pododermatitis are caused or exacerbated by Vitamin A deficiency. Birds that eat only seeds are susceptible to it since seeds are typically low in Vitamin A. This vitamin promotes appetite and digestion and also increases resistance to infection and to some parasites. The most obvious sign of a Vitamin A deficiency is a feather stain above the cere (the fleshy area which contains the nares or nostrils). The staining of the feathers above the cere reflects a discharge from the nostrils. Subtle differences may be seen as far as the color intensity of the cere and feathers and the overall condition of the plumage are concerned. A bird deficient in this vitamin may have pale, rough-looking feathers that lack luster. The cere may look rough instead of smooth, and you may see an accumulation of a yellow, dry scaling on the sides of the beak.²

Vitamin A deficiency weakens the epithelium (the thin, top layer of skin) of affected birds. Pressure sores, pressure ulcers, or decubitus ulcers occur when the bird is in the same position for a long period of time; the result is uneven weight-bearing. The ulcers are localized injuries to the skin and/or underlying tissues that usually aid blood flow to the soft tissue. The constant friction from the wrong types of perches can pull on blood vessels that feed the skin. Decubital ulceration on the plantar surface of the feet is common in older, obese, nutritionally deficient psittacines.²⁰

4.3 Limited flying opportunities

Restricted flight opportunities lead to inactivity and obesity, and these produce excessive pressure on plantar surfaces, the toe pads, and the tarsometatarsus. Erosion occurs, and ulcers and staphylococcal infections develop.²⁰

Figure 17: Grade I lesions. Note the shiny area on the foot pad (image courtesy Hari; used with permission).

4.4 Secondary disease

“Pododermatitis can also take place secondary to infectious or parasitic diseases, penetrating foot wounds or leg injuries that affect normal gait and weight distribution. Epithelial damage that arises secondary to asymmetric weight-bearing on the metatarsal pad causes reduced circulation, microepithelial damage (microcysts: very small, round vesicles containing fluid and cellular debris), local impairment of the immune system, and ultimately, invasion of opportunistic pathogens.”¹⁹

For companion birds, raptors, and other wild birds, pathogenic bacteria introduced at traumatized sites may lead to abscessation (formation of abscesses), osteomyelitis (bone infection), or joint changes.⁹

See Appendix A, p. 42, for more information on the treatment of raptors

4.4.1 Arthritis

Septic arthritis may also play a part in the development of pododermatitis. Joints may become infected through a direct, penetrating wound or through the hematogeneous route (spread through the bloodstream). Although the infection may be controlled, a decrease in the range of motion of the joint usually occurs.¹¹

Figure 18: Grade II lesions. Notice the wearing away of the skin on the back toe, continuing into the central pad of the skin (images courtesy Hagen Avicultural Research Institute; Burgmann: Symptoms and Treatment of Bumblefoot; used with permission).

Figure 19: Grade III lesions. Note that the bird is putting his weight on the outside of the foot, causing stress on that toe. This skin on the other toe is wearing away, and the lump on the side of the foot is thickened and swollen (images courtesy Hagen Avicultural Research Institute; Burgmann: Symptoms and Treatment of Bumblefoot; used with permission).

4.5 Contact with tobacco products

Many affected birds belong to cigarette smokers. Passive inhalation of cigarettes, cigars, pipe smoke, e-cigarettes, marijuana, and other types of airborne drugs not only causes ocular and respiratory disease in birds but also damages the integument. (Marijuana exposure also causes severe depression and regurgitation in birds and should be strictly avoided.) Pododermatitis has been observed in birds handled by smokers as the nicotine residues on the hands of smokers will cause this irritation. If minor, the lesions may spontaneously resolve when the client stops smoking; cleans all the furniture, walls, curtains, and cages; only smokes outside; washes his hands and arms and changes his clothes before handling the bird.⁸

The feet and legs should be uniform in texture and color. The feet should have prominent scale patterns on the dorsal and plantar surfaces. Changes that result in the smoothing of the plantar foot surface can instigate chronic and severe foot and leg lesions. One of the common etiologies of foot abnormalities is contact with nicotine sulfate from the hands of cigarette smokers. The feet are particularly vulnerable to fungal diseases due to smoking toxicity.⁸ Macaws (and other birds with bare cheek patches) may suffer similar dermatitis on their cheek patches following repeated contact with a smoker’s hands and arms and the smoker’s environment.⁸

When toxic particulates and gases in the air assault a bird’s respiratory system, skin, and feathers, feather destruction and plucking result. Heat causes the smoke to rise; then, when it cools, gravity brings it back down. The toxins land on the birds, their perches, their cages and cage bars, toys, and food. It is also on the smoker’s hands, arms, clothes, and any other exposed skin— even the hair. If the smoker’s hands are coated with chemicals from holding the cigarette, it is easily transferred to his bird. In one case, an Amazon, who became very sensitive to chemical exposure, began mutilating his feet. The clinician determined the cause to be his perches which were covered with residue from cigarette smoke.¹⁴ Even if the smoker takes these precautions, his clothes, the furniture, rugs, curtains, and perches inside and outside the cage will be covered in smoke and ash. It is best for the smoker to stop smoking and have his home professionally cleaned. (J. Miesle)

Figure 20. Grade IV bumblefoot in a parakeet (images courtesy Burgmann. Symptoms and Treatment of Bumblefoot, Hagen Avicultural Research Institute; used with permission). 

4.6 Contact with strong cleaners and disinfectants

These may also be responsible for irritation and dermatitis on the feet. Cleaning liquids should always be dry and rinsed before the bird walks on the cleaned surface. Cleaning products should be carefully chosen so that chemical irritants are not used.⁸ Air freshener plug-ins and sprays should never be used around birds. They also damage the respiratory system.¹⁴ (The best cleaner is white vinegar and water: 2.5 cups white vinegar to 1 gallon water.) J. Miesle

4.7 Allergens

The allergy syndrome appears to be more common in the spring, suggesting a seasonal allergy. Seasonal recurrences of the lesions may be prevented by the oral administration of prednisolone about one month prior to the time that lesions typically occur.⁸
5. Avian Veterinary Examination by the Clinician, both at home and at the Physician’s Office

5.1 Physical exam

A bird’s skin is very delicate, and the skin of the foot reflects the condition of the rest of the dermis. The plantar surface of each foot should be checked daily by the owner, and the clinician should inspect the feet at the bird’s visits. Both owner and clinician should note the condition of the metatarsal and digital pads and look for loss of definition of the epidermis (seen as a shiny, reddened surface), swelling, erosions, ulcers, and scabs. Birds that are crippled from an injury or genetic defect are prone to developing sores on one or both feet due to the stance they must assume. The owner and practitioner must be observant for signs of pain or discomfort.⁶

If a bird is lame on one leg, he must bear his weight on the unaffected leg; this, in turn, can lead to pressure necrosis, infection, and subsequent pododermatitis on that foot as well. The clinician should always examine the other leg and foot closely when any lameness occurs. A complete examination, including radiographs, may require that the bird be anesthetized to reduce stress on it.⁶

Figure 21. Grade V lesions on a cockatiel with arthritis (image courtesy of Julie Burge; used with permission). Note that there is fecal matter on the feet; this can cause additional infection in the already infected skin. 

Figure 22. Grade VI pododermatitis in a parakeet. Note that the plantar surface is covered in ulcers, scabs, and pressure sores from being on the wrong kinds of perches. Some areas of the toes are also impacted (image courtesy Burgmann, Symptoms and Treatment of Bumblefoot, Hagen Avicultural Research Institute; used with permission). 

Figure 23. Grade VI pododermatitis in a cockatiel. Fecal matter is visible on the pads of the feet and toes. The areas impacted by the disease are deeply imbedded in the skin and will bleed easily when the bird is trying grip the perch (image courtesy David Perpinon; used with permission).

5.2 Testing of the skin

Bacterial samples will be taken and evaluated at a microbiology lab in order to isolate the offending organism. An antibiotic sensitivity test may help determine the best course of antibiotic treatment to rid the bird of this condition or to manage it in the case of a chronic issue. A blood sample will be taken to check for other possible health conditions. X-rays will reveal signs of infection and will indicate any areas on the joints or bones where there’s been erosion or other damage.²¹ Skin scrapings or fine-needle aspirates may also be performed. (J. Miesle)
6. Clinical Grades of Pododermatitis

Hagen Avicultural Resource Institute definitions: The following classification grades have been lifted directly from the HARI institute website. (All are used with permission from HARI).

“A classification scheme grading from early clinical signs and progressing to severe lesions has been established. The clinical progression of the disease varies based on the species and the factors that contributed to the infection.”

Clinical Grades of Pododermatitis⁵

Grade I: Desquamation (shedding of the epithelial or skin tissue) of small areas of the plantar foot surfaces is represented clinically by the appearance of small, shiny pink areas and peeling or flaking of the skin on the legs and feet. Initial lesions are recognized as hyperemia (excessive amount of blood). Flattening of the skin of the digital and metatarsal pads is visible. These are the sites of maximum weight-bearing. (Thinning of the plantar surface of the foot with some reddening).

Grade II: These lesions progress if untreated, and bacteria invade the subcutis, resulting in a scab and mild swelling. (The subcutis is the deeper layer of the dermis, containing mostly fat and connective tissue). Smooth, thinly surfaced, circumscribed areas appear on the plantar metatarsal pads of one or both feet with the subcutaneous tissue almost visible through the translucent skin. No distinct ulcers are recognized. (The thinning of the plantar surface of the foot has progressed to the point that subcutaneous tissue such as tendons can be seen through the skin).

Grade III:  The sores progress to form a caseous (having a cheese-like texture) abscess with marked swelling and pain. Ulceration of the plantar metatarsal pads occurs, and in some birds, a peripheral callus may form. Ulcers form on the soles of feet with callouses forming around the edges of the lesions. Some pain and mild lameness are present.

Grade IV:  Infection of the tendon sheaths develops. Corresponding cellulitis tracks toward the intertarsal joint and the digits along with flexor tendon rupture. There is a necrotic plug of tissue present in the ulcer. Most species with ulcers and accumulation of necrotic debris exhibit pain and mild lameness. (Necrosis refers to cell death; the tissue turns black).

Grade V:  Swelling and edema (cellulitis) of the tissues surround the necrotic debris. The digits of the foot may also be edematous (holding fluid). Necrotic debris starts to accumulate in the metatarsal area, indicating infection of the tendon sheaths. Severe lameness is common, and the entire metatarsal pad may be affected. This is generally a chronic lesion leading to osteoarthritis and septic arthritis of the tarsometatarsal-phalangeal joints. Cellulitis surrounds the area of necrosis, and the foot can be swollen with fluid. Tendon and metatarsal pads become infected; pain and severe lameness are present.

Grade VI: Necrotic tendons are recognized clinically as the digits swell and the flexor tendons rupture. Ankylosis and nonfunctioning digits are usually present in recovery.  (Ankylosis refers to the stiffness of a joint due to abnormal adhesion and rigidity of the bones of the joint, which is usually the result of injury or disease). The digits are swollen and the necrotic flexor tendons on the plantar surface of the foot rupture. Even with treatment, non-functioning digits and joint fusion will be present.

Grade VII: Osteomyelitis develops. This is a bacterial bone infection leading to the destruction of the bone itself. Bone infection can progress to systemic infection and death.

Figure 24. Comparison of a healthy plantar surface on the right and Grade VII severe case of pododermatitis on the left (image courtesy Lauren Thielen; used with permission).

6.1 Grading discussion

Grades I to III lesions are common in Psittaciformes and Passeriformes that are on all-seed or over-supplemented fruit and vegetable diets, are overweight, have no exposure to sunlight, or are kept on improper perches. With proper husbandry and nutrition, most cases recover with little medical intervention. The type of substrate and the size, shape and covering material of the perches may all influence the bird’s weight distribution on the toes and metatarsal pads. These affect the amount of skin wear on the plantar surface. For example, a perch that is too wide and flat may cause excessive weight-bearing on the toe pads, while one that is too small may cause excessive weight-bearing on the metatarsal pads.⁵

Early grades of pododermatitis show loss of the scale pattern on the foot, redness, and mild swelling. This damage can often be treated with topical softeners, improvement of the diet, and modification of the bird’s environment. Reversal is possible when the disease is at Grades I and II. The earlier the disease is caught, the more effective the treatment will be. The prognosis for the full recovery of lesions of Grade I to III is usually more favorable than Grades IV to VII lesions.⁵

Grade III bumblefoot is common in older, inactive birds that are fed inadequate diets. Early lesions (smoothing of the plantar foot surface) and hyperemia (an excess of blood in the vessels supplying an organ or other part of the body, Wikipedia) are frequently missed, and the birds are often not seen by the clinician until this grade. Some birds are not presented until they exhibit a non-weight-bearing lameness. This disease is dynamic and may move from one grade to the next quickly.⁵

Damage to the feet in Grades IV to VII usually requires surgical intervention since the changes that lead to infection also reduce the ability of antibiotics to be effective. Debridement of the wound, surgical removal of damaged tissues, and wound bandaging are treatments that are frequently used.⁵

Older budgerigars and cockatiels (5-10 years old for budgerigars and 10-20 years old for cockatiels) may have Grade V or VI lesions if precipitating factors are not corrected early. Bone changes and osteomyelitis may be present. Later grades are very serious and life-threatening. Since the development of antibiotic-impregnated beads, veterinarians can treat later grades more successfully than they could before. Amputation is sometimes necessary. Prosthetics may be used for birds such as ducks that cannot survive with only one good foot.⁵

6.2 Case Study: Pododermatitis caused by a parasitic bacterium

The cockatiel, Chico, is one of the author’s birds. In January of 2022, this bird became ill with

several severe symptoms. He developed a yellowish, raised area on the dorsal area of his one foot, and a sore area on the plantar metatarsal surface of the same foot. The bird was diagnosed with Mycoplasma synoviae, “a Gram-negative parasitic bacteria responsible for causing respiratory tract disease and synovitis” (inflammation in the lining of the joints). (Merck Vet. Manual) (J.Miesle)

Figure 25. Spring, 2022. The staphylococcus synoviae infection which began the disease, causing the yellow swelling on the top of the foot and the crusty yellow on the formation of the nidus pocket. “The skin is showing some scabbing and flaking, as though it were irritated. The deeper tissues appear to be mildly hyperemic and there is a yellowish infiltrate in the tarso-metatarsal phalanx joint.” (Bob Dahlhausen) (image courtesy J. Miesle).

Figure 26. Subdermal infiltrates caused a nidus (pocket of infection) on the plantar surface of the foot which made the bird shift his weight onto the side of the foot and the tarsometatarsus (heel). After the nidus was resolved, the skin on the plantar surface barely covered the bones; this led to a pad of tissue developing. Because the pad was so large, he was forced to walk on the side of his foot and toes. Arthritis set in because of his unusual limp and gait (image courtesy J. Miesle).

The nidus pocket formed on the plantar metatarsal surface of the foot. The scab that resulted during treatment is covering the nidus hole. The pocket is deep under the thin scab and will bleed if the scab is disturbed. The nidus goes all the way down to the bone and is the result of the S. aureus infection. Infections and diseases can cause swelling, scabbing, and yellow crusting in the feet resulting in pododermatitis (image courtesy J. Miesle).

Figure 27. There were many ailments due to mycoplasma synoviae. It was very painful for the bird. He had very little appetite, and as a result, he lost weight. In addition to the nidus on the center of the foot, more nidi appeared on the toes. These were the first to be resolved. The skin on the toes became thin and fragile (image courtesy J. Miesle).

Black arrow: previous nidus area in center

Figure 28. Nov. 2023. The nidus area after some healing has taken place. The sore area is divided into three sections and remains that way to this date. In order to reduce the size of the pad, the author has been massaging the area twice a day with Aloe Vera Gel. This will continue as long as the bird lives. The author uses Aloe Vera Gel for Sensitive Skin from Walgreens. A small amount is mixed with water or distilled water and stirred until a thin gel is made. It is stored in a small container on the shelf (image courtesy J. Miesle).

7. Treatments for pododermatitis

Perching, cleanliness, and nutrition need to be addressed.

• The cage must be kept scrupulously clean using an antibacterial cleaner once a week or more often if it needs it. Clean all areas daily and watch for droppings and food debris as these need to be cleaned immediately.
• Nutrition: If the bird is on pellets, reduce and/or eliminate them. Replace them with fresh fruits, vegetables, some seeds (not sunflower or safflower as these are high in fat and can lead to Fatty Liver Disease), people foods, seed supplements. Pellets are hard on the kidneys and contain high levels of fat.

If the owner does not have an avian veterinarian, he may contact the author for recommendations. He may utilize the following instructions. If he does have an avian veterinarian, these instructions may be used in addition to those given by the avian veterinarian.

Figure 29. Grade II on right foot, Grade III on left (image courtesy Maria Molina-Gacal; used with permission

Figure 30. Grade V pododermatitis (image courtesy Maria Molina-Gacal; used with permission).

7.1 Treatment of the lesions for all grades

1. Clean the feet with antibacterial soap and rinse and dry well; apply and massage in the following creams. There are two prescription creams that you can get from your avian veterinarian: Gentamicin Sulfate Cream (©Perigo or ©G&W), and Neomycin and Polymyxin B Sulfates and Bacitracin Zinc Ophthalmic Ointment, USP (©Bausch +Lomb). These may be alternated, and you might eventually find one works better than the other. Alternate these with Aloe Vera Gel for Sensitive Skin from Walgreens. See next paragraph. Ask your veterinarian for recommendations of other ointments or creams you might use. If you are unable to acquire these creams, use the triple antibiotic cream and ointment from the pharmacy.

Alternate or additional topical therapy if the prescription creams cannot be purchased: Aloe Vera Gel for Sensitive Skin from Walgreens (or a similar gel). Put a small amount in a very small container and add a little distilled water; mix until you get a medium-gel consistency. Begin to massage the feet with a small amount of triple antibiotic ointment, such as Neosporin, followed by the Aloe Vera Gel. Do this treatment two or three times a day. It is available online from Walgreens. Do not use aloe vera plant liquid. It is not sterile and is not as effective as the gel. The addition of VetOmega is highly recommended to add strength and healing to the skin of the feet. See Section 9.5.2 for more information on this product.

2. Keep the bird on fleece-covered perches for a long time, at least until the feet are completely healed and possibly longer, since some birds have a relapse of the condition. Make sure you remove the fleece strips twice a week and replace with clean ones. They are washable.

3. If the bird cannot balance well and shows discomfort, place him in a storage bin on several soft towels until his condition improves. Put his food, water, and toys in the bin with him. If he’s flighted, cover with a framed piece of aluminum screening or some other type of open covering. When he’s out of the cage or bin, keep him on soft, clean surfaces at all times. You can put soft towels on the surfaces the bird walks on, such as the top of the cage or on any play areas. Keep him off the floor and all hard surfaces as much as possible.

7.2 Additional information concerning treatment for less severe cases

Less severe cases (Grades I and II) may be treated with a combination of environmental and medical methods. Correction of the underlying predisposing factors will often reverse this disease process.

• Take the bird to the avian veterinarian immediately. More severe lesions (grades III to VII) need to be cared for more aggressively. He will need to determine the extent of the damage to the feet and guide you in their healing. If the veterinarian wraps the feet, find out how often you need to bring him back to have them treated and rewrapped, or ask him to let you change the bandages there so you can do it at home. (If you do not have an avian vet, contact the author so she can help you find one.) Follow the rest of the recommendations below. Do not use a heating pad! Get a prescription for Celebrex (celecoxib). Do not use meloxicam; it is not as effective as Celebrex and can cause digestive difficulties.
• Make needed changes in diet with the addition of vitamins containing Vitamin A.

See Appendix B, p. 50, for advisable food choices for these and all birds.

Less severe cases may go back to rope or natural wood perches when the feet have healed. Perches should be soft. Rope perches are good for general use, and wood perches should be covered with cohesive tape/wrap. Vetrap is undesirable since it is sticky and holds dirt. Cohesive tape/bandage (white) will make it easier for the owner to notice the dirt and change it more often. It is not sticky, and white wrap will show the dirt more easily so the owner will be more likely to change it more often. Never use sisal perches, spirals, toys, or any other type of product. It will damage the feet and can be easily ingested, causing crop impaction.

See Section 2 for descriptions of perches that should not be used for any birds, but especially the bird with pododermatitis.

Figure 31. Stage V Pododermatitis. This lesion bled before it was seen by the avian vet and during treatment (image courtesy Diane Snuggles Hut Larson; used with permission).

7.3 Information for the treatment of more severe cases

• For birds with more severe pododermatitis, the perches should be wrapped with strips of fleece and changed several times a week. Observation will let the owner know when they need to be changed. Be careful to get the right diameter of perch for your species of bird. They will be larger as long as the fleece strips are on them. Buy at least 1 yard of very soft fleece. Wrap all perches with overlapping, 1-inch strips of fleece held down by short pieces of twist ties on the ends of the perch. Rope perches and natural wood perches should also be wrapped in fleece for the more severe cases. You can wrap any rough-textured perches and dowel perches with fleece. Eventually you will want to remove those and replace them with rope and natural wood perches, although for severe cases, all perches should remain covered in fleece strips permanently due to the probability of relapse.
• Remove all rough-textured, plastic, dowel, and warming perches. Platform perches must be covered in at least 2 layers of fleece held down by binder clips for small perches and clamps for the larger ones. The perch will be larger with the addition of the fleece. Change it as you find droppings on it. Have clean ones cut so you can replace them as needed.
• For birds unaffected by pododermatitis: Perches should be soft. Rope perches are good for general use, and wood perches should be covered with cohesive wrap. (Vetrap is undesirable since it is sticky and holds dirt. Cohesive tape/bandage (white) will make it easier for the owner to notice the dirt and change it more often.
• Provide frequent exposure to partially shaded sunlight. Avoid full sunlight for all birds, but especially for birds with pododermatitis and any illnesses; it will worsen their conditions as the bird will become overheated. Healthy birds should only be exposed to full sun for a very short time; then they should be moved to partial sun and shade.
• Improve cleanliness. Change the fleece several times a week and clean the cages twice a day.
• Birds in a bin must be on soft towels and sheets of fleece cut to the dimensions of the bin. They should stay there until the feet are almost completely healed. When they are returned to their cages, all perches should be wrapped in fleece indefinitely.
• Make necessary environmental changes. Keep the bird room cool, not cold. You don’t want him to chill. The bird’s infection will have raised his body temperature. If he shivers and holds his wings close to his body, he’s too cold.
• Never use a heating pad under the towels or cage, and never use UV lamps on the bird or his cage. UV Lamps should not be used on any bird or his cage. They will burn the skin and cause cataracts. Only ceiling lamps should be used, if at all, and they should only be on 2-3 hours a day.
• Apply a topical antibiotic or antimicrobial cream containing steroids to aid in resolving the condition. (See 7.1 for medications used) These should be used with caution to prevent toxicity. Many topical products are available, such as softening agents for dry, scaly feet, topical antibacterial creams for acute inflammation and swelling, and ointments for granulating wounds.²⁰ (Granulated tissue is new connective tissue and microscopic blood vessels that form on the surfaces of a wound during the healing process [Wikipedia]).
• Utilize prescription medication; it may be needed both for healing and pain and inflammation. This should be discussed with the bird’s avian veterinarian. Provide Celebrex (celecoxib) for pain and inflammation. Avoid Metcam (meloxicam); it is a dog and cat medication and causes digestive issues in birds as well as not being as effective as celecoxib.
• For all levels of disease, the owner must be willing to continue with the treatment at home, possibly for months. He needs to be made aware that some individuals are highly susceptible to recurrences. If the bird does not respond to these changes, or the condition continues to deteriorate, more complex medical treatment will be necessary.²⁰ At that point, you must have a discussion about the bird’s prognosis with the veterinarian. It is of greatest importance to discuss all of the above treatments with your avian veterinarian.

7.4 Additional treatment of the lesions, Grades III to VII

If you do not have an avian vet, contact the author so she can help you find one and follow the rest of the instructions below.

2. Prepare the lesions for treatment at home.

To prepare the lesions for the topical antibiotics, they need to be thoroughly cleaned. Washing the feet with antibacterial soap is sufficient for Grades 1 and 2, but for Grades 3-7, preparation is more comprehensive. One recommendation involves soaking the affected foot/feet in a shallow dish filled with warm water with Epsom Salts added to it. The recommended strength is about one teaspoon of Epsom Salts mixed in with one gallon of clean, warm drinking water. The Epsom Salts will draw out any toxins. Soak for as long as the bird will tolerate it, at least 5 minutes per foot. Do this twice a day. Soaking the feet will soften and remove any scabs; this allows the lesion to drain any pus and debris. Do NOT remove the scab or other material without soaking it first. Allow the material to fall off by itself. Finally, flush the cavity with diluted hydrogen peroxide to clean the wound out and destroy any bacteria. ² (Hydrogen peroxide should be diluted at a 1:10 ratio with water. One part HP, 9 parts water.) (J. Miesle)

3. Transfer the bird to a storage bin of the appropriate size for his species. Prepare the bin by laying down at least 2 soft towels on the bottom. Keep the bird in the bin until the feet are healed. Place a cover on the bin which is partially open for air. A piece of aluminum screening, framed, will work. While the bird’s feet are healing, buy at least 1 yard of very soft fleece. Remove all hard or rough-textured perches from the cage and replace them with natural wood or rope perches. Wrap all perches with overlapping, 1-inch strips of fleece held down by a short piece of twist tie at the end that the bird does not stand on. Make sure perches are the appropriate size for your bird’s species. Cut a piece of fleece (or two smaller pieces) to fit the bin and place them on top of the towels. Make extra pieces to replace the large pieces when soiled. They are washable. Place the bird’s food, water, and toys in the bin. Do not use a heating pad!! The tissue is already hot from being inflamed and/or infected. Have the cage ready for the bird by the time he is ready to go back into it. Do not wait. (J. Miesle)

4. Clean the feet with antibacterial soap, rinse and dry well; apply and massage in the creams. There are two prescription creams that you can get from your avian veterinarian: Gentamicin Sulfate Cream (©Perigo or ©G&W, and ©Neomycin and Polymyxin B Sulfates and Bacitracin Zinc Ophthalmic Ointment, (USP Bausch +Lomb). These may be alternated; you may eventually find one works better than the other. If you cannot get the prescriptions for these, use the OTC medications in the following paragraph. Get the Aloe Vera Gel from Walgreens and mix a very small amount with distilled water to make a medium-thin gel. Obtain VetOmega as discussed on p. 37. Begin to massage the feet with a small amount of triple antibiotic ointment, such as Neosporin followed by the Aloe Vera Gel. Use only this gel or a similar brand. Do this treatment 3 times a day. You can reduce this to 2 times a day as the skin heals. It is available in-store and online from Walgreens. Do not use Aloe Vera plant liquid. It is not sterile and not as effective. (J. Miesle)

5. Once the feet have healed, the bird may be returned to his cage. He will have to be on fleece-covered perches for a long time and possibly permanently, since some birds have a relapse of the condition due to the skin having been compromised. Make sure you remove the fleece strips twice weekly and replace them with clean ones. Check the fleece daily for any signs of fecal material on them. You will eventually be able to change them just once a week. Replace the fleece weekly if there are no open sores, blood or fluid coming from the wounds. Replace the fleece as needed if these exist. Keep a close eye on the condition of the fleece strips. (J. Miesle)

7.4.1. Dressings and bandaging

The severity, type, and path of infection will direct treatment. No matter what, the owner should keep the bird’s feet sanitized and tailor the living environment to both promote healing and to eliminate destructive perches and surfaces.²¹ (Installing rope perches and wrapping all perches with fleece are the best ways to provide soft surfaces). Oral antibiotics and antibiotic ointment will control the infection. Bandaging may be recommended in order to reduce the opportunity for pathogens to enter the wounds. In more severe cases, surgery (including debridement of abscesses) will help to save the feet, and life, of the bird. ² Antibiotics will be essential in resolving infection, and the bird can be kept comfortable with pain and anti-inflammatory medication. ²¹ (Celecoxib [Celebrex] is the best anti-inflammatory and pain medication for birds; do not accept meloxicam as it is not meant for birds and is not as effective as celecoxib. It also has gastrointestinal side effects that celecoxib does not have. (J. Miesle)

Medical therapies include the application of topical agents in order to toughen the plantar skin of the foot. Softening agents are also helpful in cases in which the epithelium has become thin. Antimicrobial and anti-inflammatory creams and ointments and hypertonic footbaths provide infection and inflammation control. ⁵ (Hypertonic refers to a solution with higher osmotic pressure than another solution. If a cell is placed in a hypertonic solution, water will leave the cell, and the cell will shrink [Merriam-Webster.])

Once the wound is clean, apply liberal amounts of antibiotic ointment as prescribed by the veterinarian, and then carefully wrap the foot or feet with gauze; this will keep the cavity clean and the ointment in place and prevent the bird from chewing on it. If the pododermatitis is in the very severe category, a ball bandage may need to be adhered to the foot. The lesion needs to be cleaned and ointments reapplied twice a day until the feet appear healthy.²

Figure 32. A ball bandage is one option for the management of a closed-toe fracture or severe pododermatitis (image courtesy Dr. Ariana Finkelstein, Lafebervet). This type of bandage is frequently used for raptors who are in captivity due to their inability to be released in the wild. They develop pododermatitis from being in enclosures which have concrete floors or hardwood and often, poorly designed perches. (J. Miesle)

6. In severe cases, a hydroactive (combined with water) dressing may be used Hydration sometimes helps to reduce the concentration of toxic substances in the tissue’s dressing and can be used to facilitate healing of the wounds [Merriam –Webster]). Hydrophilic dressings mix easily with water. Moisture-vapor, permeable dressings, or hydrocolloids (a substance that forms a gel when mixed with water) dressings should be applied topically to enhance wound healing for open, granulating wounds or post-operative incisions. Applying a topical antibiotic and bandaging to the feet with sufficient padding to reduce and better distribute pressure on the plantar surfaces is required in many cases. The types of bandaging methods may include simple toe bandages, interdigitating (between the toes) bandages, and ball bandages. Bandaging of affected tissues may go on for several months until the bird responds to the new diet and environmental deficits have been corrected.⁵

Initially, the bandage may require daily changing. The frequency of bandage changes can be reduced as the wound becomes less exudative (producing fluid) especially in inflamed tissue. Once granulation tissue forms at the edge of the ulcers, scabs should be removed by the clinician, and the lesions should be kept clean to facilitate healing.⁵

7.4.2 Therapy for severe lesions

Therapy should include:

• Cleansing and treating the wounds daily with multimodal medications and changing the bandages daily
• Treating the wounds locally by using the antibiotic-impregnated matrix; antibiotic-impregnated beads are implanted into the wound
• Administering systemic antibiotics parenterally (other than by mouth) in the beginning followed by oral dosing
• Prescribing anti-inflammatory analgesics to provide pain relief. NSAIDs (non-steroidal anti-inflammatory drugs; e.g., celecoxib) or synthetic opioids may be used as needed. Celecoxib (Celebrex) is the preferred medication for inflammation and pain in birds. (J. Miesle)
• Testing for systemic infection in more advanced cases of decubital ulceration (bedsores or pressure sores)
• Performing a complete blood count at the discretion of the avian veterinarian.
• Taking swabs regularly from within the abscesses for fungal and bacterial cultures. E. Coli, Staphylococcus, and Candida albicans are commonly isolated pathogens.⁵

7.5 Goals for managing advanced pododermatitis

Advanced bumblefoot is diagnosed by analyzing the necrotizing abscess on the plantar surface of the foot. Depending on the location and chronicity of the abscess, infection may or may not extend to neighboring joints, tendon sheaths, and bones.¹⁰

The goals of advanced bumblefoot treatment are:

• To reduce infection, inflammation, and swelling
• To establish drainage as needed
• To begin antibacterial topical and oral therapy to eliminate underlying pathogens
• To manage the wounds in order to promote rapid healing
• To initiate surgical intervention when needed
• To ensure an adequate diet, and
• To address environmental deficiencies.⁵

Figure 33. Grade VII Pododermatitis in a four-year-old budgerigar with a straight perch in his cage for years (image courtesy of K. Gerbaga Özsemir; used with permission).

This will be accomplished by:

• Correcting any perching and bedding issues
• Adjusting nutrition as needed
• Correcting potential husbandry issues; cleaning and disinfecting the bird’s enclosure in order to eliminate injuries and stresses associated with those
• Correcting the bird’s diet when it is found to be lacking sufficient Vitamin A, (Essential Fatty Acids, and other important nutrients). Vitamin A injections are an option. Recommendations will be made by your avian veterinarian or through research to supplement the diet to increase vitamin A.
• Increasing exercise and adjusting the diet of all ill birds; adjusting the diet of obese birds for weight loss as needed.
• Addressing bacterial infections, whether localized in the wound area or systemic. Cephalexin antibiotics have been used successfully in cases that involve infection that has spread through the body.
• Treating and dressing any wounds or ulcerations that are present to encourage healing
• Using surgical treatments, natural healing products, therapeutic lasers, and even acupuncture as needed. These are determined by the extent to which the pododermatitis has progressed and the recommendation of the avian veterinarian.²¹

See Appendix C, p. 55, for information on laser treatments for pododermatitis.

Figure 34: Grade VII bacterial pododermatitis. This lesion usually develops following pressure necrosis with a subsequent bacterial infection (image courtesy Harrison: Clinical Avian Medicine, 2006).

7.6 Surgical treatment of advanced cases

Advanced cases may warrant surgical debridement (cleaning and cutting away of dead tissue) of fibrotic and exudative material as well as attempts to close the wound with sutures. Debridement should be approached cautiously since hemorrhaging can occur. Surgical excision of the abscess or amputation of a severely traumatized digit or even the foot may be indicated.⁵

Surgery is often necessary to repair damage to the tendons and ligaments. This is a long, slow process, and it may take months before the feet are healed. Even after healing is complete, the foot may still be tender for several weeks. Preventing trauma and maintaining the patient on a soft footing is important to avoid recurrence. (Birds should be kept on soft towels in storage bins during this time and not in their cages.) Waterfowl should be returned to the water as soon as possible to prevent further damage.⁵

Treatment for Grades IV to VII should include drainage, irrigation, and closing of the wound when the infection has been resolved. The prognosis is fair. Treatment for the lesions must be vigorous, and the prognosis is guarded.⁵

8. Consequences of neglecting to provide treatment for pododermatitis

If the bird owner notices the formation of these sores, initiates veterinary treatment, and makes positive changes to the bird’s living environment and diet, the prognosis for healing is good. However, without veterinary attention and environmental improvements, the sores typically turn into painful abscesses, which enable opportunistic pathogens (usually S. aureus) to breach the surface of the thinning skin.²¹

8.1 Pain, arthritis, and infection

The pain from these lesions causes increased weight-bearing on the unaffected foot, forcing the bird to bear its weight disproportionately. As a result, many birds suffer from bilateral pododermatitis. The plantar location of the lesion is constantly under forces of pressure, movement, and contusion (bruising); in addition, the bird’s feet are constantly exposed to contaminants.⁹ These birds are prone to arthritis as well, and this disease only worsens with time.²¹

Celecoxib should be provided for any birds experiencing pain and inflammation for any reason. It is far superior to meloxicam and has fewer side effects.

Figure 35. “Infectious pododermatitis with gross swelling of a foot in a snowy owl. The central scab was removed, and a large amount of liquid pus was present within the foot” (image and text courtesy B. Speer: Current Therapy in Avian Medicine and Surgery).

Figure 36. “After debridement and application of a topical ointment and dressing, an interdigital bandage was applied as well as a custom-fitted silicone shoe” (image and text courtesy B. Speer: Current Therapy in Avian Medicine and Surgery).

8.2 Necrosis, lameness, and decreased quality of life

In due time, the infection encroaches upon joints in the feet and bones in the legs, and surrounding tissues become necrotic. Ulcers may form on the feet, and the bird may become progressively lame.²¹ “Birds beset by advanced and untreated bumblefoot can become so systemically infected that their lives are unsustainable.²¹ If left untreated, the lesions lead to crippling deformities, sepsis, and poor quality of life.⁹ Bacterial infections that begin in the pads of the foot can ultimately lead to a bird’s death. Many surviving birds endure chronic abscesses and the amputation of a leg.²¹ Unless the condition is treated, the infection will eventually eat into the bone and travel to other parts of the body. This is a painful condition that can lead to death.²¹

8.3 Osteomyelitis involvement

If systemic infection and pain can be controlled, the above therapy may be attempted. If the disease state becomes extreme, osteomyelitis occurs, and the prognosis for recovery decreases dramatically. The owner must be forewarned that the therapy will be of a long duration, and the prognosis is poor. The owner and practitioner will need to discuss the ethics of such long, continuous treatment when the degree of disease is so advanced that the bird cannot stand without severe pain. Euthanasia will need to be considered under such circumstances.²⁰

8.4 Limb amputation

If a bird has had a pelvic limb amputation, it is possible that pododermatitis will develop in the opposite leg. These birds benefit greatly from having soft, wide, padded perches and platforms provided for them. (Even better, they should be in bins on soft towels so they don’t have to try and perch.) It is also possible that the wounds will be so severe that they do not respond to medical or surgical therapy, and the second foot or leg will need to be amputated. Euthanasia must be discussed if that occurs.⁶
9. Prevention of pododermatitis

Pododermatitis is easier to prevent than it is to treat. Bumblefoot may be prevented by taking the proper steps to ensure that the bird’s living conditions are correctly designed, it is given a nutritious diet, and its cage and all play areas are kept scrupulously clean. Prevention of pododermatitis involves constant vigilance for early signs of hyperkeratosis, baldness, flaking of the skin of feet and legs, redness or swelling. Early correction of the underlying causes will avert future severe disease.¹⁹

Figure 37. If a bird’s case of pododermatitis is severe, it would be helpful to house him in a “flat,” wide cage. (The term “flat” is used by manufacturers and sellers to distinguish it from the square and tall cages.) These are especially nice for handicapped, aged, or ill birds, not just for those with bumblefoot. A small, fleece-wrapped rope perch or natural perch can be placed in one of the front corners, close to the floor of the cage, once the bird’s condition has improved. Yaheetch® and Chewy® carry these cages, among other companies.

9.1 Choosing the right size cage

Cages should be large enough to accommodate several different types of perches. They should be neither too large nor too small. A cage that is too large will find the bird at the top of the cage, at the highest perch, and staying there most of the time, not taking advantage of the other perches, toys, and food and drink in the rest of the cage. Macaws placed in these huge, double-wide cages rarely move around; they are sedentary for the most part. An appropriately sized cage will benefit the bird by giving him a reason to move about the cage in search of toys and food. If the cage is too small, the bird will not be able to open and spread his wings or move around the cage easily. The idea that the cage should be as large as you can afford is not a good one. The bird feels lost in such a large cage. The ideal size is one that is large enough to be roomy and hold several toys, yet small enough for the bird to feel comfortable and not overwhelmed by the additional unnecessary room in a huge cage (J. Miesle).

Cages should contain horizontal bars for climbing; these will help prevent trauma to the foot pads from vertical bars which need to be gripped to slide down. Care should be taken to make sure that the wire is smooth and contains no sharp places which could puncture or scratch the feet. Even powder-coated cages may contain sharp points which could damage the feet. Any rough places should be found and smoothed over with a file¹⁹ (J. Miesle).

The idea that a cage should be as large as one can afford is not a good one. It should be large enough to be roomy and small enough for the bird to feel comfortable and safe.

J. Miesle

For birds housed in wire enclosures, the walls of the enclosure should be designed with horizontal bars or solid barriers to minimize the tendency for hanging from the wire. Never house birds in galvanized wire structures. Birds will chew on that type of wire and fall ill with metal toxicosis. Selection of proper perch size, shape, and covering for a particular species of bird is very important. ¹⁹ (The reader should discuss this with his avian veterinarian (J. Miesle).

.

Figure 38. Another flat or wide cage. As you can see, soft towels are placed on the top, and food and water dishes can be placed close to the bird’s favorite spot on the cage—in this case, the front left corner. There are several larger pieces of fleece inside the cage on the front right corner for extra softness. And there is a small rope perch on the left front corner, close to the floor of the cage. (In this case, the affected bird never stands on the front left perch, so it is not wrapped in fleece; other birds who visit like to stand on that perch.) The bird with pododermatitis should have any perch in the cage he stands on wrapped in fleece. There are three soft towels on the floor of the cage and toys on the sides and back. The cockatiel whose images were used for Figures 24-27 is on the top of the cage. Make sure the towels come all the way to the edges and sides (image and text courtesy J. Miesle).

Figure 39. Another option, especially for a bird that is elderly or compromised with other health conditions, is to place the bird in a bin on soft towels. This will give him the comfort and security he needs to heal. This bird is blind and cannot fly. This is where he sleeps at night to avoid night frights. The cockatiel in Figure 35 and two other handicapped birds sleep in bins as well. During the day they are out and in wide cages for naptime (image and text courtesy J. Miesle).

The author’s bird in a bin with towels layered for softness. When arthritis becomes very painful, foot sores are present, so placing the bird in a bin on towels is preferable to keeping him in the cage. (An alternative to the bin is a wide cage, as in Figure 35.) There are no bars, multiple towels will protect the feet, and the bird will move about much more easily. Food, water, and toys may be placed in the bin with the bird. As long as the bird’s condition is severe, there should not be any perches in the bin or wide cage.

Do not use a lamp or heating pad for these birds. For birds with bumblefoot, the additional heat from a heating pad or lamp is contraindicated because it will aggravate the condition, making any inflammation, infection, or irritation worse. Heat lamps should never be used on any bird’s cage, attached to the cage or shining into the cage. It will damage the eyes and skin and overheat the bird (J. Miesle).

Figure 40. Grades VI pododermatitis; These sores are necrotic and oozing (image courtesy Brisbane Bird Vet; used with permission). (https://www.facebook.com/ParrotTrustScotland). Note that the skin has pulled away on the right foot, back digit.

Figure 41. Grade VII infectious pododermatitis in a chicken. This bird’s staphylococcus infection is destroying the skin, making it impossible for the skin to be sewn together (image courtesy Farmer’s Weekly).

9.3. Sanitation and substrates

These can be a problem. The wire grid, or any other wire, should never be the surface that any bird stands on, whether it be the floor of the cage or aviary or a platform. It can damage the feet and cause cuts and bruises. Hard or wire flooring that the bird with pododermatitis stands on should be covered with soft towels to protect the feet, facilitate a more comfortable surface on the floor, and speed the healing process. The grids on the bottoms of the cages of a bird with bumblefoot should be covered with two layers of soft towels without anything on top of them, even paper towels.

The grids on the bottoms of non-affected birds’ cages should be covered with either a towel covered with paper towels or just several layers of paper towels in order to prevent cuts, scratches and any other types of damage to the feet. 

Birds should never stand on grids or wire. Any surfaces an affected bird touches should be carefully sanitized and kept clean, and they should always be very soft (J. Miesle).

Proper hygiene is of the utmost importance in preventing bumblefoot.

• Cages and perches need to be cleaned and disinfected daily to avoid contamination from fecal matter and bacterial growth on surfaces and in food.
• Soft foods should be removed within two hours to prevent bacterial growth. Soft or fresh food can be placed on paper towels to make cleanup easier.
• Wipe down any surface that fresh foods have been on as soon as the food has been removed to prevent bacterial growth.
• Seed, food, and water cups should be checked frequently during the day for droppings and debris.
• Food and water cups need to be cleaned daily and replaced with fresh food and water as needed.
• The grates and trays of the cage must be cleaned daily since many birds spend time on the bottom of their cages where they may come in contact with the droppings. Soft towels and/or paper towels on top of them on the grates (or trays if there are no grates) will make clean-up easier.
• All play areas must be kept very clean. Any play surface is a potential source of bacterial and fungal pathogens that could invade the surface of the bird’s feet. T-stands, toys, and anything the bird stands on must be kept scrupulously clean
• Be aware of the possibility of parasites in the cage and/or on the birds. These will make the pododermatitis condition worse.
• Droppings, regurgitation, and soft foods should be cleaned up immediately to prevent consumption, reinfection, and transmission of disease.
• Care must be taken to choose a cleaning product that will not harm the healthy or damaged tissue. All cleaning products need to be dry before allowing the bird to stand on them.³
• White vinegar (2 ¼  cups to a gallon of water) is a good cleaning liquid. Make sure it too is dry before the bird walks on it.

Do not use substrates on the bottom of the cages. These include nut shells, wood chips, grains, corn husks, moss, pine cones, soil, and bedding made for reptiles and small mammals—any type of bedding. These not only provide opportunities for bacterial and fungal spores to grow, but they also put dust into the air that harms the bird’s breathing and makes it impossible for the owner to observe the droppings. Substrates are also harmful to the humans and other pets in the house. Use plain newspaper, and place it where the bird cannot reach it. (J. Miesle)

9.4 Proper nutrition

Nutrition is extremely important. Many affected birds are primarily seed-eaters. Feeding a balanced diet of some seeds (very few sunflower and safflower seeds since they are high in fat and can lead to Fatty Liver Disease), fresh fruits and vegetables, greens, and some human foods is critical. Provide fresh water for drinking daily. Proper nutrition often will prevent or even reverse early bumblefoot in Psittaciformes. The diet should be corrected to promote needed weight loss for obese birds and to increase general nutritional balance, with emphasis on the replacement of Vitamin A precursors.^13,20 Providing Vitamin A injections if needed and foods high in Vitamin A will prevent more damage to the feet. A quality vitamin and mineral supplement is very important. Avi-era (Lafeber) and Missing Link are the best ones. Vitamin and mineral supplements should not be given to birds who are on a pelleted diet. These birds should be weaned off the pellets and onto fresh, natural foods. (J. Miesle)

9.4.1 The harmful effects of excess protein

Excess protein, when stored in the body, promotes the growth of internal bacteria which are excreted through the skin. In areas where there are feathers, those feathers will usually absorb the protein. In bare areas, such as the feet–and in some birds, the face– these bacteria will present themselves as pink, red, and then blue “calluses.” These most often show up on the bottom of the feet; however, they may also appear on the top or on the tips of the toes, above or under the bird’s toenails. It is important to reduce the protein in the bird’s diet to stop the progression of this condition. ² Pellets contain a high amount of protein—another good reason to remove pellets from the diet. (J. Miesle)

9.4.2 The benefits of vitamins, minerals, and supplements

Birds require supplemental vitamins and minerals to aid in the prevention of bumblefoot and improve the immune system to prevent other diseases. Birds require Vitamin A and biotin (a B-complex vitamin) supplementation to ensure healthy skin development.  Deficiencies in these vitamins may result in pododermatitis and focal hyperkeratosis (plantar corns). Bird owners should provide multivitamins, minerals, and essential fatty acids/amino acids supplementation to prevent these diseases.¹² VetOmega will provide the essential fatty acids/amino acids to the bird’s diet. (J. Miesle)

For the affected bird with Grades III to VII, initial injections of Vitamins A and the addition of B-complex vitamins and Vitamin D3 are advised; in addition, oral supplementation of multivitamin/mineral/essential fatty acid/amino acid preparations is recommended.

Your avian veterinarian may also want to provide those injections to birds with Grades I and II pododermatitis. ^1,12,16 ©Avi-era Vitamins and ©Missing Link minerals are excellent choices for vitamin and mineral supplements. Avi-era and Missing Link, and all other vitamins and minerals, should be placed on the food. They can also be mixed with a little water and given via oral syringe. Make small amounts as these need to be discarded at the end of the day. You do not want to give too much to the birds; there are health issues for the bird that ingests too many vitamins and minerals. The paper, Nutritional Requirements of Companion Birds, explains the danger of hyper- and hypovitaminosis. Birds with pododermatitis should be given a small amount each day, alternating, until the bumblefoot has healed, then go to the same schedule as non-afflicted birds. For non-affected birds, a small amount 3 days a week is sufficient. If you provide both Avi-era and Missing Link, alternate them.

Omega 3 and 6 essential fatty acids may be added in the form of ©VetOmega, available through your avian veterinarian or directly from Dr. Scott Echols. This product provides all your birds with the oils it needs for healthy skin and feathers and to protect the internal organs. This link will allow you to order it yourself if your veterinarian does not carry it. Encourage him/her to begin to offer it to his clients. (J. Miesle)
https://www.vetomega.com/?fbclid=IwAR330QUDMPrtHY-rzR6AMrMg- vbPWPf_SmcfmA36qt_q4LpjpM5t0K0wYuAet

9.5 Exercise

Exercise will aid in preventing and healing pododermatitis; the bird who is allowed to fly will spend less time on his feet, and that will give the feet some relief from constantly standing. Make sure everything he stands on is soft! Allow the bird out-of-cage or out-of-bin time frequently throughout the day so that he can fly and strengthen his legs; this will take the pressure off the feet. Exercise will also aid in lowering the obese bird’s weight.¹¹ If the bird does not fly, allow him to walk on the floor, but only if the floor has soft coverings like carpeting, towels, blankets, or rugs. Walking on sofas or beds is another good place for him to exercise. Many of these birds have some arthritis, and exercise will benefit them. Many birds with pododermatitis have developed arthritis before the sores on the feet are even discovered (J. Miesle).
Conclusion

Pododermatitis is a disease that is easily preventable with the proper environment and nutrition. In the early grades, it is somewhat easy to control, and reversing the disease process is possible. In later grades, however, it becomes increasingly more problematic to treat and can, eventually, lead to permanent crippling and even death; therefore, the bird owner is advised to be continually vigilant, observing the condition of the bird’s feet on a daily basis. At the first sign of a lesion or bruise on the foot, the diligent owner should take the bird to the avian veterinarian for diagnosis and treatment. When treatment and changes in diet and husbandry are initiated early in the disease, the chance of recovery is very good. The owner should change or cover the perches immediately so the disease does not become progressively worse. It is essential that the owner be attentive in caring for his birds.

References:

1. Axelson D. Avian Dermatology. In: Practical Avian Medicine: The Compendium Collection. Ed: Heidi Hoefer. Veterinary Learning Systems, 1997. p. 200
2 Beauty of Birds. Bumblefoot. https://www.beautyofbirds.com/bumblefoot.html
3. Clubb S, Flammer, K. The Avian Flock. In: Avian Medicine: Principles and Application SPIX Pub., Inc. p. 50, 56-58
4. Cooper J.E., Harrison G. Dermatology. In: Avian Medicine, Principles and Application. SPIX Pub., Inc. P. 632
5. Degernes L. Trauma Medicine. In: Avian Medicine, Principles and Application. SPIX Pub., Inc. 2006. p. 425, 426
6. Doneley R, Harrison G, Lightfoot T. Maximizing Information from the Physical Examination. In: Clinical Avian Medicine, Spix Pub., Inc. p. 190, 404
7. Doneley R., Smith B., Gibson J. Use of a Vascular Access Port for Antibiotic Administration in the Treatment of Pododermatitis in a Chicken. J Avian Med Surg 29 (2) 130-135, 2015.
8. Dumonceaux G., Harrison G. Toxins. In: Avian Medicine, Principles and Application. SPIX Pub., Inc. 2006. P. 1047, 1048
9. Ford S., Chitty J., Jones M. Raptor Medicine Master Class. Proc Assn Avian Vet 2008 p. 173-190
10. Gerlock H. Bacteria. Avian Medicine: Principles and Applications. SPIX Pub., Inc. p. 967
11. Helmer P., Redig P. Surgical Resolution of Orthopedic Disorders. In: Clinical Avian Medicine. SPIX Pub., Inc. p. 771, 772
12. Koski M. Dermatologic Diseases in Psittacine Birds. In: Seminars in Avian and Exotic Pet Medicine, Vol. 11, No. 3 (July), 2002. p. 120
13. McDonald D, Harrison G. Nutritional Considerations. In: Clinical Avian Medicine. SPIX Pub., Inc., 2006 p. 117
14. Miesle J. The Effects of Tobacco Use on Avian Species. In: Facebook group The Science of Avian Health File, Academia.edu, IVIS website. 2017
15. Olsen J. Anseriformes. In: Avian Medicine, Principles and Application. SPIX Pub., Inc. 2006. p. 923
16. Perpinon D. Obesity in Parrots. The Veterinary expert.  http://www.theveterinaryexpert.com/parrots/obesity-in-parrots/
17. Ritzman T. Therapeutic laser Treatment for Exotic Animal Patients, Round Table Discussion. AAV J Avian Med Surg 29 (1):69-73, 2015
18. Samour J. Management of Raptors. In: Clinical Avian Medicine. SPIX Pub., Inc., 2006, p. 923
19. Sander S, et al. Advancement Flap as a Novel Treatment for a Pododermatitis Lesion in a Red- tailed Hawk. J Avian Med Surg 27(4): 294-300, 2013.
20. Schmidt R, Lightfoot T. Integument. In: Clinical Avian Medicine. SPIX Pub., Inc., 2006, p. 403, 404
21. Turner C. Bumblefoot in Birds. Wagwalking. https://wagwalking.com/bird/condition/bumblefoot
22. Van Sant F. The Integument: The Largest Organ System of Birds. Proc Assn Avian Vet 2014

Appendix A: Treatment of raptors, poultry, and waterfowl

In captive raptors, bumblefoot is a common medical condition, even though it is never seen in the wild. Some raptor species appear to be more susceptible to this condition than others; falcons present with this frequently, but it is rarely seen in hawks. It is a result of poor nutrition, obesity, inadequate perches, lack of exercise, poor blood circulation to the foot, and cardiovascular changes at the end of the hunting season.¹⁸

Penetrating wounds or bruising of the feet may be predisposing factors in raptors and waterfowl. Grades I to III lesions may not be discovered in raptors; most are not seen until they have more severe lesions.⁴

In captivity, raptors are prone to bruising and abrasions on the plantar surface of the feet from jumping from a hard perch onto another hard surface, such as a stone floor and from hanging from cage wire by their feet, or being forced to stand on hard perches or cement. Any soft tissue or orthopedic injury involving one leg or foot may cause excessive weight-bearing and secondary pododermatitis on the contralateral foot (the foot on the other side.) ⁵

Overgrown talons cause improper weight distribution on the plantar surface of the foot, especially in falcons, or self-inflicted puncture wounds of the metatarsal pad. Other traumatic injuries to the foot which can lead to bumblefoot include bite wounds from prey, punctures from thorns or quills, and trap injuries.⁵

From Dr. Bart Huber, Animal Medical Center of Corona, California

https://www.facebook.com/amcofcorona/

Radiographs of a chicken with severe pododermatitis brought on by a fracture which caused the bird to stand in a way which put undue pressure on that foot.

“Once the bone has been invaded, chances of a cure are almost zero. Now, there is a newer product, Kerrier beads – Kerrier.com – where we buy this sterile kit and can make antibiotic impregnated Plaster of Paris beads that we implant into the affected foot (or where the patient has a bone infection.) The issue in the past is that there was not sufficient circulation to get enough antibiotics via the blood stream to the lesion. With these, the lesions are packed with antibiotics, increasing the healing rate. It does not get rid of the arthritis from the damaged bone, but it does give us hope. Sadly, most of these back yard birds end up getting euthanized.”

Figure 42-49. Pododermatitis caused by a fracture in the leg. This is an example of the disease being caused by an injury above the foot, not on the foot directly. Dr. Bart Huber has kindly allowed us to use these images.

The author expresses her gratitude to Dr. Huber for his generous permission to use these images.

A bird’s inactivity in an enclosure, limiting its ability to fly, is a contributing factor. In a study by P.T. Redig (Ford: Raptor Medicine Master Class), raptors that were housed outdoors and were able to exercise did not develop bumblefoot, regardless of their perching surfaces. The group that was maintained indoors on the same diet developed bumblefoot irrespective of the perching material.⁵

For large birds and raptors housed in wire enclosures, the walls of the enclosure should be designed with horizontal bars or solid barriers to minimize the tendency for hanging from the wire. The selection of proper perch size, shape, and covering for a particular species of bird is very important. Perches wrapped with hemp rope or covered with Astroturf work well for most raptors. Falcons do best on flat shelves or block perches covered with short Astroturf or cocoa mats. Strict sanitation of the facilities and feet is important to minimize bacterial infections. Liquid bandage products work well for minor skin cracks or torn talon sheaths in raptors.⁵ The feet should be massaged with a healing product, such as coconut oil or Aloe Vera gel (see 7.1)  (J. Miesle).

Figure 50. Red-tailed hawk at Wild Care in Eastham, MA. “One talon had to be removed due to a serious infection in the feet. He is on ball bandages. The caregivers are optimistic about his ability to be returned to the wild” (image courtesy Cape Cod Capecast). 

In most cases, treatment involves the surgical removal of scabs and adjacent necrotic and purulent (pus-filled) tissue, followed by suturing to achieve healing by first intention (the wound is held together by a blood clot or sutures). Sometimes antibiotic-impregnated beads are placed within the wound cavity to improve the rate of healing. If the opening is larger, sutures are used along with hydrocolloid dressings to promote healing.¹⁸

Figure 51. Grade VII “Bumblefoot infection has spread across both of this bird’s feet. The areas affected look blackened” (image courtesy The Veterinary Expert; used with permission).

Figure 52. Grade VI “A discrete bumblefoot lesion, showing typical positioning at the weight-bearing position on the base of the foot.” (image courtesy The Veterinary Expert; used with permission). (Discrete refers to a single lesion that is localized as opposed to a diffuse lesion in which there are multiple lesions present)

Figure 53. “Chickens cope incredibly well with legs bandaged! This bird has had surgery for bumblefoot. The bandages cover the surgical site as well as allowing pressure relief to the feet whilst the area in question heals” (image courtesy The Veterinary Expert; used with permission).

“Captive waterfowl are also at increased risk for developing this condition because of their heavy-bodied nature and the amount of time they spend standing on rough, hard surfaces around pools or pens. Waterfowl may suffer penetrating wounds and bruises on the feet which lead to pododermatitis.”¹⁵ Caring for waterfowl frequently involves changing the dimension, shape, and surface of the enclosure, adding adequate swimming areas, and keeping everything very clean.²⁰

Figure 54. “A silver gull with a tibiotarsus fracture on its right leg (Larus michahellis) His solid left foot, burdened with more weight than normal, resulted in pododermatitis” (image courtesy Kübra Gerbaga Özsemir).

“Pododermatitis is common in poultry. VAPs (Vascular Access Ports) are more commonly used in mammalian patients but are sometimes used to treat avian patients requiring long-term intravenous therapy or serial blood collection. Vascular Access Ports offer the advantages of ease of access, reduced trauma and handling of the patient, and the accurate delivery of large volumes of tissue-irritating drugs. Although this technique is used for mammals, it is still considered a novel treatment for avian species.” ⁷

Figure 55. Grade VII bumblefoot foot in a buzzard (Buteo buteo). This bird had been shot and had developed severe arthritis of the tibiotarsal joint of the contralateral limb. The wounds oozed blood as well. The bird was emaciated and had a heavy worm burden. Excessive weight bearing on the healthy leg, coupled with malnutrition, is likely to have resulted in the lesions depicted (image courtesy World Wide Wounds).

Figure 56. Grade VII pododermatitis in a chicken (image courtesy Monica Talbett; used with permission).

Figure 57. Grade VI pododermatitis. The chicken’s foot before surgery (image courtesy of The Chicken Chick).

Figure 58. The chicken’s foot four months after surgery (image courtesy The Chicken Chick).

Appendix B: Food choices for affected birds J. Miesle

Vitamins should always be given to birds unless they are on a pelleted diet. These birds should be taken off pellets and put on a more natural diet. Avi-era and Missing Link are good choices for vitamins. They can be purchased online or at some bird shops. If only one is fed, feed 3 times a week on food, not in water. If both are fed, alternate.

These foods are appropriate for other small birds like budgies, lovebirds, and medium and large birds as well. It is recommended to purchase everything separately and make your own mix. Don’t buy from big box stores or dog/cat pet stores. These stores may have had the food sitting in warehouses for months or even years. Even if they sell birds, they buy from the big box stores. With bird-only stores, they buy quality, and you don’t run the risk of having contaminants like mold, animal droppings, and saliva in the food that you would with food from other sources.

Don’t hesitate to eat with your bird. Many birds will start eating good foods if fed at the table with the owner and/or other birds. It’s a great bonding time.

Cereals:

• Sugar-free cereals, like Wheat, Rice, and Corn Chex; some like it moistened with a little rice, almond, or other non-dairy milk.
• Flakes, like Wheaties, Total, and cornflakes; Cheerios and other low-sugar cereals are good. Some may have small amounts of sugar, which is OK, but if sugar is among the first 3 ingredients, the food will have too much sugar in it and should be avoided.
• Flax seed—available at grocery stores, only for small birds.
• Low-sugar granola, e.g., Quaker Puffed Granola, Blueberry-Vanilla Flavor. It has small freeze dried blueberries in it.

Other foods:

• Nutriberries and Avi-cakes; these are labeled as treats, but they are not. They are nutritious foods. They come in three sizes.
• Kaytee parakeet Forti-diet Honey Treat Bars for small to medium size birds. Break them up and give a small amount per day. Don’t just put the whole thing in the cage. Some of these birds will eat nothing else if allowed. Parakeet bars do not have sunflower or safflower in them, but the larger sizes do. https://www.chewy.com/kaytee-forti-diet-pro- health-honey/dp/122876.
  Available at Chewy, Amazon, and Petco, among others.

Seeds

• Parakeet seed instead of cockatiel or other seeds for mid-sized birds. They are the same, except that cockatiel includes a lot of sunflower and safflower, both bad for the liver. Read the ingredients on everything you buy.
• Oat groats: Some grocery stores carry it. Great Companions, Amazon, and Shiloh Farms do. Shiloh farms has good quality and price. Whole Foods or other similar stores may carry it. Amazon carries some good-quality groats. Do not buy anything that is cheap; it isn’t worth it.
• Red and white/yellow proso millet: These are small seeds, so only small birds would eat them.
• Nuts are good for larger birds, but only feed tree nuts. Avoid peanuts and all peanut products. They usually contain mold spores. Those small black spots on the shell and nut are mold spores, and mold can be in the peanut products at the store.

White/yellow proso millet is available at some grocery stores or over the internet. Morning Bird carries red and white proso millet. Red is a particular favorite of cockatiels.

https://morningbirdproducts.com/collections/bird- seed, https://www.morningbirdproducts.com/products/morning-bird-red-proso- millet?_pos=1&_sid=937075e06&_ss=r
https://www.shilohfarmsmarket.com/ https://www.shilohfarms.com/

NEVER BUY SEEDS FROM NON-AVIAN PET SHOPS OR BIG-BOX STORES. THEIR SEEDS ARE STORED FOR MONTHS OR LONGER AND MAY BE CONTAMINATED WITH ANIMAL DROPPINGS OR OTHER DIRT, AND WILD ANIMALS MAY HAVE EATEN FROM THE PACKAGES.

Millet sprays:

• Amazon, Nemeth Farms, has two bluebirds on top of millet. From “Bird Dog” Excellent quality. Available in 1 lb. bags, 5 lb. boxes, and 25 lb. boxes. It’s quite expensive, but you get what you pay for. There is very little waste, and the sprays are full and fresh. It looks like this:

https://www.amazon.com/Nemeth-Farms-Parakeet-Natural- Healthy/dp/B001LK91O4/ref=sr_1_2?keywords=spray+millet+for+birds&qid=1567312878&s=ga teway&sr=8-2
https://www.amazon.com/Nemeth-Farms-Parakeet-Natural- Healthy/dp/B0068RFAFO/ref=sr_1_1?dchild=1&keywords=nemeth+farm+millet&qid=16088633 59&s=pet-supplies&sr=1-1

These websites have changed to offering the millet in 1-pound bags, not the 5 and 25 lb. boxes. Another distributor in Amazon carried it. and found the 5 and 25 lb. boxes. Here is the link: https://www.amazon.com/Pesticide-Nemeth-Supplement-Cockatiels-Finches- 5lbs/dp/B001LK91O4/ref=sxts_rp_s_sp_1_0?content-id=amzn1.sym.497ddbaf-dbdc-4a61-b204- 33f5c59012b2%3Aamzn1.sym.497ddbaf-dbdc-4a61-b204- 33f5c59012b2&crid=2UGGL33HCZTNM&cv_ct_cx=millet%2Bspray%2Bfor%2Bbirds&keywords=millet% 2Bspray%2Bfor%2Bbirds&pd_rd_i=B001LK91O4&pd_rd_r=143c599f-3eb0-442a-a40b- 8c6cb500d950&pd_rd_w=xCxPs&pd_rd_wg=9ywgo&pf_rd_p=497ddbaf-dbdc-4a61-b204- 33f5c59012b2&pf_rd_r=D8V565J9WBVWKQZSVSQK&qid=1669429901&sprefix=millet%2Bspray%2B% 2Caps%2C73&sr=1-1-5985efba-8948-4f09-9122-d605505c9d1e&th=1

• Buckwheat seeds and groats. Meijers sometimes carries it, best price at Shiloh farms. https://www.shilohfarms.com/buckwheat-groats-organic/
• Zupreem fruit-flavored pellets for cockatiels and medium-sized birds, Chewy carries them; a few a day if they like them. It’s not for a nutritional benefit; simply if they like them.
• Kaytee Fruit and Veggie mix and Fruit Mix for Parakeets, and other parakeet mixes. Chewy, Petco, or Amazon.
• NO GRIT, EVER, FOR PSITTACINES BIRDS! Only birds that eat their seeds whole use grit; Psittacines (birds in the parrot family) do not. They shell their seeds. Birds like canaries, doves, and pigeons only need a very small amount; more should only be added when that amount is gone. Otherwise, they can develop crop impaction.

Human foods:

• Rice, pasta, mashed potatoes, sweet potatoes, couscous, scrambled egg, applesauce (a real favorite, and a way to get fruit into them). It’s also a good way to train them to take food and medications from an oral syringe. Human foods are OK as long as they are not fatty, fried, or breaded. For more protein, baked chicken breast, ground beef, roast beef are good, and from the deli, roast beef and chicken slices and low sodium ham are good. Usually, only the larger birds eat meat, but some smaller ones will try it. Some of the author’s cockatiels eat meat.
• Tomato sauce (plain or mildly spicy), for spaghetti or on ground beef, small amounts
• Peas, corn, and other vegetables such as fresh green beans, asparagus, cauliflower, and broccoli, all lightly steamed or cooked are good. Cauliflower and broccoli can be given raw but there’s more nutritional value in them steamed. Even though the “raw diet” is popular right now, it is not always good for them. Most vegetables need to be cooked to release their nutritional value, and some birds have digestive issues when fed raw vegetables.
• No raw sweet potatoes! Serve only the fleshy meat inside; no seeds, stringy parts by the peel, or the peel itself.
• Never feed yams. Don’t confuse yams with sweet potatoes. These are toxic to birds. (This information from T. J. Miesle, Food Chemist.)
• Whole Foods, and similar stores, have different seeds and grains. Some they like; some they don’t. Try different foods with them. They love couscous, and other grains may be found in these types of stores.
• Whole grain bread. Oat-nut is a favorite. Quality white bread is good in small amounts-many like their bread toasted.
• Soft cheese, like American cheese, occasionally. No other types since some have mold on them (like blue cheese).
• No dairy products, or rarely. I know many people like to give yogurt, but yogurt is dairy; if you give it, give small amounts and infrequently. They can’t digest lactobacillus.

Organic: “Organic” is not really different from regular food. Every state has different rules and regulations about what farmers can and can’t use on their crops. And many of the foods we get are imported, where there are no regulations. Finally, once the food leaves the farm, there is no control at all as to what happens to it. It is handled by many middlemen between the farm and your table. (T.J. Miesle)
Appendix C: The use of lasers in the treatment of pododermatitis

In 2014, ten veterinarians met during an Association of Avian Veterinarians conference to discuss the use of therapeutic lasers in treating avian and other exotics patients. Lasers are being used in veterinary medicine with positive clinical results, and low-power therapeutic lasers have proven effective for the treatment of wounds, reduction of inflammation, and modulation of pain. ¹⁷ The results of the discussion are as follows:

• All of the attending clinicians had used therapeutic laser treatment with birds and other exotics in their clinical work.
• These uses included:
  1. Healing wounds that have resisted previous therapies
  2. Painful conditions
  3. Wounds and skin infections
  4. Postsurgical incision treatment
  5. Osteoarthritis
  6. Pododermatitis
  7. Any inflammatory condition or traumatic lesion.⁷

When asked about the kind of response they observed with therapeutic laser treatment compared to routine care, the practitioners responded positively:

Their responses included:

• Improvement in cases of pododermatitis; some with dramatic improvement
• Faster healing time
• Decrease in the severity of wound cases
• Improved mobility in orthopedic cases
• Accelerated healing time, particularly in the dermal wound healing of the foot.
• Improvement in a chicken with bumblefoot, both in improved weight-bearing and decreased inflammation after just one treatment.
• Reduction of the bacterial colony in a wound
• Increased tolerance of the treatment; some are even able to relax a little during the treatment.⁷

Figure 59. “A cockatiel, with a chronic, long-term self-mutilation site, responded to his one session two weeks ago and received another one just in case. We had performed a complete set of appropriate tests on him over the last two years, including bloodwork and radiographs, as well as a removal and biopsy of the affected skin to rule out damaged nerves” (image courtesy Vanessa Rolfe, The Bird and Exotic Hospital; used with permission).

A discussion of the advantages and disadvantages of therapeutic laser treatment in avian patients yielded the following results:

• The benefits:
  1. An increase in the level of healing for pododermatitis patients
  2. An adjunct to medical therapy alone
  3. Improved speed of treatment and response time, leading to less stress on the patient and better recovery and survivability of the patient.¹⁷
• The drawbacks:
  1. Difficulty in objectively determining the effectiveness or success of the laser treatments
  2. The lack of specific protocols for the use of the laser
  3. The large amount of misinformation or disinformation being spread, which serves to confuse the clinician
  4. The lack of scientific studies in the literature about laser use. Those that are published sometimes have limited access, so clinicians may not have been able to read them and thus may not feel comfortable with their use.¹⁷

All concluded that the advantages significantly outweighed the disadvantages. Although lasers have been used for some time by veterinarians, they have not been used as long by avian and exotic veterinarians. All agreed that the differences between avian tissue and mammalian tissue warranted a more careful study of the techniques involved and results gleaned from such use, and far more care needs to be taken when applying laser treatment to birds.¹⁷

Introduction

When people think of bacteria, they consider them just disease-causing organisms, but the vast majority of bacteria don’t cause disease. Rather, they play important roles in the environment and health of all living things, including humans and birds. They contribute to food and oxygen production. Neither plants nor animals could survive without bacteria.

Bacterial pathogens have existed for millennia. In past centuries, many remained in the hilly, forested lands around the world. In the past two centuries, however, as farm land was being developed and forests were torn down to make way for cities and buildings, many of the bacterial and viral pathogens lost their secret homes and went in search of new hosts to inhabit.

As long as these bacteria remained in the hills, forests, waterways, and farmland, they had no need to spread out. Many of the bacterial diseases that once were thought to be long gone and no longer a threat are recurring and persisting. Most occurred in Asia and Africa, where deforestation is rampant. Animals are also subject to illness from these pathogens. Before we delve into the bacteria that are most commonly found in birds, we will explore those frequently used antibiotics administered to avian species since there are references to them in the paper.

Part 1 The Role of Antibiotics in Avian Health

1.1 The Origin of Antibiotics

Bacteria are single-celled microorganisms that appear in many different metabolic types, geometric shapes, and environmental habitats. Some are beneficial for people and animals, and some are not. They can only be seen microscopically, and most have yet to be categorized.⁵

1.1.1 Sir Alexander Fleming and Penicillin

Humans have been using antibiotics for themselves and animals for decades, but these drugs have not been used for birds for nearly that long. Physicians and physicists have known since 1874 that “certain cultures of the mold, Penicillium glaucum, inhibited bacterial

contamination,” ⁶ but it wasn’t until 1928, when Sir Alexander Fleming identified what is known today as penicillin, that it was able to be used commercially. He found that molecules which were produced by certain molds killed or stopped the growth of specific bacteria. Fleming was doing research on a “culture of disease-causing bacteria when he noticed the spores of a green mold, Penicillium chrysogenum, in one of his culture plates.” ⁶ Fleming theorized that the mold must secrete an antibacterial substance, and he named it, “penicillin.” His work won him the Nobel Prize. It was first used during World War II, and soon after the war it was made available to the general public. Understanding the vast world of antibiotics and anti-infectives is no easy task. ^{13, 6}

Image 1. Alexander Fleming, the discoverer of penicillin (image courtesy Biology Corner). https://www.biologycorner.com/worksheets/articles/alexander_fleming.html

Image 2. This mold, identified as Penicillium notatum, had inhibited the growth of a colony of Staphylococcal bacteria in the Petri dish (image courtesy YS journal.com via en.wikipedia.org.)

1.1.2 The Light Microscope

The microscope is the most important tool the avian veterinarian has for discovering the pathogens that are found in birds. It enables him to see the bacteria, fungi, protozoa, parasites, and viral inclusion bodies, many times without or before staining.

The light microscope employs visible light to small samples and is probably the most well-known and well-used research tool in biology. It is used to view samples with the available room light or with a light affixed to the microscope. The smallest objects that are considered to be living are bacteria, and even those may be observed and cell shape recognized at a mere 100x magnification. It is also called “Bright Field Microscopy.” ¹⁴

In optical or light microscopy, visible light is transmitted through or reflected from the sample through a single or multiple lenses to allow for magnification of the sample. This image may be seen directly by the eye, viewed on a photographic plate, or captured as a digital image. ¹⁴

Image 3. A stereo microscope

1.2 Classification of Antibacterial Medications and Their Functions

1.2.1 Antibiotic Classifications

Antimicrobials are medications that kill or stop the action of a bacterial pathogen. Antimicrobials are classified according to their function. Antibiotics are one class of antimicrobials; they fight against bacteria. Another class is anti-mycotic; these will stop fungal diseases. Anti-viral attack viruses, and anti-protozoal drugs fight protozoal diseases. Most antibiotics fall into their individual antibiotic classes. An antibiotic class is a grouping of different drugs that have similar chemical and pharmacologic properties. “Their chemical structures may look comparable, and drugs within the same class may kill the same or related bacteria.” ¹

1.2.2 Broad- and Narrow-spectrum Antibiotics

Not all antibiotics work against all types of bacteria. Narrow-spectrum antibiotics are only effective against a limited range of bacteria; for example, penicillin G is very effective at killing gram-positive bacteria, but not very effective against gram-negative bacteria. Broad-spectrum antibiotics are effective against a wide range of bacteria. ¹⁶

What causes an antibiotic to have a narrow spectrum of antimicrobial activity? “Often, it has to do with the ability of the antibiotic to penetrate inside of the bacterium. Gram-positive bacteria have a relatively loose outer wall that many antibiotics can diffuse through. However, gram-negative bacteria have a complex outer layer that prevents the passage of many larger or fat-soluble molecules.” ¹⁶

Another reason that antibiotics can have a narrow spectrum of activity can be their target molecules. If an antibiotic targets a molecule that is not in the bacterium, it won’t be effective against that bacterium. For example, isoniazid specifically targets mycobacteria, the bacterium that causes tuberculosis. It’s specific because it prevents the synthesis of mycolic acids, which are found in the cell walls of mycobacteria, but not most other types of bacteria. ¹⁶

If the patient is treated with an antibiotic that has a narrow spectrum of activity, the ‘good’ bacteria that normally live inside the body won’t all get destroyed along with the pathogen that caused the infection. However, it is not always clear which microbe is causing the illness; therefore, the patient will be started on a broad-spectrum antibiotic so that the medication can work quickly and the patient can survive until the specific bacterium is determined and the more appropriate antibiotic is prescribed. ¹⁶

1.3 Bactericidal and Bacteriostatic Antibiotics

Antibiotics are generally divided into two groups based on their method of action. They either kill bacteria or prevent them from growing. They are prescribed when there is an infection that the body’s immune system is unable to deal with. Antibiotics that kill bacteria directly are called “bactericidal,” which means “kill bacteria,” and those that stop bacteria from growing are called “bacteriostatic,” or “staying stable.”. ¹⁶

Image 4. The difference between bactericidal and bacteriostatic medications’ effect on bacteria in a laboratory setting (image courtesy Slide Share). https://www.slideshare.net/kyawsanlin25/terminologies-on-anti-infective-agents

1.3.1 The Mechanism of Bactericidal Antibiotics

The different antibiotics have different mechanisms. For example, “the antibiotic polymyxin B injures the plasma membrane of bacteria, allowing their contents to leak out of the cell wall. Under normal circumstances, bacteria and other cells have to keep a perfect balance of ions on both sides of the plasma membrane because of osmosis. Polymyxin B disrupts this balance and also lets other important molecules, like DNA and RNA, leak out, and so the bacterium is destroyed.” ⁷ Other bactericidal antibiotics include vancomycin, metronidazole, aminoglycosides, fluoroquinolones, penicillin, and cephalosporins. ¹⁶ The minimum concentration of a drug that is needed to kill a certain strain of bacteria is called the “minimum bactericidal concentration” or MBC. ¹⁶

1.3.2 The Mechanism of Bacteriostatic Antibiotics

In contrast to bactericidal antibiotics, bacteriostatic antibiotics inhibit the growth of the bacteria. The bacteria don’t die, but neither can they grow or replicate. Unlike the bactericidal agents, when bacteriostatic agents are used, microorganisms remain viable, and their numbers remain the same. Bacteria normally divide really quickly in the body, and their numbers can quickly get out of control. Bacteriostatic antibiotics stop them from growing and dividing, so the host’s immune system will then be able to take over and destroy the harmful bacteria. ¹⁶

Bacteriostatic agents are used to limit the growth and reproduction of microorganisms by interfering with their protein production, DNA replication, or other aspects of bacterial cellular metabolism. Unlike the bactericidal agents, the bacteriostatic agents must work together with the immune system to inhibit the microorganism’s activities. According to drug concentration, the activity may vary. For example, if high concentrations of bacteriostatic agents are used, they may kill the bacteria, whereas low concentration of bactericidal agents may simply inhibit their growth. Tetracycline, sulfonamides, spectinomycin, trimethoprim, chloramphenicol, macrolides and lincosamides are some examples of bacteriostatic agents. Minimum concentration of a drug that is needed to inhibit the growth of a certain strain of bacteria is known as “minimum inhibitory concentration” or MIC. ¹⁶

Tetracycline is an example of a bacteriostatic antibiotic. It inhibits the bacterial ribosomes so that no new proteins can be made. This doesn’t kill the bacteria; they already have the proteins they need to survive for a while. However, they can’t replicate because they would need to make many new proteins in order to make a whole new bacterial cell. Other bacteriostatic antibiotics include chloramphenicol, trimethoprim, clindamycin, sulfamethoxazole, and erythromycin. ¹⁶

1.4 Determining Factors When Choosing an Antibiotic

 In some cases, there may be multiple bacteria present. One antibiotic might kill one strain but only inhibit the growth of another. It is for this reason that the veterinarian may choose to use two different antibiotics. The practitioner needs to know all aspects of the bacteria and the antibiotics he wishes to use before making his choices. He may choose one or both types when treating an infection. His choice depends on:

• The type of infection
• Growth conditions of the microorganisms
• Bacterial density
• Test duration, and the
• Reduction rate of the bacteria.⁴⁸

In most cases of antibiotic use, a doctor must choose an antibiotic based on the most likely cause of the infection. For instance, if the bird has a skin infection, the doctor needs to know which antibiotic to prescribe for skin infections, and he will prescribe the best antibiotic for that type of bacteria. ^{8, 48}

1.4.1 Testing to Determine Antibiotic Sensitivity

Laboratory tests may be required for the veterinarian to choose the proper medication. Gram’s stains can be used to identify bacteria under the microscope; these will also tell him which bacteria are present and provide information he needs to choose the proper antibiotic. Certain bacterial species will take a stain, and others will not. Those that don’t will be examined directly under the microscope. Many times, the veterinarian will do both—direct and stained microscopic analysis. ⁴⁸

Image 5. Bacteriology plate showing the antibiotic sensitivity. “The best antibiotic to use is the one which leaves a clear ring around the antibiotic disk. This is how we choose which drug will work best in a difficult situation” (image courtesy Michael J. Cannon) ¹³

The veterinarian may need to do a culture on a bacterial sample which is allowed to grow in a laboratory. The results may take a few days to come back from the lab. The way bacteria grow or what they look like when they grow will help to identify the bacterial species. Cultures may also be tested to determine antibiotic sensitivities. “A sensitivity list is the roster of antibiotics that kills a particular bacterial type.” ⁴⁸ This list will confirm that the correct antibiotic is being dispensed. Treatment is based on the location of the infection and the results of the culture-and-sensitivity testing. ⁴⁸

1.4.2 Other Considerations When Choosing an Antibiotic

The practitioner must also consider the species he’s dealing with. Songbirds, canaries and finches, poultry, and psittacines all belong to different taxonomic orders. They react differently to medications, and this needs to be taken into consideration by the veterinarian. The practitioner must consider other factors when choosing an antibiotic: medication costs, dosing schedule, and common side effects are often taken into account. He must also consider how the bird reacts to a specific antibiotic; if there is a negative reaction, he will have to change to a different antibiotic. In some aviaries or households with multiple birds, and if the infection is transmittable to other birds, all the birds may need to receive the antibiotic. If it is a zoonotic disease (transmittable to humans), the clinician will advise the owner to see his own physician. ⁴⁸

A very important question the veterinarian must ask the client concerns the owner’s comfort level with giving the bird the medication. Some people are really confident with syringing medications into the bird or giving injections, and others simply can’t bring themselves to do it. For those who feel they are unable to give their bird the needed medication, the veterinarian might choose to give the bird a long-acting injection in the office if the antibiotic comes in an injectable form. This way, the owner might not have to administer medication himself. Sometimes the veterinarian will begin with a fast-acting injection, and the client will need to continue the treatment with oral medication at home. ⁴⁸

1.4.3 Incorrect Antibiotic Usage in Birds

Even though antibiotics are used quite commonly in aviculture, many owners are confused about how they work and how they are used. If they are not used correctly, or the bird develops a resistance to it, the drug may not work at all. This is often a major problem, since if either is the case, the drug may be of no use to the patient. ¹³

The purpose of using an antibiotic is for the bird to develop “strong, adequate levels of the drug in the bloodstream.” ¹³ The blood’s job is to carry the antibiotic to the infected area of the body. If the dose of the antibiotic is too low, or if it is not given frequently enough, it will fail to work. In addition, if the antibiotic is not used correctly, the bird may develop a resistance to the drug, and other birds in the home or aviary may be at risk of contracting the disease. ¹³

Due to the misuse and overuse of antibiotics, some people have a negative opinion about antibiotics, both for themselves and their pets. This negativity is unfounded; antibiotics are extremely valuable medications. Antibiotics have changed medicine for the better, having been instrumental in curing such infectious diseases as pneumonia and tuberculosis. When used correctly, they are a vital tool for the practitioner. ^6.

1.4.4 Correct Use of Antibiotics in Birds

The antibiotic’s purpose is to kill bacteria; however, they do not all work the same way. Some kill gram-positive bacteria, while others kill gram-negative bacteria. Most gram-negative bacteria are harmful, and most gram-positive bacteria are beneficial and are normally in the body; however, there are some very dangerous gram-positive bacteria out there. Since penicillin has come on the market, there have been many new classes of antibiotics created to deal with the different strains of bacteria. For example, fluoroquinolones such as enrofloxacin (Baytril) are used extensively by avian veterinarians. Giving the wrong antibiotic for a specific bacteria will either be ineffective, or worse yet, cause the infection to worsen ⁷

Antibiotics must be given for a prescribed period of time. Doctors and veterinarians prescribe for a specific amount of time because research data supports that it takes this much time to adequately kill an invading pathogen. So, if people do not comply with giving their birds the entire course because the bird seems to be improving, they risk the possibility that some of the more resistant bacteria are still in the bird’s system. Bacteria can mutate and develop a resistance to the antibiotic. Then the veterinarian has to use stronger antibiotics. Sometimes these work and sometimes they don’t. This can result in an even more virulent infection soon after. If none of these stronger drugs works, the bird may succumb to the infection. ⁷

1.5 Antibiotic Drugs and Their Usages

1.5.1 Table of Commonly Used Antibiotic Drugs

1.5.2 Antibiotic Nomenclature and Tradenames

Most antibiotics have two names: the trade or brand name, created by the drug company that manufactures the drug, and a generic name, based on the antibiotic’s chemical structure or chemical class. Each antibiotic is effective only for certain types of infections. Although there are well over 100 antibiotics on the market, the majority come from only a few types of drugs. These are the main classes of antibiotics: ¹

• Penicillins, such as penicillin and amoxicillin
• Cephalosporins, such as cephalexin (Keflex)
• Macrolides, such as erythromycin (E-Mycin), clarithromycin (Biaxin), and azithromycin (Zithromax)
• Fluoroquinolones, such as ciprofolxacin (Cipro), levofloxacin (Levaquin), and ofloxacin (Floxin)
• Sulfonamides, such as co-trimoxazole (Bactrim) and trimethoprim (Proloprim)
• Tetracyclines, such as tetracycline (Sumycin, Panmycin) and doxycycline (Vibramycin)
• Aminoglycosides, such as gentamicin (Garamycin) and tobramycin (Tobrex)
• Carbapenems, such as imipenem and meropenem
• Glycopeptides, such as vancomycin and teicoplanin
• Lyncomycins (such as Lincocin) ^{1, 48}

1.5.3 Over-the-counter Antibiotics

Many owners decide to save money by purchasing antibiotics from a pet store. Since the owner is unable to diagnose his bird properly, these do little to no good. These water-based medications are so broad-spectrum that they are not effective against a specific bacterium. The bird’s illness cannot be diagnosed without a veterinary exam and culture. Giving these medications causes the owner to waste valuable time in getting the bird the proper medical care. The sick bird’s condition deteriorates quickly—within hours even—once the infection takes hold. Time is of the essence when it comes to getting treatment for sick birds. ⁶

1.5.4 Antibiotic Interaction with Other Drugs and Foods

Many humans use home remedies that seem to work for them, but they should not use them on their birds. They are experimenting and that’s never a good idea. Birds are not mammals. What works on us does not necessarily work for them. It is especially important that they not give their bird home remedies during antibiotic therapy. Some foods can inhibit the efficacy of these drugs. Do not add grapefruit seed extract (GSE) to your bird’s water as an extra med when you are giving them antibiotics. Grapefruit is one of the foods that is well known by doctors to interfere with the absorption of some antibiotics. “Natural” is not by definition safe (not that GSE is natural–it is filled with preservatives). And don’t administer apple cider vinegar thinking it’s a cure-all for birds. It is only used for fungal disease, and even then it is just a temporary fix. The illness will not go away because of its use. It must be treated with the correct medication from the avian veterinarian. ⁷

1.6 Bacterial Resistance to Antibiotics

Antibiotics are typically used to treat bacterial infections. However, in recent years, the improper or unnecessary use of antibiotics has promoted the spread of several strains of antibiotic-resistant bacteria. With antibiotic resistance, infectious bacteria have built up a tolerance for antibiotics that had previously been effective. One such problematic bacterial strain is methicillin-resistant S. aureus (MRSA), a gram-positive bacterium, which resists methicillin and other antibiotics used to treat Staphylococcus infections. It has been found in birds and is quickly fatal. It spreads primarily through skin contact and causes skin infections. ⁵⁴

Some pathogenic bacteria become resistant to antibiotics over time due to mutation. They may work for a while then cease to work after a time. As they change, it becomes more and more difficult to destroy them. This image demonstrates the effect the antibiotic has on bacterial cultures in which it has failed to kill the bacteria. ⁵⁴

Image 6. Antibiotic-resistant strains of Staphylococcus aureus bacteria and Methicillin-resistant S. aureus or MRSA have become the most common cause of skin infections and are frequently found in birds (image courtesy Anthony Komaroff). https://www.askdoctork.com/mrsa-dangerous-201502037412

Image 7. An antibiotic’s effect on various bacteria (image courtesy 123rf). https://www.123rf.com/stock-photo/bacteria_culture.html?mediapopup=47047441)

1.7 Antimicrobials/Antibiotics Commonly Used in Pet Birds

These are commonly administered to avian patients:

Amikacin sulfate

Amoxicillin/clavulanate

Azithromycin

Ceftazidime sodium

Ciprofloxacin

Clindamycin

Doxycycline

Doxycycline injectable, 20 mg/mL

Enrofloxacin

Metronidazole

Marbofloxacin

Trimethoprim/sulfamethoxazole ⁶

1.8 The Use of Probiotics for Avian Patients

Although most antibiotics do kill the good bacteria as well as the harmful ones, most healthy birds will rebuild their supply of normal flora once the infection has cleared up and the bird returns to its usual diet. Owners may wish to give their birds probiotics–lactose-based bacteria that are used by humans to rebuild healthy flora. They are for the most part harmless; however, they are also a waste of money unless probiotics without lactose and made specifically for birds can be found. ⁷ “There is only one good probiotic out there, Sivoy, and it is made in Italy. So, most people will not be able to get it.” (However, Visbiome Vet is available here and is related to Sivoy. Ask your avian veterinarian about it) (R. Dahlhausen, personal communication).

Probiotics made for humans are specific for mammalian flora. Research into developing a true probiotic specifically for birds has been too expensive for most drug companies to pursue. It would have to be cultivated from birds, most likely chickens. Research on human probiotics can be translated from other mammals to humans, but not from mammals to birds. Birds are simply too different. ⁷

The development of antibiotics has changed the course of veterinary medicine. Since their use, countless numbers of birds and other animals have been saved from death by previously fatal diseases and infections. Ongoing research and development of new antibiotic drugs to combat these illnesses is vital.

1.9 Administering Medications Orally

Oral medications must be given directly into the mouth with an oral syringe. Putting them in the water is not a good idea. How much is the bird drinking? Is he drinking less because the water tastes unpleasant to him? Is he drinking more because he is overly thirsty and therefore getting too much medication? The only way to truly determine if your bird is getting the exact, correct dosage is to give it orally. As with children, it can be a struggle with some birds, but it is worth the effort to know he is receiving the correct dosage.⁷

Choose the correct size of oral syringe for the bird. Small birds should receive it from a .5 cc. syringe; medium-sized birds should take it from a 1 cc syringe, and larger birds can use a 1 cc to 5 cc syringe, depending on how well they take the medication. Some large birds are very difficult to dose, so a smaller syringe might have a better chance of getting the medication into them without so much waste. Be aware that you cannot skip dosages without jeopardizing the treatment plan. They must be given as directed by the clinician.

Part II What Are Bacteria and How Do They Work?

2.1 What are Bacteria?

Bacteria are microscopic, single-celled organisms with a simple internal structure that thrive in diverse environments. They can live within soil, in the ocean, and inside the human intestinal system. They contain ribosomes, spherical units within the cell where proteins are assembled from individual amino acids. ⁵⁴

They can be beneficial, as in aiding in digestion, or harmful, causing disease, and they can survive in extreme environments due to their diverse metabolisms. Their ways of obtaining energy for growth and life have allowed them to colonize nearly every environment on earth.³¹ Not all bacteria are capable of causing disease, but each group has at least some disease-causing representatives. ³⁹

Image 8. Ribosomes within the cell (image courtesy Billy Cell City). http://billycellcity.blogspot.com/2009/11/ribosomes-brick-factory.html

2.2 The Difference Between Aerobic and Anaerobic Bacteria

Bacteria may be divided into those which are aerobic and those which are anaerobic.

(Table courtesy Jilani) ²⁹

2.3 Bacterial Structure

Bacteria range in size from 1 to 10 micrometers in length and cannot be seen without a microscope. They have no nucleus, and their genomes are a single circle of DNA.³ On the outside, bacterial cells are usually surrounded by two protective coverings: an outer cell wall and an inner cell membrane. However, some bacteria do not have a cell wall at all, and others may even have a third, outermost protective layer called the “capsule.” ⁵⁴

Bacteria can move in a variety of ways. A number of them move about by secreting a slime that allows them to glide over the cell’s surface so that they slide through their environment. Others have flagella—small, whip-like appendages made of protein which move the bacterium along in a swimming motion. There are those that use pili, hair-like structures, which help the bacterium attach to the host surface. These aid them in “swishing through their watery environments.” ³¹

Image 9. Structure of a bacterium cell (image courtesy Montana Science Partnership). Science Partners.info, http://www.sciencepartners.info/module-3-soils/the-tree-of-life-part-1/bacteria

2.4 Bacterial Reproduction

Most bacteria multiply by binary fission. A single bacterial cell, the “parent,” makes a copy of its DNA and grows large in size by doubling its cellular content. The doubled contents are pushed out to either end of the cell. Then a small fissure emerges at the center of the parent, eventually splitting it into two identical “daughter” cells. Some bacterial species reproduce by budding. During budding, the daughter cell grows as an offshoot of the parent. It starts off as a small nub, grows until it is the same size as its parent, and splits off.³¹

Image 10. Pseudomonas fluoresences reproduces through binary fission. The bacteria splits apart, making almost an exact replica of the parent. Depending on the bacteria’s reproduction rate, there could be  thousands of that bacteria produced in a day (image courtesy Site for Science). https://sites.google.com/site/sassiteforscience/standard-2/objective-d

Image 11. Reproduction by budding (image courtesy mr-roes in Wikispaces).

http://mr-roes.wikispaces.com/Asexual+Reproduction+Webquest

http://fpgeetutor.blogspot.com/2015/02/microbiology-principles-of-microbial.html

Image 12. Reproduction through binary fission (image credit mr-roes). http://mr-roes.wikispaces.com/Asexual+Reproduction+Webquest

2.5 Bacterial Classification and Shape

Bacteria come in many different sizes and shapes, and they are classified by their morphology, or shape and appearance. They can also be distinguished by the nature of their cell walls and by differences in their genetic makeup. ^{4, 7} The three basic shapes of bacteria are: ^{39, 54}

Image 13. Normal cocci and fungal spores in a Gram’s stain swab; the small dots (black arrow) are the cocci and the large smears (red arrow) are fungal spores (image courtesy Bob Dahlhausen; used with permission)

2.5.1 Spherical or Round.

Round bacteria are referred to as cocci (singular, coccus). Cocci can also take their form in different configurations depending on the bacterium and environmental conditions. They can appear as:

• a single bacterium
• combinations of two (diplococcus);
• a linear chain, as in streptococcus;
• a cluster, such as in staphylococcus.

Cocci cause many illnesses Among the more common cocci is Staphylococcus aureus, which appears as a cluster of cocci. S. aureus often grows harmlessly on the skin, but given a chance, can do great damage to the bird’s skin or respiratory system. ^{39, 54}

Image 14. Staphylococcus aureus

Staphylococcus (pl. Staphylococci) is a genus of spherical, gram-positive bacteria which occur in grape-like clusters (image courtesy “Go Pets America”). http://www.gopetsamerica.com/bio/bacteria/staphylococcus.aspx

2.5.2 Rod-shaped or Cylindrical

Cylindrical, rod-shaped bacteria are called bacilli (singular, bacillus). They occur singly or in linked chains. Escherichia coli is a rod-shaped bacterium that normally lives in the intestinal tract without causing disease; however, it can be harmful at other sites, such as in the urinary tract or on the skin. Some strains of E. coli are spread by contaminated food or water. ^{39 54 56}

Image 15. Rod-shaped bacteria. A stylized scanning electron microscopic image of rod shaped bacteria (bacilli). Tetanus, anthrax and botulism are all caused by such bacteria.. (image courtesy Science Photo Library). https://www.sciencephoto.com/keyword/landscape).

2.5.3 Spiral

Spiral or spirilla (singular, spirillum) are rigid, corkscrew-like, spiral-shaped bacteria which can be further categorized depending on how much spiraling they show.³⁹ One such bacterium is Campylobacter which is commonly found in raw poultry. Spiral bacteria can be sub-classified by the number of twists per cell, cell thickness, cell flexibility, and motility. The two types of spiral cells are spirillum and spirochete, with spirillum being rigid with external flagella, and spirochetes being flexible with internal flagella. ^{39, 47, 54}

Image 16. Spiral-shaped campylobacter bacteria (image courtesy “Food Safety Magazine”). https://www.foodsafetymagazine.com/magazine-archive1/aprilmay-2010/control-of-salmonella-campylobacter-and-other-bacteria-in-raw-poultry/

The shapes and configurations of bacteria are often reflected in their names. For example, the milk-curdling Lactobacillus acidophilus are bacilli, and pneumonia-causing Streptococcus pneumoniae are a chain of cocci. ⁵⁴

Image 17: The shapes of bacteria (image courtesy “Slideshare.net”). https://www.bing.com/images/search?view=detailV2&ccid=tw7N4wfv&id=3C37A9DE538B98626059F8943E8F8B6CC56DC8C4&thid=OIP.tw7N4wfvzpPcJcsy2Khu7AEsDh&q=different+types+of+bacteria&simid=608030189621480002&selectedIndex=9&ajaxhist=0

Part III Beneficial and Harmful Bacteria

3.1 Commensal Bacteria: Beneficial

There are many bacteria in the body that are important to health; they protect the host from disease-causing pathogens. ³¹

Commensal bacteria, which are Gram-positive, are usually beneficial. These are commonly found microflora which consist of those microorganisms which live on body parts covered by epithelial cells and are exposed to the external environment, such as the skin and gastrointestinal and respiratory tracts. Some of these bacteria, given the right conditions, can multiply so quickly that they overpower the immune system and become pathogenic, even though ordinarily they are beneficial. The most abundant bacteria are present in the lower part of the intestinal system, and most intestinal bacteria are Gram-negative anaerobes (organisms that live without oxygen). If allowed to multiply to high numbers, these can become pathogenic and will activate the immune system. If the immune system overreacts to these bacteria, there is the risk of inflammation.⁵²

3.1.1 Normal Flora in the Bird’s Body

Any time a bird is ill, bacterial disease should be considered in the list of differential diagnoses (DDx). They are common in pet birds, and almost always due to poor husbandry and nutrition. Neonates and young birds are especially vulnerable. The most commonly found infections are gastrointestinal (GI) and respiratory. These can lead to systemic disease. Normal bacterial flora exist in all companion birds; in small numbers they do not produce disease, but when allowed to grow, they are very dangerous. ²⁶

Image 18. Normal flora in choanal Gram’s stain in author’s cockatiel #1 (image courtesy Bob Dahlhausen; used with permission).

Image 19. Normal flora in choanal Gram’s stain author’s cockatiel #2 (image courtesy Bob Dahlhausen; used with permission).

Image 20. On the fecal Gram stain, author’s cockatiel #1 exhibited an overgrowth of normal bacterial flora. This is indicative of an intestinal imbalance and indigestion (image courtesy Bob Dahlhausen; used with permission).

Image 21. On the fecal gram stain, the author’s cockatiel #2 exhibited a normal number of gram-negative rods; see black arrows (image courtesy Bob Dahlhausen; used with permission).

Normal gut flora in adult psittacines is about 80-100% Gram-positive bacteria, and 0-25% of that is E. coli. Other Gram-positive bacteria found in the psittacine intestine consist of fecal Streptococcus, Staphylococcus, Lactobacillus, and Corynebacterium, to name a few. ⁴⁹

Bacterial infections are common in pet birds, and clinicians should consider them when encountering illness in a bird. Gastrointestinal and respiratory infections are the most frequently seen and can lead to systemic disease. ²⁶.

3.2 General Overview of Pathogenic Bacteria

Bacteria are single-celled microorganisms that lack a nuclear membrane, are metabolically active, and divide by binary fission. They are a major cause of disease in birds. Bacteria may seem to be simple forms of life, but in fact they are “sophisticated and highly adaptable.” ³⁵

Most bacteria are able to multiply very quickly and can live for a long time on a wide variety of surfaces. These organisms exist in everywhere in both parasitic and free-living forms. ²⁶

In general, the bacteria which invade bird species and cause disease are related to the feeding habits of that species. Since most psittacine species are primarily granivorous, their intestinal flora is predominantly Gram-positive. When bacterial disease is observed in parrots and other genera, it is usually, but not always, Gram-negative in nature. ⁴⁴

The intestinal tracts of most healthy birds will contain potentially harmful bacteria. As long as these are small in number, they do not present a problem. But they can grow to larger numbers and create illness when the bird is stressed or immune-compromised, particularly if it is already fighting a concurrent illness.³² The droppings may change from normal color to very green (biliverdinuria) and become watery due to damage to the digestive tract, kidneys and liver. ³⁴

Bacterial inhalation from dust in the air may produce sneezing, eye rubbing, excessive swallowing, yawning and gaping, coughing, and loss or change in vocalizations. Both inhaled and ingested bacterial infections are potentially life-threatening when left unattended. ³⁴.

3.2.1 Obligate, Opportunistic, and Accidental Pathogens

In order to understand the means of identifying pathogens, one must know the types of pathogens that exist. The three categories of bacterial pathogens are:

• Obligate bacteria. This type must cause disease in order to be transmitted from one host to another. They must also infect a host in order to survive, in contrast to other bacteria that are capable of survival outside of a host. Examples of obligate bacterial pathogens include Mycobacterium tuberculosis and Treponema pallidum. ¹⁹
• Opportunistic bacteria. These takes advantage of an opportunity to cause disease. Opportunistic conditions allow the microorganism to activate, begin to multiply, and overwhelm the body’s weakened immune system.¹⁹ Opportunistic bacteria can be transmitted from one host to another without having to cause disease. However, in a host whose immune system is not functioning properly, the bacteria can cause an infection that leads to a disease. In those cases, the disease can help the bacteria spread to another host. Examples of opportunistic bacteria include Vibrio cholerae and Pseudomonas aeruginosa. ¹⁹
• Accidental bacteria. Some bacterial pathogens cause disease only accidentally. Indeed, the disease actually limits the spread of the bacteria to another host. Examples of these “accidental” pathogens include Neisseria meningitides and Bacteroides fragilis. ¹⁹

Most pathogens are Gram-negative, although some are Gram positive. Many pathogens, or harmful bacteria, can exist without causing disease if the numbers are low enough. However, if the numbers increase, they can cause serious diseases and infections such as meningitis, encephalitis, and myelitis. These bacteria include Salmonella, Listeria, S. aureus, Pseudomonas, Klebsiella, Mycobacterium, Streptococcus, Clostridium, and E. coli. These microbes are found everywhere in the environment. ¹⁸

3.2.2 Pathogenic Bacteria Must Be Able to Perform Three Actions:

• They must be able to enter and colonize the body. This happens when the person or animal breaths, eats, or drinks. They can enter through a wound or be passed on through sexual contact. They can also be passed on by parasites which bite an infected individual and then bite another, causing the same disease. ³¹
• They must overcome the body’s defenses. An immune-competent individual is usually able to throw them off, but if a person or animal is immune-compromised, the bacteria will be able to take over. Weakened immunity allows pathogens to reproduce rapidly and thus lead to any number of infections. ³¹
• They must damage the body. Pathogens produce toxins and enzymes that damage the body’s tissues. If food is improperly processed or cooked, or allowed to be out of the refrigerator too long, bacterial toxins can be become part of the food. Clostridium botulinum (botulism) is one such bacteria, often caused by improper canning methods. The toxins, not the bacteria, are what cause disease. ³¹

Image 22. Clostridia bacteria. These are the lines appearing on the image (black arrow) (image courtesy Sandhill Veterinary Services; used with permission). http://www.sandhillvet.co.uk/html/pigeon_service_management_diseases.html

3.3 Causes of Some Bacterial Infections

E.coli Contaminated food old fruit, fluctuating temperatures, draught, stress, wet areas, fungus infection, dirty cages

Streptococcus Cold stress, underlying viral infection, dusty environment, poor seed, stress

Staphylococcus Dust, mice, stress, poor seed, contaminated air conditioning, or dusty environment

Diplococcus Mice, stress

Citrobacter Poor water hygiene

Pseudomonas Poor water hygiene (e.g. bathroom grout and seal around sink) ⁵⁶

3.4 Transmission of Bacterial Infection.

Droplet infection occurs when the person with a cold coughs and sneezes and large numbers of the particles become airborne. The particles contaminate everything they touch, including the bird itself and its surroundings. Infection is due to inhalation or ingestion of the bacteria. Many people allow the bird to come in contact with their mouths; this is dangerous as we carry many bacteria in our mouths that are normal for us but harmful to the bird, such as E. coli. ¹⁹

3.5 Symptoms of Bacterial Infection

“The trachea of a bird connects and seals to the sinuses through the choanal slit when the bird closes its mouth. Signs of upper respiratory or sinus infection are sneezing and nasal discharge. Tail-bobbing and difficulty breathing are due to either middle airway (trachea) or lower airway (lungs or air sac) disease. Birds with a severe upper (sinus) airway disease rarely show much difficulty in getting air in and out of the air sacs and through the lungs. They also don’t usually show systemic signs of illness until and unless the infection extends down into the middle or lower parts of the respiratory system. Their sinuses produce a wet, gurgly sound when their mouths are closed.” ¹⁹

3.6 Types of Bacterial infections

Symptoms depend on the part of the body infected and the severity of the infection. The disease can be peracute or chronic.

• Peracute infection: a sudden, overwhelming illness. The bird sits fluffed up and quiet, and death occurs within 2 – 3 days.
• Chronic infection: The bird fails to thrive for as long as 6 – 8 weeks. With treatment, some birds may recover; others will relapse and die. Some can live indefinitely with treatment, and the disease become transient and mild. ⁵⁵

Part IV Pathogenicity and Etiology of Bacterial Disease

4.1 Classification Based on Pathogenicity

Pathogenicity is the capacity of an organism to cause disease. On this basis, bacteria which have been identified in a patient can be organized into three major groups:

• Primary pathogens. These are considered to be probable agents of disease (e.g., feces are tested and Salmonella spp. is identified as the cause of diarrheal disease).
• Opportunistic pathogens. These enter a host whose immune system has been compromised due to another disease. Bacterial infections can and do occur secondarily to other illnesses or pathogen infections. Viral infections, for example, cause a weakening of the immune system; this permits pathogenic bacteria to enter the body. ³⁴
• Non-pathogens. Some bacteria are considered to be non-pathogenic because they rarely or never cause disease. Pathogenic bacteria constitute only a small proportion of bacterial species, and many non-pathogenic bacteria are beneficial to birds. However, it is possible for non-pathogenic bacteria to adapt and become harmful due to the effects of other therapies on resistance mechanisms. In fact, some bacteria previously considered to be non-pathogens are now known to cause disease.” ³⁵

4.2 How Bacteria are Able to Cause Infection:

• Some bacterial species are extremely virulent and are able to attack a strong, healthy system.
• The bird encounters overwhelming or large-dose exposure to opportunistic bacteria.

Opportunistic bacteria are able to enter the system because of reduced immune response. This occurs during times of stress, poor nutrition, or concurrent disease conditions. Birds experience a great deal of stress some or even all the time. ¹⁹

Image 23: Fecal gram stain from a normal psittacine bird. (Image courtesy G. Kaufman) ³¹

4.3 Septicemia

Image 24: How sepsis takes over the body systems (image courtesy Dr. Warraich Health Channel) https://www.youtube.com/watch?v=qinhrQDtc_I&ab_channel=Dr.WarraichHealthChannel

Septicemia (sepsis or blood poisoning) is a systemic disease which results when pathogenic microorganisms and their toxins enter and remain in the blood. The signs seen by the clinician are a combination of those seen with toxemia and hyperthermia: fever and mucosal and conjunctival petechiation found in the joints, eyes, meninges (membranes around the brain and spinal cord), and heart valves. (Petechiae are minute reddish or purplish spots containing blood that appear in the skin or mucous membrane as a result of localized hemorrhage). Proof is by positive blood culture or smear.⁸

Sepsis, a life-threatening illness, is brought about by the presence of numerous pathological bacteria in the blood which cause the body to respond in organ dysfunction. ³⁵

Image 25. Infection from bite wounds which can let to septicemia. Treatment needs to be aggressive (image courtesy N. Forbes). ²³

4.4 Sources of Infection and Prevention

4.4.1 Bite Wounds from Cats and Other Animals

Bite wounds very often lead to a fatal septicemia if not treated aggressively. The patient should be evaluated for its overall condition and treated appropriately for blood loss or hypotension. The extent of wounds should be evaluated. If the patient’s condition allows, wounds should be thoroughly flushed and fractures stabilized. Aggressive antibiotics should be started early in the treatment. Piperacillin or cefotaxime combined with amikacin or tobramycin are a good choice and should be continued for up to 14 days. If septicemia is suspected, treatment for septic shock should be instituted, i.e., intravenous fluids, rapidly acting steroids, and intravenous bactericidal antibiotics.²³

Image 26. Biliverdinuria and polyuria (excessive urination) in a cockatoo with bacterial septicemia and hepatitis (image courtesy Harrison and Ritchie: Making Distinctions in the Physical Exam, Section 2, Patient Evaluation in: Avian Medicine: Principles and Application, figure 8.41, p. 174, 1994

These are emergency cases which usually require that medications be delivered by parenteral means (other than by mouth) since the bird is unable to swallow them. “Treatment consists of administration of broad-spectrum antibiotics, parenteral fluid therapy, and corticosteroid administration to prevent endotoxic shock due to degenerating gram-negative bacteria.” ²²

Pasteurella bacteria have been reported as possible septicemic agents in birds attacked by pet cats or rats. ³⁰

4.4.1.1 Bartonellosis or Cat Scratch Disease

“Cat-Scratch Fever” is caused by a Gram-negative bacteria known as Bartonella henselae. It is spread through cat scratches and bites. The saliva penetrates the broken skin or mucosal areas such as the nose, mouth, and eyes. Licking by the cat will also transmit this disease. The wound is a puncture wound and it inoculates the bacteria into the skin, and because of the feathers, the owner doesn’t see it, then a few days later the bird is dead. ³⁷

Cats use this toxic bacteria to kill in the wild; the instinct to attack, scratch, bite and claw are built into them. Infants, children, and adults can contract this disease from cats, even young ones. ³⁷

The symptoms include:

• Blisters or papules at the site of the scratch/bite
• Fever, headache, sore muscles, poor appetite
• Heart, eye, brain, intestinal, and skin ailments
• Hyperplasic or swollen lymph nodes, particularly in the armpits and groin
• Malaise
• An enlarged spleen
• Fever, headache, fatigue, muscle soreness and poor appetite.

The diagnosis is often difficult to attain unless the parent is aware of the cat scratch/bite. A biopsy is required to establish a definitive diagnosis. Antibiotics such as Azithromycin are required to destroy the bacteria. Some pathogens are resistant to antibiotics, and this is becoming a serious problem. Most people recover in just a few weeks. In about 5-15% of cases, other, more serious conditions may develop, including heart, eye, brain, intestinal, and skin afflictions. ³⁷

4.4.1.2 Toxoplasmosis

There has been some question about the incidence and potential for toxoplasmosis infection in birds, particularly in pet birds. For the most part, the possibility of pet birds kept in an indoor, hygienic, safe environment is low; however, there are some ways in which even these birds might contract the disease if cats are a part of the household. Many people now keep chickens and other poultry, and these birds are at risk of contracting Toxoplasmosis gonii infection as well. ³⁷

Image 27. A new study reveals that the Toxoplasma gondii parasite acts through the IRE1 protein to cause infected cells to migrate through the body, spreading the parasite (image courtesy Drug Target Review). https://www.drugtargetreview.com/news/65528/toxoplasma-gondii-hijacks-host-stress-mechanisms-to-spread-through-the-body/

4.4.1.3 Toxoplasmosis Symptoms

Toxoplasmosis is a zoonotic (can be transmitted from animals to humans), parasitic, protozoan disease. It is more common in aviaries and backyard poultry than commercial producers. It is characterized by disorders of the central nervous system, but it can also affect reproductive, musculoskeletal and visceral organs (internal organs of the chest and abdomen). Clinical signs include:

• Weight loss and inappetence
• Shrunken comb (in poultry)
• Drop in egg production, whitish diarrhea
• Incoordination and trembling
• Opisthotonos (severe spasm in which the back arches; head is back and tail is up)
• Torticollis or Star-gazing (twisting of the neck)
• Blindness. All chickens infected before eight weeks of age develop clinical signs. In older birds, infection can be asymptomatic (infected hosts show no symptoms) or latent (symptoms only develop under certain conditions). ³⁷

4.4.2 The Growth of Bacteria in Foods

Fruits, vegetables and other soft, moist foods can spoil rapidly, promoting the growth of bacteria (particularly Pseudomonas spp. and E. coli) Clean water with no additives should be provided daily. Vitamins added to the water oxidize quickly (become inactive) and provide an excellent growth media for bacteria. ²⁴ Owners are advised not to add vitamins to water as there can be a 100-fold increase in the bacterial count in 24 hours. Changing the water and rinsing the container will obviously decrease the bacterial load, but an active biofilm remains on the container walls unless it is disinfected or washed thoroughly.³⁸ Pseudomonas leaves a biofilm which is easy to detect and can be extremely harmful. Others, like Staphylococcus aureus, are difficult to detect and can be deadly. ^{24, 38}

Salted, pickled, or cured foods will spoil more slowly and are less likely to grow bacteria.  Remember your temperature guidelines: Keep it hot or cold. Storage in the refrigerator doesn’t prevent spoilage; it merely slows it down.  Porous surfaces promote bacterial growth since they retain moisture.³⁸ Soft foods can become contaminated with high concentrations of bacteria in as little as two to four hours, depending on the food, room temperature, and how old the food is. Food and water containers that have been contaminated with fecal matter will also grow bacteria in a short time. Utensils, storage containers, and towels can all be reservoirs for microorganisms. Don’t keep cooked grains such as pasta for more than a day or two. Freezing smaller portions is a good idea.^{11 38}

Gram-negative bacteria can contaminate seeds, seed mixes, unwashed fruits and vegetables, and even tap water. ⁴⁴ These bacteria are usually associated with water, sand, grit, seed, old food, humid areas, dusty spots and wet cages. Bacterial infections also occur in birds that have a poor level of natural resistance or a damaged immune system. ^{34, 44.}

4.4.3 The Home Environment

Bacterial infections are always related to the environment in which the bird is kept. They usually result from ingestion of the pathogen or contamination in the location. Extra care must be taken to prevent recurrence. From the results of the culture tests, the veterinarian is able to explain the origins of each infection and can advise the client on ways to prevent recurrence. ³⁴

Air conditioners and ventilation systems may serve as foci for bacterial or fungal growth in an indoor facility. In a finch breeding facility, recurrent bacterial infections were traced to an air conditioner filter that supported the growth of Aeromonas sp. ^{14, 22}

Image 28. Contaminated food and water dishes on the bottom of the cage; filthy perches, cage and environment; perfect conditions for bacterial overgrowth (image courtesy Carla Treece Jackson; used with permission).

4.4.4 The Cage Environment

Food and water containers should be positioned away from perches or nest box openings to reduce excrement contamination. In Image 24, the feeding alcove was placed directly under the nest box, resulting in continuous excrement contamination of the food and water. Note also that these birds were on an all-seed diet. The incidence of recurrent enteritis in the breeding adults and Gram-negative bacterial septicemia in the neonates was high in this breeding facility. ^{14, 22}

4.4.5 The Sick Bird

Sick birds should not be left out of the cage unattended; they should be either in their cages or with the owner until they are fully recovered. If allowed to wander around the house and on the floor, they could easily pick up other pathogens. This will protect them from becoming reinfected by bacteria in the environment. They can also pass the illness on to other birds when they are free-roaming. Ill birds are more susceptible to secondary infections. Birds already ill have little cell membrane resistance. ³⁴

4.4.6 The Pet Bird’s Owner and His Family

Pet birds are at significant risk of infection by contact with their owners’ mouths. Most owners are not aware of all the bacteria in their mouths, and most of the time busy veterinarians don’t mention it in the birds’ annual exams.

4.4.6.1 Bacteria Found in the Human Mouth: E. coli

Current research shows that there can be over 600 different bacterial species found in a healthy human’s mouth. The bacteria most commonly found which can cause disease in birds are:

1. Lactobacillus

2. Clostridium

3. Corynebacteria

4. Proteus

5. Prevotella

6. Haemosphilus

7. Pseudomonas

8. Staphylococcus

9. Streptococcus

10. E. coli

11. Enterococcus

12. Mycoplasma

13. Neisseria

14. Actinomyces ⁶¹

Of all the bacteria found in the human mouth, E. coli is the most dangerous. It can be responsible for causing infections in psittacine birds, and it can even penetrate through the pores in egg shells, resulting in dead-in-shell embryos or death of recently hatched chicks. E. coli is identified as one of the most common causes of infection of the oviduct and reproductive tract in parrots.⁶¹

Because of the dangers present in the human mouth, it is crucial that everyone who handles the bird be made aware that kissing the bird on the beak and allowing the bird to kiss and tongue the human’s mouth allows transmission of bacteria to the bird’s mouth, thus providing entry of dangerous bacteria to the bird’s respiratory and gastrointestinal systems. The author has seen multiple videos and images of small birds being allowed to pick the teeth of a human. This practice invites serious bacterial infections in their avian companions. ⁶¹

“E. coli is a very common bacterial organism, found in human mouths at least 25% of the time, and it is also found in dog and cat feces, manure used to fertilize produce and flowers, and in the gastrointestinal tract of many animals we interact with on a daily basis. E. coli has the ability to proliferate uncontrollably outside of its normal home territory of the GI tract. But some strains of E. coli can also cause gastrointestinal disease and diarrhea, often dangerous and potentially fatal, if not identified and treated in time.” ⁶¹ It is diagnosed through cultures, lab tests, and DNA PCR. Blood chemistry tests and complete blood counts will help determine if this bacterium is present and causing the infection. Since this bacterium can survive in dried droppings and dander for a long time, constant cleaning and disinfecting of the environment is mandatory ⁶¹

4.4.7 T. gondii Parasitic Infection

Although this is not a bacterium, it is worth mentioning here as it is a danger to birds and humans. And since it’s a parasite, and can do considerable damage to the skin, bacterial infections can begin to form from the wounds on the bird’s tissues.

“Toxoplasma gondii (T. gondii) is a single-celled parasitic organism that can infect most animals and birds. Because it reproduces only in cats, wild and domestic felines are the parasite’s ultimate host. ¹¹

“The only known definitive hosts for Toxoplasma gondii are domestic cats and their relatives. Unsporulated oocysts (eggs) are shed in the cat’s feces. Although oocysts are usually only shed for 1-2 weeks, large numbers may be shed during that time. Oocysts take 1-5 days to sporulate in the environment and become infective. Intermediate hosts in nature (including birds and rodents) become infected after ingesting soil, water or plant material contaminated with oocysts Cat litter boxes are the primary source of the infection in homes. ¹¹

When a person becomes infected with T. gondii, the parasite forms cysts that can affect almost any part of the body — often the brain and muscles, including the heart. If a person is generally healthy, his immune system keeps the parasites in check. They remain in the body in an inactive state, providing the person with lifelong immunity so that he can’t become infected with the parasite again. But if his resistance is weakened by illness or certain medications, the infection can be reactivated, leading to serious complications. Women who are pregnant should have another person handle all cat droppings. ¹¹

Although an adult can’t “catch” toxoplasmosis from an infected child or another adult, he can become infected if he comes into contact with cat feces that contain the parasite. The person may accidentally ingest the parasites if he touches his mouth after gardening, cleaning a litter box, or touching anything that has come in contact with infected cat feces. Cats who hunt or who are fed raw meat are most likely to harbor T. gondii.” Anti-parasitic drugs are used to counteract the disease. ¹¹

4.5 Disinfection: The Key to Preventing Disease

Clean all food and water dishes daily; this is particularly important if the bird has an infection, but it should be part of the daily cage-cleaning routine. Lysol and dilute bleach are very good at disinfecting. It’s best not to clean with these solutions; just use them as disinfectants after cleaning with detergent or soap and water. The Lysol and bleach have instructions for how long the liquid is supposed to remain on a surface.  And proper dilution is key—straight bleach is very corrosive.   When cleaning bird-occupied surfaces, use 1 part bleach to 10 parts water. Disinfectants and cleaning products all work by different methods, although bleach is pretty much toxic to everything. The owner should wear gloves; inexpensive neoprene gloves are available at hardware stores. ³⁸

Clean and disinfect perches often. Keep the birds away from the cages when you are cleaning them until the cages are completely dry.

Part V: Bacterial Pathogens Commonly Found in Companion Birds

Explanation of Gram’s stains and Gram positive and negative bacteria and other tests will be found in Part VI

5.1 Commonly Found Gram-positive Bacteria

• Staphylococcus, including Staphylococcus epidermidis.
• Streptococcus and Streptococcus intermedius
• Clostridium
• Enterococcus
• Mycoplasma spp (has been implicated in chronic sinusitis and often found in cockatiels)
• Lactobacillus
• Corynebacterium. ^{26, 34}

5.2 Commonly Found Gram-Negative Bacteria

• Klebsiella
• Aeromonas
• Enterobacter
• Proteus
• Citrobacter
• Pseudomonas
• Campylobacter
• Escherichia coli,
• Pasteurella spp
• Mycobacterium and Chlamydia
• Salmonella spp.^{18, 23}

Image 29. Fig 39.24 | A canary with Mycoplasma conjunctivitis CAM: Bacterial Diseases 895-897 Bacterial disease in Passeriformes (songbirds, canaries, finches)

5.3 The Most Dangerous Gram-Positive Bacteria: Staphylococcus and Streptococcus

Staphylococcus (plural staphylococci) and streptococcus (plural streptococci) infections are commonly found in many pet birds and often discussed together. They both will produce severe illnesses that will lead to death. These bacteria are responsible for a wide variety of symptoms, including

• dermatitis,
• pododermatitis (bumblefoot),
• conjunctivitis (red, inflamed eyes),
• sinusitis,
• arthritis, and
• pneumonia

Initial testing is usually with Gram’s stains and cytology, and confirmation of the disease is provided with culture-and-sensitivity testing. ²⁸ Staphylococci, streptococci (especially hemolytic strains), and Bacillus spp are thought to be responsible for several dermatologic conditions in psittacine birds. ²⁶

Image 30. S. aureus with pyloderma grown in a culture (image courtesy Galabin Mladinov гълъбин младенов‎; used with permission)

Image 31. Sinus infection in a cockatiel due to a bacterial infection, probably S. aureus. A scab has formed over the eye and it is likely the orbit has collapsed, rendering the bird blind in that eye (image courtesy Bob Doneley; used with permission). ¹⁸

5.3.1 Staphylococcus aureus and MRSA

Staphylococcus is a genus of spherical, gram-positive bacteria which occur in grape-like clusters. They are a natural part of skin flora in most mammals and birds, and they normally colonize the upper respiratory, alimentary, and urogenital tracts. They are also the most common cause in pus-forming (pruritic) skin infections. S. aureus, commonly found in the nares, and S. epidermidis, found in both the nares and on the skin, have the greatest pathogenic potential. ⁴⁵

Staphylococci are often isolated from lesions of pododermatitis in many avian species. Methicillin-resistant S. aureus (MRSA), previously thought of as rare, is becoming increasingly documented in birds. This bacterium is found in dust, poor seed, contaminated air conditioning, and is carried by mice. It is exacerbated by stress. ²⁶

For a comparison of S. aureus and MRSA, please see Appendix A, p. 75

Image 32. Bumblefoot Caused by S. aureus usually in birds. A pyogranulomatous, chronic infection of subcutaneous tissue on feet. S. aureus is usually introduced via skin lesion on foot (image courtesy Study Blue, Gram positive Bacteria Flashcards | Chegg.com). https://www.chegg.com/flashcards/staphylococcus-c38dfd0f-1879-4025-bc55-d3167c8935da/deck

5.3.1.1 Antimicrobial Resistance of S. aureus

Staphylococcus aureus is resistant to most antibiotics.^{26 “}S. Aureus and Streptococcus have acquired resistance through genetic mechanisms. Many strains of S. aureus are resistant to all clinically useful drugs.” ⁴⁵

Staphylococcus infections generally result in very pruritic (red, itching and pus-filled), often erythematous (red blood cell) infections of the skin. Skin biopsy—including that of feather follicles—and cultures are required to diagnose the illness. ¹⁸

Image 33. Dermatitis in a cockatoo due to staphylococcal infection following a dog ‘mouthing’ the bird (image Courtesy B. Doneley; used with permission).¹⁸

5.3.1.2 Case Study Involving S. aureus

A 2-year-old female Congo African Grey parrot (Psittacus erithacus erithacus) was evaluated for long-standing self-trauma of the feathers and skin of the tail base. All tail feathers and tail coverts were missing, the skin of the tail base was thickened and ulcerated, and the uropygial gland was swollen. There was increased white blood cell count, and x-rays showed shortened caudal vertebrae and pygostyle. Test results of affected areas “revealed ulcerative bacterial dermatitis positive for methicillin-resistant Staphylococcus aureus (MRSA).” ⁹

The bird was treated with multiple medications, topical gel, and hydrotherapy for a month, and there was some tail feather regrowth; however, even though the bacterial infection was resolved, the bird continued to traumatize the area for the next two years. ⁹

Image 34. Staphylococcus aureus (image courtesy Food Science Avenue). https://www.foodscience-avenue.com/2018/01/staphylococcus-aureus-toxin.html

5.3.2 Streptococcus Bacteria

Streptococcus (plural Streptococci), is a disease-causing, Gram-positive bacteria frequently seen in birds. It is found everywhere in the environment, mainly in the dust and air. Many species have been isolated from birds, and they are considered part of the normal bacteria found on the skin and the lining of the digestive, respiratory, and reproductive tracts. ¹⁹

The immune competency of the bird will determine whether or not the bacterial growth increases sufficiently to become a disease agent. ⁵⁵

Some species of Streptococcus are zoonotic. It can be found in humans’ mouths, sinuses, and eyes. ¹⁹

Image 35. Streptococcus pyogenes (image courtesy WikiMili).

Streptococcal infection in poultry – WikiMili, The Best Wikipedia Reader

Group A streptococcal infection – WikiMili, The Best Wikipedia Reader

5.3.2.1 Streptococcus Bacterial Invasion

The streptococcus organism invades the body of a susceptible bird and spreads, first invading the bloodstream from the intestines or skin and then traveling to the other areas of the body. It usually localizes in one specific area initially and then continues to spread. Some of the possible entry areas of the body are:

• The respiratory system, leading to red, watery eyes, nasal discharge, and difficulty breathing.
• The liver, with green diarrhea (biliverdinuria) and weight loss.
• The heart, with long-term cardiac issues and chronic shortness of breath.
• The meninges of the brain, leading to poor coordination, loss of balance, or head tilt.
• The muscles, leading to bleeding and inflammation
• The joints, leading to redness and pain, especially in the wings and legs.
• The kidneys, with increased thirst and urination.
• The intestines, leading to diarrhea
• The abdominal cavity, leading to ascites (fluid buildup) and swelling in the abdomen.
• The reproductive system
  • Young males might experience premature infertility.
  • Hens may experience poor egg formation, leading to embryonic death and weakened chicks that die during or shortly after hatching.

The organism is found in birds’ droppings and can contaminate the nest box and infect the healing navel of recent hatchlings.” ⁵⁵

5.3.2.2 Diagnosis and Treatment of Streptococcal Bacteria

Diagnosis is based on the patient’s history and clinical signs. It depends on the isolation of the bacteria from lesions and cytology findings of streptococcus bacteria in blood films or impression smears of affected tissues. ⁴⁰

Image 36. Streptococci and Enterococci bacteria. Oval cells are arranged in chains end-to-end (image courtesy Medical Microbiology).

Sherris Medical Microbiology, 6e | AccessMedicine | McGraw Hill Medical (mhmedical.com)

Healthy birds living in well-kept environments will be able to resist the disease, and those who do become ill will be able to recover with medication. In an aviary or breeding situation, once the streptococcal disease is diagnosed, the owner must identify and correct the cause of the disease outbreak; otherwise, the medication will not be successful. ⁵⁵

S. aureus will respond to antibiotic treatment. Identification of the organism through culture and sensitivity testing enables the veterinarian to prescribe the most effective antibiotic for that particular strain. Studies show that doxycycline has become the drug-of-choice for most practitioners. It is as effective as synthetic penicillins and more economical. According to Walter, 80% of organisms are controlled by the antibiotics ampicillin (a synthetic penicillin) and doxycycline. ⁵⁵

Image 37. Streptococcal infection in the patagium of the wing of the author’s bird. The bird died from this infection (image courtesy J. Miesle)

5.3.2.3 Preventing the Spread of a Streptococcal infection.

“Streptococcal infections will spread slowly through the flock, resulting in the deaths of some of the birds. Once the disease is confirmed, follow the recommendations below:

• Separate ill birds and treat them in a hospital cage environment (heat, fed and medicated by crop tube, etc.) or euthanize them.
• Keep the aviary clean and disinfected at all times.
• Identify and correct any trigger factors, such as overcrowding, poor diet, poor hygiene, inadequate parasite control, cold or damp conditions.
• Start healthy birds on probiotics. If further birds continue to become unwell while on the probiotic treatment, then treat the entire flock with an antibiotic such as doxycycline.” ^55. “Probiotics will help to minimize the streptococcal invasion during stressful times when normal intestinal bacteria are disrupted; in addition, they may prevent transmission of the infection to other birds.” ⁵⁵

Image 38. A rescued cockatiel taken in by the author. This bird was suffering with a severe sinus infection involving S. aureus.

To view the case study of this cockatiel, please see Appendix B, p. 75

5.4 Enterococcus faecalis

E. faecalis was known as Streptococcus faecalis until 1984 since it was previously categorized by scientists as a bacteria that forms part of the Streptococcus genus. Passerines, or songbirds, such as finches and canaries, are often found with Enterococcus faecalis (formerly Streptococcus bovis) which resides in the alimentary tract. “Birds with this bacteria will present with chronic tracheitis, pneumonia, and air sacculitis, increased respiratory sounds, voice changes, and dyspnea (labored breathing).” ²⁸

Canaries are especially sensitive. Although antibiotics will provide improvement in the clinical signs, many birds never heal completely. ²⁰

Image 39. Enterococcus faecalis (image courtesy Px Pixels). https://pixels.com/featured/9-enterococcus-faecalis-dennis-kunkel-microscopyscience-photo-library.html

5.5 Mycobacterium Avium, or Avian Tuberculosis

Mycobacteria are straight or slightly curved, non-motile, Gram-positive rods. Most birds, including psittacines, are susceptible to M. avium. It is mostly found in high-density populations, such as zoos, breeding facilities, and larger collections. ³ “Mycobacteriosis is an infectious, systemic disease which is chronic and debilitating.” ¹⁵

In the past, antemortem (before death) diagnosis had been challenging, so clinicians had only tests and history to diagnose it. Today, however, clinicians use molecular diagnostic testing since it will afford a definitive diagnosis. ¹⁵ For some birds, diagnosis will not be obtained until the postmortem is performed. ⁴⁹ “Mycobacteria infection leads to a chronic wasting disease. Granulomatous, inflamed lesions on the skin develop that are easily confused with tumor masses.” ²¹

It may be difficult to determine if birds in large collections are infected. The clinician and owner will need to work together to assess the husbandry and sanitation levels in the aviary. It is important to isolate the birds who have the disease or are at risk of contracting this disease. Their weights should be monitored, and CBCs and fecal, acid-fast stains or PCR testing should be performed. ²⁶

Image 40. Cutaneous form of avian tuberculosis in collared dove (image courtesy Datashare).

Image 41. Avian tuberculosis in a woodpigeon. Large, cream, raised nodules throughout liver (image courtesy Datashare).

5.5.1 Vulnerability

Several species of birds are highly susceptible to the disease: gray-cheeked and canary-winged parakeets (Brotogeris pyrrhoptera), Amazon parrots, pionus, finches and canaries, and some species of Forpus parrots (parrotlets). This disease is endemic in these populations, making the birds predisposed to acquiring it; for them it can be quite debilitating. Softbills and passerines are highly susceptible to mycobacterial infections as well. ^{21, 26, 49}

Image 42. Avian mycobacteriosis (image courtesy N. Forbes). ²³

Image 43, Mycobacteriosis in the lung (image courtesy VMD labs; used with permission). http://www.vmdlabs.com/ada-Mbac.html

Image 44. Mycobacteriosis in the duodenum (image courtesy VMD labs; used with permission). http://www.vmdlabs.com/ada-Mbac.html

Mycobacteriosis is one of the most common diseases of various species of birds including domestic poultry, pet and exotic birds such as psittacines and canaries, and free-living and captive wild birds. The disease in birds is generally caused by Mycobacterium avium, but more than 10 other species of mycobacteria have been known to infect birds. These include M genavense, M. tuberculosis, M. bovis, M. gordonae, M. nonchromogenicum, M. fortuitum subsp fortuitum, M. avium subsp hominissuis, M. peregrinum, M. intermedium, M. celatum, M. intracellulare, M. avium subsp paratuberculosis, M. africanum, and M. simiae.

5.5.2 Transmission

M. avium-infected fecal matter, once aerosolized, will be put into the air in large amounts. The infected birds will shed this, and it is then transmitted by ingestion and inhalation. ³

The organism enters the body through the oral, respiratory, and dermal routes. “If the organism enters by ingestion, in will invade the intestinal tract, causing bacteremia, and spread to the liver and other organs.” ¹⁵ Ingestion of the bacteria through contaminated food or water and fecal matter is the most common mode of transmission. ¹⁵

The incubation period for birds is weeks-to-years. The bird will develop pulmonary lesions if the bacterium is inhaled, and skin disease may also develop. It is possible that the bacterium is spread vertically, from hen to egg, but that mode of transmission is not common. ³

5.5.3 Symptoms

Since Mycobacteriosis is difficult to diagnose in its early stages, it should be considered as part of the differential diagnoses when these symptoms are observed:

• Weight loss in spite of good appetite
• Emaciation and muscle wasting
• Loss of subcutaneous and intracoelomic (internal) fat
• Poor-quality integument and skin
• Diarrhea and green urine
• Dyspnea
• Seizures
• Lesions in the lungs and air sacs from inhalation
• Paralysis and lameness
• Depression
• Increased thirst and urination
• Abdominal distention
• Respiratory distress
• Decreased egg production. ^{3, 15}

“Strong indicators of the disease are:

• Subcutaneous granulomas (small, inflamed growths under the skin)
• Organomegaly (enlarged organs)
• A profound leukocytosis (elevated number inflamed white blood cells)
• The cytologic presence of acid-fast bacteria
• Masses and ulcers with enlargement of joints, especially for those with negative results for fungal and aerobic/anaerobic bacteriologic cultures.” ¹⁵

5.5.4 Testing

Several tests may be performed to determine the bacterium. “PCR assays will detect the actual disease-causing organism, and ELISA assays will detect specific antibodies for M. avium. PCR assays are considered to be the fastest, most sensitive method for detecting M. avium, while ELISA assays help determine exposure to M. avium.”³ Molecular methods are highly sensitive and specific for confirming the disease in a short amount of time. ¹⁵

“Endoscopy allows for direct visualization of infiltrative lesions in the abdominal cavity and respiratory tract.”^3,15 With it, clinicians are able to:

• “Identify lesions on the serosal surface of the liver, spleen, intestine, lung, and air sacs.
• Visualize granulomas as white, yellow, or tan, round masses which are soft and easily biopsied. Visualize enlargement of the liver, kidneys, and spleen.
• Take samples of abnormal tissues or granulomas to confirm the diagnosis of mycobacteriosis.
• Remove samples of lesions for cytologic or histopathologic examination, acid-resistant staining, culture, and molecular tests. Examination of the liver is crucial when diagnosing avian mycobacteriosis.” ¹⁵

5.5.5 Treatment

The antibiotic used is determined by the bird’s age, species, and bacterium found. Azithromycin is the drug of choice. It can take six to twelve months to resolve the disease, and relapses are common. Owner commitment is essential since the bird will need daily dosing. Keeping the flock size low and the stress levels reduced will minimize the impact on the collection. Young birds still hand-feeding respond well with oral medications, whereas adult birds respond better to injectable therapy. Combinations of antibiotics (typically three) are recommended because many mycobacterial organisms develop antibiotic resistance. Birds with advanced disease and granuloma formation have a poor prognosis. ^{26, 49}

5.5.6 Prevention

Preventing M. avium is best done by minimizing stress and overcrowding and by providing proper ventilation and nutrition. M. avium outbreak in zoos, bird gardens, and private aviaries can be especially difficult to eradicate. New additions to the aviary should be quarantined for a minimum of 1-2 months. New additions to the flock should be tested to prevent outbreaks^{. 3}

5.5.7 Necropsy and Pathology

Although rare, sudden death might be an indication of mycobacteriosis. Generally, though, “acute death from mycobacteriosis is unusual.”¹⁵ Biopsies of the liver, GI tract, spleen, and lungs will diagnose the disease at necropsy ³

Pathology results include:

• “Emaciation
• Absence of subcutaneous and internal fat
• Severe atrophy of the pectoral muscles
• Hepatomegaly and splenomegaly (enlarged liver and spleen)
• White or yellowish nodules in the lungs, spleen, intestine, air sac, bone marrow, and more rarely, the heart, gonads, central nervous system, skin, and joints.

Hematologic (blood) changes reflecting chronic inflammation and anemia. ¹⁵

5.6 Yersinia pseudotuberculosis

Yersinia pseudotuberculosis is a common cause of outbreaks of acute illness and mortality, usually in aviary parakeets. It is transmitted via feces from infected rodents and wild birds. The majority of affected birds die within a few days, having shown signs of pneumonia, enteritis with wet diarrheic droppings, and general ill health. At post-mortem examination, the most acute cases have an enlarged, patchily discolored liver, and more chronic cases have miliary white spots throughout the liver, kidneys and spleen. ⁵³

In a living bird, confirmation by bacteriology is needed, and antibiotic treatment is required. The drinking water must be kept uncontaminated, and the water should contain either the appropriate antibiotic or a disinfectant, such as 5–6 mg/L of free iodine or chlorhexidine. Prompt treatment will limit, but not completely prevent, deaths in the affected birds. The organ damage in some individuals will cause their deaths even in the absence of the organism. ⁵³

Image 45. Miliary granulomas as seen on this canary’s dark and swollen spleen are indicative of Yersinia pseudotuberculosis (image courtesy Clinical Avian Medicine, Chapter 39, p. 897 figure 39.26

Canaries and finches, particularly in Europe in the winter, may be found with the infection. Signs include ruffled feathers, debilitation, and high mortality. At necropsy, a dark, swollen, congested liver and spleen with small, yellow, focal bacterial granulomata are often found. Diagnosis is confirmed after culturing the microorganisms. Amoxicillin via drinking water is the antibiotic of choice. Soft foods are recommended. ⁵³

Mynahs are very susceptible to yersiniosis, and mortality can be high due to a peracute pneumonia. Post-mortem examination demonstrates hepatomegaly, sometimes with small white foci, splenomegaly, and an acute-to-peracute pneumonia. In Europe, a formalin vaccine is available that appears to be clinically effective in reducing the prevalence of infections. ⁵³

5.7 Escherichia coli

Image 46. E. coli bacteria (image courtesy S. Weir) ⁵⁶

Escherichia coli exists in small numbers in the intestinal tracts of many species of birds, and only if the numbers rise is there a problem. Symptoms vary from species to species. E. coli infections are classified as primary or secondary: A primary infection causes disease by itself, and a secondary infection has an underlying cause. “Most infections are secondary to such stressors as a heavy molt, coccidia, adenovirus, canker, intestinal worms, crowding, stressful home conditions, and poor nutrition.” ⁵⁶

Contaminated food, fluctuating temperatures, drafts, stress, wet areas, fungal infection, and dirty cages are some of the most common causes. ^{26, 34}

5.7.1 E. coli Diagnosis and Treatment

Diagnosis of E. coli infection is based on the symptoms. These are:

• Enteritis and necrotic enteritis
• Loose, green droppings (biliverdinuria)
• Crop stasis
• Vomiting and weight loss
• Sudden death due to septicemia

E. coli, like salmonella, may result in joint infections which present with lameness, swelling, or a drooped wing. Immediate attention to these signs is necessary to prevent further joint damage from occurring. ⁵⁵

Gram-negative bacteria are usually associated with disease in birds; however, the number of bacteria in the intestines differs among species, and some are not pathogenic. Neotropical birds, such as amazons, “may have little to no E. coli in their systems, while some species, such as cockatoos, lories, and eclectus parrots, may have as much as one-fourth of their total flora comprised of E. coli.” ³⁵ As long as the number of bacteria is low, most clinicians believe there is no need for treatment if the bird is not showing clinical signs, but if the bacteria are found in chicks and juveniles, the clinician should perform more tests and begin treatment. ⁴⁹

Image 47. Dropping from a bird with hemorrhagic enteritis, cultured E. coli. Bleeding from an infection/inflammation in the lower intestinal tract (image courtesy M. McMillan: In: Diseases of Cage and Aviary Birds. Ed. Margaret Petrak.1982)

Some strains of E. coli are quite resistant to antibiotics. Commonly used medications are azithromycin, Baytril, Cipro, or Bactrim. These are not to be used on birds that are breeding. The underlying cause of E. coli must be found and treated or the bacteria will return. ⁵⁶

5.8 Campylobacter

Campylobacter is a genus of bacteria of the family Spirillaceae. It is a spirally curved, motile, Gram-negative, rod-shaped bacterium which is pathogenic in domestic animals and humans. Wild and domestic birds are considered major reservoirs of Campylobacter bacteria. It has been found in 35% of migratory birds, 50% of town-dwelling pigeons, and 20%-70% of gulls. It is most commonly found in poultry; therefore, eating undercooked or raw chicken will cause illness in humans and animals.^{12, 40}

Image 48. This shows the curved shape of Campylobacter species (arrow A showing curved gram negative bacteria, arrow B showing white blood cell) stained by gram stain using 0.3% as counter stain. Original magnification X100 (image courtesy Jeremiah Seni, Research Gate). https://www.researchgate.net/publication/271214444_Evaluation_of_detection_methods_for_Campylobacter_infections_among_under-fives_in_Mwanza_City_Tanzania/figures?lo=1

.
Image 49. Campylobacter jejuni (image courtesy Go Pets America). http://www.gopetsamerica.com/bio/bacteria/campylobacter.aspx

The species most often seen in enteric disease in avian species is C. jejuni. Infected birds may be asymptomatic or show the following signs:

• Anorexia
• Somnolence
• Diarrhea
• Emaciation ⁴³

5.8.1 Transmission and Diagnosis

This bacterium is fatal in very young birds. Transmission is by direct fecal or aerosol contact, contaminated fomites (things which other birds have touched), or infected vectors (an organism such as an insect that transfers the bacteria from one animal to another). Diagnosis is made by microscopic examination of the droppings using Gram’s stains. ³¹

5.9 Clostridium

Clostridia are anaerobic, gram positive, spore-forming bacteria. Members of this genus resemble large, straight, or slightly curved rods with rounded ends. Clostridial organisms are common secondary invaders of damaged cloacal tissue in birds with cloacal prolapse or papillomatosis. Different species of clostridia can cause specific disease syndromes. ²⁶

Image 50. Clostridium perfringens (image courtesy University of Arizona, College of Agriculture). https://cals.arizona.edu/pubs/general/resrpt1998/clostridium.html

Image 51. Gram positive clostridium botulinum, or bacillus botulinus (image courtesy Pixnio.com) https://pixnio.com/science/microscopy-images/botulism-clostridium-botulinum/gram-positive-clostridium-botulinum-formerly-known-as-bacillus-botulinus

Image 52. Clostridium in a 7-year-old Moluccan cockatoo presented for smelly stool. In the bacteria field there were 90% gram-positive rods, 10% gram-positive cocci, and 30 Clostridium sp. organisms (image courtesy Merck Veterinary Manual). http://www.merckvetmanual.com/exotic-and-laboratory-animals/pet-birds/bacterial-diseases-of-pet-birds#v4631674

Image 53. Microscopic illustration of rod-shaped bacteria such as Clostridium (image courtesy 123rf) https://www.123rf.com

5.9.1 Endotoxin Release

Clostridium perfringens is the species most often seen in psittacine birds. C. perfringens secretes strong exotoxins that can cause necrosis (cell death) of the surrounding tissue, including muscular tissue. The bacteria “produces gas that leads to bubbly deformations of the infected tissue.” C. perfringens will destroy intestinal tissue, and the enterotoxins lead to severe diarrhea. ²

Image 54. Gas in a bird’s droppings is never normal. Here, diarrhea is caused by gas-producing bacteria (image courtesy Avian Biotech). ²

The clostridia toxins in the small intestines produce these symptoms:

• Decreased appetite and rapid weight loss
• Loss of body condition
• Lethargy
• Blood-stained or undigested food. ²

The toxin and its effects may continue to be in the bird’s system for quite some time, even after the infection has been resolved. ²

Image 55. Clostridial Enteritis (image courtesy Todd Driggers; used with permission).

Yellow blotches: slide artifacts; Purple blotches: degenerating white blood cells; Blue rods: non-sporulated clostridial rods; oval green blotches with black centers: red blood cells

5.9.2 Transmission

Transmission is by ingestion and wound infection from spores found on contaminated surfaces. The spores may also be inhaled or be on contaminated feed, water, fecal material, air, soil, and nesting material. ² Infection may be avoided by:

• Minimizing stress and overcrowding
• Providing proper ventilation
• Preventing malnutrition with a proper diet. ²

Storing food properly in containers will prevent bacterial growth. Corn and grain products, and even pellets or extruded food, may be contaminated by bacterial spores if conditions are favorable. It is wise to freeze all food coming into the house until it is used. ²

5.9.3 Diagnosis and Treatment

Gram’s-stained smears and anaerobic cultures are used to identify clostridial organisms. Samples from affected tissue are used, “including the greenish-brown focal areas of necrosis in the liver. Large, gram-positive cells are almost certain to be clostridia, especially if spores are seen.” ²⁶

Antitoxins and antibiotics, such as Guanidine, zinc bacitracin, penicillin, and tetracyclines are used to treat this bacterium. ²

5.10 Salmonella typhimurium

Image 56: Salmonella bacteria (image courtesy Avian Biotech). ²

Image 57. Salmonella growing on XLD agar (image courtesy Nathan Reading on Flickr [CC-BY-2.0], via Wikimedia Commons.https://www.yourgenome.org/facts/what-is-salmonella

Salmonella species are gram negative, aerobic, rod-shaped, zoonotic bacteria that can infect people, birds, reptiles, and other animals. ⁴

Salmonella typhimurium is the organism most frequently seen in psittacines. Clinical signs are severe illness followed by acute death from septicemia. Rodent feces are a source of contamination in the aviary, and rodents will contaminate food supplies and nest boxes; they will carry contaminants from their own nests to the aviary. ⁴⁹

5.10.1 Infection and Transmission

Infection from S. typhimurium can result in high mortality of young birds. Transmission among birds is primarily through the air. “The organism remains stable outside the host body and dries as a dusty substance.” ⁴ This contaminated dust becomes airborne and enters other birds’ respiratory systems by direct contact of aerosolized fecal matter or feather dust. Affected birds may become symptomatic or be carriers. Transmission is also by ingestion of contaminated food or water, or through shedding the organism in nasal and ocular secretions. Degree of infection depends on the bacteria levels, their serotype, and the age, species, and condition of the host. Birds may have peracute, acute, chronic, or subclinical infection. ²¹

The susceptibility of the bird and number of spores in the environment determine whether or not the bird will become infected. The young may become infected through regurgitation from the hen’s crop during feeding.²¹

5.10.2 Clinical Signs and Susceptibility

• Depression
• Lethargy
• Anorexia, diarrhea, and weight loss
• Conjunctivitis
• Pasty vents
• Lameness
• Abscess formation
• Convulsions
• Poor hatching or excessive fledgling mortality
• Dehydration and crop stasis
• Meningitis
• Liver, kidney, spleen and heart damage and lesions
• Osteoarthritis
• Sudden death.
• Pneumonia and excessive mucus in the nose or throat with inflammation of the mucous membrane.
• Hemorrhagic enteritis ^{4, 21}

Some avian species have specific clinical symptoms. Lories (Loriidae) suffer acute disease and high flock mortality. African Greys tend to develop chronic disease, and their symptoms are mucus discharge from the beak/nasal area, arthritis, excessive thirst, and dermatitis. “Droppings are colored a sulphur yellowish green which is very much a diagnostic sign for this microorganism.”  ⁴

5.10.3 Transmission and Diagnosis

Transmission from hen to egg (vertically) is possible. If this occurs, chicks will hatch and spread salmonella by direct contact with other birds. If the bacteria level is high, the embryo will die. “The disease has a greater chance of spreading in overcrowded conditions, stale air environments, nest-boxes, and brooders. Pet shops, bird marts, and quarantine stations are also high-risk areas.”  ²

In the past, fecal and affected organ culture-and-sensitivity testing have been used to diagnose and treat salmonella. Antemortem diagnosis by fecal cultures is difficult because the bacteria is shed intermittently. ²¹ Today, these assays have been replaced by PCR and sequence assays which are more reliable and identify the strains more precisely.⁴ Even with prolonged treatment (3–8 weeks), the organism might not be eliminated. This disease is controlled only with “strict isolation, vector control, and appropriate disinfection.” ^{4, 21}

Image 58. Salmonella typhimurium (image courtesy Pathogen Profile Dictionary). http://www.ppdictionary.com/bacteria/gnbac/typhimurium.htm

5.10.4 Prevention and Treatment

To prevent outbreaks of salmonella, it is important to keep the birds’ environment meticulously clean. Effective control of flies, rodents and other vermin is essential to eliminate and prevent salmonella outbreaks. Companion birds may be infected by humans who carry the bacteria. African greys, Amazons, cockatoos, and macaws are especially at risk. ⁴ Hanamycin, Gentamycin, and trimethoprem/sulfamethoxazole are used to treat this disease.

5.11 Chlamydiosis. (Ornithosis or Parrot Fever in Birds, Psittacosis in Humans)

Chlamydiosis is the most important zoonotic disease of psittacines. It is endemic to the U.S. and in the wild population.³⁰ Macaws, cockatoos and Amazons are particularly vulnerable to this bacterium. It is also found in cockatiels, budgerigars, and parrots. ^{26, 33}

Chlamydia psittaci is an obligate, intracellular bacterium that can infect all companion birds. The incubation period of C psittaci is from three days to several weeks. The organism can remain infectious in organic pus for about one month. ²⁶ The severity of the disease in the bird depends on the virulence of the organism and the competency of the bird’s immune system. ^30.

“Chlamydophyla depends on amino acids and the host’s cells for its energy supply. The bacterium targets epithelial cells of the mucus membranes of the respiratory system and digestive tract.” ⁴⁶

Image 59. Chlamydia psittici in the air sacs (image courtesy Veterinary Molecular Diagnostic Labs; used with permission). http://www.vmdlabs.com/ada-Chlam.html

5.11.1 Diagnosis

Diagnosis of C. psittaci is difficult, particularly if the bird is asymptomatic. History, clinical signs, radiographs, CBC’s, chemistry panels, and cloacal and choanal cultures have been used in the past, but now serology and PCR testing have proven more reliable. ^{26, 30}

5.11.2 Transmission

For now, there is not a test to show if a previously infected bird is free of the disease. It is transmitted through aerosol inhalation and ingestion for the most part. ²¹ Birds may initially be asymptomatic, but stress can cause acute illness. These birds will infect other birds and humans by shedding the organism. Cockatiels are thought to be one of the most common asymptomatic carriers of C. psittaci. ³⁰ Because it is a zoonotic disease, federal regulations require it to be reported. ²⁶

5.11.3 Symptoms

Birds may be asymptomatic carriers, or they may have severe disease. Clinical signs may include:

• Chronic ocular, nasal, or conjunctival irritation and discharge
• Anorexia, dyspnea, dehydration and polyuria
• Depression
• Biliverdinuria (dark green stools and urine) (hepatitis)
• Hepatomegaly, splenomegaly (enlarged liver and spleen), or air sacculitis.
• Upper respiratory signs (conjunctivitis/sinusitis/rhinitis, often seen in cockatiels)
• Vomiting, lethargy, chronic diarrhea, weight loss
• CNS signs at late stages of the disease which include opisthotonos (arched back), tremors, and convulsive movements
• Leg paresis or paralysis
• Sickly, unthrifty bird with repeated episodes of illness.
• Poor feather coat ^{21, 26, 30, 33}

Image 60. Chlamydia – Direct imprint from air sac with DifQuik stain showing an initial body (image courtesy G. Kaufman) ³⁰

Image 61. This impression smear, made from the exudate of infected tissues, shows intracytoplasmic inclusions associated with Chlamydophila psittaci. Histopathology image from a turkey (image courtesy Cornell University). http://cidc.library.cornell.edu/vet_avian/images/Chlam-Adjusted/CHLAM-022A.jpg.infection. https://partnersah.vet.cornell.edu/content/chlam-022ajpg

Image 62. Chlamydia Psittici in a cockatiel (image courtesy Edgeworth Animal Medical Center). https://www.edgeworthanimalmedical.com.au/2017/05/05/avian-chlamydiosis-and-psittacosis/

Image 63. Photomicrograph of Chlamydophila inclusions in macrophages (arrow) in an Amazon parrot.. Giemsa Stain was used (image courtesy Brazilian Journal of Veterinary Pathology).

5.11.4 Treatment

Doxycycline and azithromycin are the drugs of choice for Chlamydia infection. It is unknown exactly how long it takes to eliminate the organism from the body; therefore, it is recommended that the bird be treated for 45 days. ²⁶

Image 64. Dropping from a cockatoo with psittacosis (image courtesy Cockatoo Info.) http://cockatoo-info.com/health/chlamydia-psittacosis/

Image 65. A Bourke parrot with conjunctivitis caused by Chlamydiosis (image courtesy Melbourne Bird Vet; used with permission). http://birdvetmelbourne.com/chlamydiosis/

Other drugs that have been used to treat Chlamydia in birds are:

• Tetracyclines. They are very effective but work only during the active dividing stage of the organism. For this reason, prolonged therapy for 45 days is required. Even after successful treatment, you can never guarantee a bird free of the organism.
• Chlortetracycline. Treatment through the drinking water is not acceptable.
• Fluoroquinolones are very effective against this organism. ³⁰

For more information, see https://www.beautyofbirds.com/psittacosis.html

5.12 Bordetella avium

Bordetella is a gram-negative, aerobic, coccobacillus bacterium of the Bordetella genus. This rod-shaped bacterium is non-motile and non-spore-forming. B. avian causes the avian disease, bordetellosis, which is responsible for respiratory tract infections in turkeys and in wild and domesticated birds. ³⁶ It is most commonly seen in birds between the age of 2-8 weeks. Turkeys are thought to be the natural host, however; the disease has also been seen in chickens and ducks. ⁶⁰

Image 66. Bordetella avium in a cockatiel (image courtesy Veterinary Molecular Diagnostic Labs; used with permission). http://www.vmdlabs.com/ada-Bord.html

“B. avium colonizes the epithelium of the cockatiel’s tracheal mucosa. As the disease progresses, it will destroy this outer layer of tissue along the respiratory tract and produce toxins that can affect other groups of tissue in the body. It is not zoonotic to humans.” ⁶⁰

As it damages the upper respiratory tract of the bird, it leads to secondary infections from E. coli or other bacteria, causing a more severe infection. If the bird is infected solely with B. avium, he may recover in 4-6 weeks with treatment. Without treatment, the disease will destroy the epithelial tissue in the trachea, causing the bird to die from suffocation. ²⁷

5.12.1 Transmission

Bordetella is highly contagious and easily transmitted by direct contact. It is doubtful that it is airborne because birds near an infected bird will not get the disease. ²¹ It can also be transmitted through contaminated drinking water, feed, bedding, housing, and litter and can remain infectious for 1–6 months in contaminated litter. ²⁷

Image 67. Bordetella avian (image courtesy Look for Diagnosis). https://lookfordiagnosis.com/mesh_info.php?term=bordetella%20avium&lang=3

5.12.2 Symptoms

Signs appear suddenly and include:

• Sneezing and coughing, mouth breathing and dyspnea
• Foamy conjunctivitis around the medial canthus (where the tear duct is) of the eye .
• Sinusitis with a clear nasal discharge that can be observed when pressure is applied to the nares
• Tracheal rales (rattling sounds) and altered vocalization
• Air-sacculitis in advanced disease

In a study of B. avium in cockatiels, it was reported that the bacteria does not appear to cause disease in adult cockatiels; however, it has a severe effect on the very young cockatiel ⁶⁰Symptoms of this disease that are specific only to the young and unweaned cockatiel are:

• “Sneezing with significant mucoid exudates (serious nasal discharge)
• Lethargic behavior and pasty, pale appearance
• Inflammation of the skeletal muscle responsible for opening the beak; this creates the ‘lock-jaw’ condition as the beak gradually closes over a period of 12-24 hours to a point of being ‘locked’ shut (temporomandibular rigidity)
• Constant begging for food, dehydration, and weight loss
• Protruding eyes that appear glassy and half-shut. This is due to swelling of the suborbital chamber of the infraorbital sinus, which forces the lower eyelid upward.
• Swollen appearance of the head due to inflammation of the skeletal (voluntary) muscles adjacent to the inflamed nasal cavity and infraorbital sinus.” ⁶⁰

Birds may exhibit symptoms from three days to four weeks old. Breeders with these signs are considered carriers. Testing is the only way to know if a bird is a carrier. Cockatiels suffer a higher mortality rate from bordetellosis than any other species so far studied and reported. ⁶⁰

At necropsy, birds have watery eyes and extensive mucus in the sinuses and trachea. There may be some hemorrhaging in the lining of the trachea. Signs of the disease usually occur seven to ten days after infection. ²⁷

5.12.3 Testing and Treatment

Serology tests such as ELISA and PCR will provide an antemortem diagnosis. ³⁹ Antimicrobial agents by aerosol, injection, or in the water have not generally been effective, even though B. avium appears to be highly sensitive. “The respiratory area is difficult to medicate, and some strains of B. avium are resistant to antibiotics.” ¹⁹ A necropsy will identify lesions in upper respiratory tract, and this will confirm the diagnosis. ⁶⁰

Image 68. Bordetella avium in the trachea, 7 days after infection (image courtesy M. Jackwood). ²⁷

5.13 Pseudomonas aeruginosa

“Pseudomonas infection is one of the most stubborn and elusive causes of respiratory problems in birds.” ³² It is a mucoid infection, and its causes are malnutrition and poor water hygiene. It is a gram-negative, rod-like organism that is not normally found in healthy birds, but when it is, it is highly resistant to many antibiotics. The body’s warm, moist respiratory system is the perfect place for the spores to grow. This bacterium is frequently found in bathrooms, around the sink, and on the tile grout. ³²

5.13.1 Testing

P. aeruginosa can usually be found in both choanal and cloacal cultures. If the numbers are low, and the bird is not showing clinical signs, treatment is usually not necessary; however, if it is found outside the GI tract, or in the choana/oropharynx, it can cause serious disease. ³²

Other forms of P. aeruginosa infection are conjunctivitis and consequent keratitis and panophthalmites (inflammation involving all the tissues of the eyeball). ¹⁷

Image 69. P. aeruginosa in a chicken (image courtesy I. Dinev). ¹⁷

Pseudomonas is found in water supplies and can cause illness if it is present in high concentrations. Swamp-coolers and hoses that are allowed to sit for prolonged periods without flushing before water is dispensed can aerosolize the bacteria and be sources of contamination.⁴⁹ Other sources are dirty water, dirty bowls, sipper tubes, water systems, misters, spray bottles, baths, sprouted seed, and filters that purify aviary water Cultures must be performed on taps, surfaces, and other areas that the water may contact. Even if bottled water is used, the inside of the cap may contain the bacteria. ³²

The rate of recurrence of the infection is very high, making constant retesting necessary. The bacterium becomes stronger and “more resistant to antibiotics with each subsequent generation.” ³²

5.13.2 Symptoms

• “Sneezing and clear or yellowish discharge from one or both nostrils
• Scratching at the nares and ears
• Conjunctivitis
• In psittacine chicks, it is often associated with chronic sinusitis and usually related to an initial aspiration event.
• Swollen sinuses around the eyes and complete obstruction of the nostrils in severe cases
• Crusty feathers around the nostrils—an early sign
• Foul-smelling diarrhea
• Necro-purulent pneumonia (pneumonia producing inflammation and pus)” ³²

Image 70. Scanning electron micrograph of Pseudomonas aeruginosa bacteria (image courtesy T. Margolin) ³²

5.13.3 Treatment

The preferred treatment is with injectable antibiotics. Most adult birds have competent immune systems and can fight off the infection; however, juvenile psittacines are at greater risk of developing the infection when exposed. They are unable to contain the bacteria to the respiratory tract; therefore, “their systems may be overwhelmed and become septicemic. Hand-fed chicks will succumb to the disease if their formula water is contaminated. Water must be boiled before use and utensils must be disinfected.” ²²

5.14 Bacterial Sinusitis

Bacterial sinusitis causes a collapse of the sinuses. This condition occurs most often with Pseudomonas or Bordetella sp. infections. It responds well to antibiotic therapy based on culture-and-sensitivity testing. Symptoms include “copious amounts of mucous exudate in the sinuses and requires vigorous flushing with large quantities of saline through the sinuses to dislodge the exudate.” ²³ Treatment for these birds includes flushing with 60 ml of saline through each naris daily; this continues until the sinuses returned to normal. The exudate will be flushed out of the choana. The condition is most often seen in recently imported macaws. This condition may also occur if the nares become plugged with a rhinolith and the bird is prevented from breathing normally. ²³

Image 71. Distended infraorbital sinus infection in a parakeet (image courtesy Louise Bauck). ²⁶

Image 72. Sinusitis/conjunctivitis in a cockatiel with Chlamydia sinus infection (image courtesy Melbourne Bird Vet; used with permission).

Bacterial diseases are common in pet birds and should be considered in the differential list of any sick bird. Inappropriate husbandry and nutrition are often contributing factors; neonates and young birds are especially susceptible. GI and respiratory infections are most common and can lead to systemic disease. Normal bacterial flora of companion birds includes Lactobacillus, Corynebacterium, non-hemolytic Streptococcus, Micrococcus spp, and Staphylococcus epidermidis. ²³

“The most commonly reported pathogens are gram-negative bacteria: Klebsiella, Pseudomonas, Aeromonas, Enterobacter, Proteus, and Citrobacter spp, E. coli, and Serratia marcescens). Pasteurella spp have been reported as possible septicemic agents in birds attacked by pet cats or rats. Mycobacterium and Chlamydia are common intracellular bacterial pathogens. Infections with Salmonella spp are occasionally seen. ²³

Image 73. Serratia Marsecens on MacConkey agar (image courtesy Kayleigh Griffin; used with permission).

“The most common gram-positive bacterial pathogens are S. aureus, S intermedius, Clostridium, Enterococcus, Streptococcus, and other Staphylococcus spp. Methicillin-resistant S. aureus (MRSA) is rare but has been documented. Mycoplasma spp have been implicated in chronic sinusitis, often found in cockatiels. This organism is difficult to culture, and the true incidence is unknown. Staphylococcus and streptococcus (especially hemolytic strains) and Bacillus spp are thought to be responsible for several dermatologic conditions in psittacine birds. Staphylococci are often isolated from lesions of pododermatitis (bumblefoot) in many avian species.²⁶

Image 74. Streptococcus in a Gram’s stain; the red arrow is pointing to the orange-colored white blood cells, and the black arrow is pointing to streptococcus chains (image courtesy Kayleigh Griffin; used with permission).

“Clostridial organisms are common secondary invaders of damaged cloacal tissue in birds with cloacal prolapse or papillomatosis. Several specific syndromes of birds can arise from various species of clostridia. A Gram’s stain or anaerobic culture is necessary to identify these organisms. ²⁶

5.14.1 Diagnosis and Testing

“Diagnosis is based on clinical signs and results of cytologic examination and culture of tissue or swab samples. A Gram’s stain is used to identify normal flora, yeast, and spore-forming bacteria. Culture is needed to identify specific organisms and their sensitivity to antibiotics. Samples can be obtained from the respiratory, GI, urinary, and reproductive tracts. Sample sites for culture and cytology include the choanal slit, sinuses, cloaca, wounds, conjunctiva, internal organs (via ultrasound-guided, fine-needle aspirates, endoscopic examination, or surgery), and blood.” ²⁶

5.15 Bacterial Respiratory Disease

Bacterial respiratory disease is often a stress-related phenomenon resulting from a cold environment. It may also develop secondarily to an underlying Vitamin A deficiency.

The most common pathogens involved in psittacine bacterial respiratory diseases are:

• Klebsiella
• E. coli
• Enterobacter
• Pseudomonas
• Pasteurella
• Mycoplasma
• Salmonella
• Proteus
• Serratia
• Hemophilus
• Actinobacillus ³⁰

Image 75. Damage to the skin from mycoplasmosis (image courtesy Sofia Sangushko; used with permission)

5.15.1 Symptoms, Diagnosis, and Treatment

Clinical signs of bacterial respiratory disease may include sneezing, nasal discharge, dyspnea, lethargy, anorexia, exercise intolerance, wasting, and rarely, coughing. The clinical signs will vary according to the location of the infection, from the sinuses (upper respiratory), to the air sacs or the lungs. Tests used to diagnose bacterial respiratory disease are choanal

culture-and-sensitivity tests and radiographs. “Radiographs are extremely important in locating and characterizing the infection. ³⁰

Important differential diagnoses include:

• Viral respiratory diseases (Amazon tracheitis virus)
• Chlamydia
• Toxic inhalants (Teflon, smoke)
• Allergies
• Fungal disease
• Dyspnea caused by abdominal distention (non-respiratory cause).” ³⁰

Treatment involves the use of appropriate antibiotics (delivered by local application), systemic administration, and nebulization. Additional therapies include fluid therapy, Vitamin A therapy, and oxygen therapy if necessary. ³⁰

5.16 Spontaneous Bacterial Enteritis in Psittacines

Bacterial enteritis, including necrotic bacterial enteritis, is usually associated with stress, such as transportation, relocation, introduction of a new bird or person to the home, molting, breeding/egg-laying, and weaning. Sometimes the cause is unknown. ^{13, 20}

5.16.1 Symptoms

Clinical signs include diarrhea, dehydration, anorexia, weight loss, septicemia, and sudden death. The diagnosis is based on history, clinical signs, fecal gram stain, and cloacal culture-and-sensitivity. The fecal Gram’s stain will determine the number and type of gram-negative organisms in the feces. Other possible causes are poor diet, chlamydiosis, and hepatitis. Treatment for bacterial enteritis requires the use of appropriate antibiotics based on culture-and-sensitivity testing and fluid therapy. ²⁰

Image 76. Digitally-colorized scanning electron micrograph of Klebsiella bacteria (image courtesy Go Pets America), http://www.gopetsamerica.com/bio/bacteria/index.aspx

The most common pathogens involved in psittacine bacterial enteritis are:

• E. coli
• Klebsiella
• Salmonella
• Pasteurella
• Pseudomonas
• Aeromonas
• Citrobacter (caused by poor water hygiene)

Other, less common organisms include:

• Enterobacter
• Proteus
• Serratia
• Yersinia
• Mycobacterium
• Chlamydophila ^2O

Part VI Diagnostic Testing of Bacterial Samples

The two methods most used for identification of pathogens are Gram’s stains and cultures. Other methods are also used, but usually they are required after the sample has been tested by one or both of these methods and more information is needed about the pathogen. Today’s practitioners have at their disposal a wide variety of testing methods, from simple visual microscopic examination of impressions and unstained samples to state-of-the-art molecular diagnostic testing. These modern methods enable the clinician to identify and treat a wide range of pathogenic bacteria.

6.1 Observing the Bird for Illness

It is important that the owner pays close attention to the bird’s physical appearance so he may be able to detect early signs of bacterial or other pathogenic infections. There may be a change in the consistence of the bird’s droppings, loss of appetite, increased need for attention, increased sleeping, or other more subtle signs. If the owner waits until the bird is sitting on the bottom of the cage, he may find the is extremely ill and the situation is dire. If the owner observes any unusual signs, he needs to get the bird to the avian veterinarian immediately. He may do any number of tests, including Gram’s stains (oral and fecal smears studied under the microscope), blood samples to be sent to a lab for culture, and any other tests he deems necessary. ⁷

Ideally, the practitioner would wait for the results of the culture or other tests to come back from the lab, but when a bird is extremely ill, he must be treated with some medications right away, and test results often take a week or more. When the tests do come back, he may begin other treatments. The veterinarian may wish to do “antibiotic-sensitivity testing to determine the best antibiotic for that particular strain of bacteria present in the bird.” ⁷ The test results may mean a change to a more effective antibiotic.⁷

6.2 Brief Overview of Testing, Diagnosis, and Treatment

Diagnosis of bacterial disease is based on clinical signs and the results of cytology tests such as Gram’s stains and culture-and-sensitivity tests. Samples may be taken from the respiratory, GI, urinary, reproductive tracts, the choanal slit, sinus, cloaca, wounds, blood, conjunctiva, and internal organs (via ultrasound-guided, fine-needle aspirates, endoscopic examination, or surgery). ³⁴ A Gram stain is used to identify normal flora, yeast, and spore-forming bacteria. Culture is needed to identify specific organisms and their sensitivity to antibiotics. ^{26 34}

Antibiotics are chosen based on the results of Gram’s stains and culture tests. They should be delivered by mouth with an oral syringe since putting them in the drinking water is not a reliable method of delivery.³⁴ Antibiotics and other medications may also be delivered via nebulization directly into a bird’s respiratory tract; this is particularly useful in cases of respiratory diseases. ⁵⁰

Most bacterial infections are contagious from bird-to-bird by the droppings and water, but only a few are zoonotic to humans. ³⁴

6.3 The Gram’s Stain Diagnostic Test

The Gram’s stain is an easy-to-use diagnostic test that has long been used in avian medicine to look for pathogens. It is quick, easy, convenient, and affordable to most clients. When combined with the physical examination and a good knowledge of avian medicine, this test is helpful in identifying early stages of many diseases. With it, the clinician is able to identify a particular pathogen or disease process before clinical signs occur. It may be used along with other clinical data gleaned from the bird’s history, the physical examination, cytological stains, cultures, and PCR tests. ¹⁵

6.3.1 Hans Christian Gram

The Gram’s stain method is named after its inventor, the Danish scientist, Hans Christian Gram (1853–1938), who developed the technique in Berlin in 1884. Gram devised his technique, not for the purpose of distinguishing one type of bacterium from another, but to make bacteria more visible in stained sections of lung tissue in humans. ⁴¹

Image 77. Hans Christian Gram, developer of the Gram’s stain (image courtesy Wikipedia: Hans Christian Gram) https://en.wikipedia.org/wiki/Gram_staining

6.3.2 The Gram’s Stain’s Function$

Gram’s staining is used to determine the presence of pathogenic bacteria in terms of their reaction to the Gram’s stain. They will be either Gram-positive and Gram-negative. The differences in staining occur due to variations in the cell-wall structures that bind the stains differently. This test is used to distinguished whether the bacteria present under the microscope are pathogens or normal, resident, beneficial bacteria. This varies among species, and interpretation requires considerable experience.¹⁰

6.3.3 Body Locations of Samples Taken for Gram’s stains

Normally, the stain is performed on samples from the gastrointestinal tract—from the choana, oral cavity, cloaca, and feces. This test is recommended for both healthy and sick birds at their annual exams. Any abnormalities warrant further diagnostic testing, including cultures and PCR tests. Other samples that may be tested with the Gram’s stain are of upper respiratory tissue, including the nares, oral cavity, sinus cavity, choanal lesions and naso-ocular discharge. Lower respiratory samples may be collected from air-sac fluids and swabs collected by endoscopic exam.¹⁵

Image 78. Gram’s staining is a method of differentiating bacterial species into two large groups: Gram-negative (red stain) and Gram-positive (blue/purple stain) (image courtesy 123rf)

Most abnormal bacteria enter through the oral cavity. Bloody mucosa or excessive mucus are reasons to perform the cytological test. The oral cavity, including the commissure (corners of the mouth) and undersides of the tongue, should be swabbed for samples and may reveal important information when tested. The gastrointestinal tract may be sampled in several different places. The oral cavity and crop may be swabbed, along with resulting fluid derived from it, and the cloaca may be swabbed to obtain fecal material. Fresh fecal samples from droppings may also be utilized. Crop, oral cavity, and cloacal swabs need to be collected carefully so that the highly vascular and friable (flaky and dry) tissues are not irritated, which can lead to bleeding. ¹⁵

Fecal samples may be viewed directly before they are stained. Motile bacteria, bacterial density, parasitic ova and cysts, urates, and undigested material are all able to be identified. With granulomas (a mass or nodule of inflamed or infected tissue) and skin lesions, the tissue under the wounds can be sampled and stained. Other areas that can be tested and analyzed are the feather pulp (inside of a blood feather) and feather follicles. ¹⁵

Image 79. This picture is showing a negative gram stain test and a positive Gram’s stain test. A Gram’s stain test is performed by putting alcohol on the bacteria. It will either turn a violet color or a pink red color. If it’s violet, the test is positive; if it’s a red-pink color, the test is negative. A positive result means the bacteria will have a thick cell wall, a negative result that means the bacteria has a thinner cell wall. Pseudomonas fluorescens will be negative if a Gram’s stain test is performed (image courtesy SA Site for Science).

6.3.4 Further Testing Determined by the Results of the Gram’s Stain

One benefit of the Gram’s stain is to prompt the clinician to pursue other diagnostic assays if he is not satisfied with the results of the Gram’s stain.¹⁵ For example, if inflammatory cells, abnormal red blood cells, or other abnormal cells are suspected from the Gram’s stain, the practitioner will want to perform another cytological stain or possibly a culture-and-sensitivity test. Further tests may include a Polymerase Chain Reaction (PCR), a molecular diagnostic test. ¹⁵

Image 80. Gram’s Staining. A Gram’s stain of mixed Staphylococcus aureus (S. aureus, Gram-positive cocci, in purple) and Escherichia coli (E. coli, Gram-negative bacilli, in red), the most common Gram-stain-reference bacteria (image courtesy Wikipedia). https://en.wikipedia.org/wiki/Gram_staining)

6.3.5 What information does the practitioner glean from the Gram’s stain that cultures cannot provide?

“Cultures alone cannot identify many important aspects in a sample that the Gram’s stain may reveal. The culture cannot identify:

• Numbers of yeast, fungal hyphae, and budding yeast
• Sporulated rods, spirochetes, megabacteria (Macrorhabdus ornithogaster, a fungus), protozoa, and the relative number and percentages of bacteria
• Pathogenic bacteria which have special growth requirements, e.g., Pasturella species.” ¹⁵

6.3.6 Gram-negative Smears

If the bacterial population fails to take up the blue-purple part of the Gram’s stain, it will only retain the red counterstain and therefore appear red or Gram-negative. Gram-negative organisms are more likely to be pathogenic in birds, but not always.10Brown

Image 81. This Gram-negative smear (1000x magnificaion) was taken from a cultured sample of a sinus swab in a cockatiel with sinusitis (sinus infection) and shows both characteristic red Gram-negative bacilli (rod shaped) and cocci (round) bacterial organisms (image courtesy D. Brown). ¹⁰

6.3.7 Gram-positive Smears

Bacteria can be identified as being pathogenic based on their staining characteristics by using a Gram’s stain. Since these bacteria have taken up the blue-purple part of the stain, they are Gram-positive. Most Gram-positive organisms are beneficial and normal in most parrots, but some cause disease. ¹⁰

Image 82. This is a Gram-positive smear at 1000x magnification. It was taken from a cultured sample of a routine sinus swab in a cockatiel and shows both characteristic blue-purple, Gram-positive bacilli (rod-shaped) and cocci (round) bacterial organisms (image courtesy D. Brown).10

6.3.8 Images of Various Bacteria after Gram’s staining

6.3.8.1 Appearance of Mycobacterium organism. Some Gram-positive bacteria can be pathogenic, such as the Mycobacterium organism, a rod-shaped bacterium.

Image 83. This image shows liver tissue with avian tuberculosis bacterial organisms, specifically Mycobacterium spp (a Gram-positive, aerobic bacteria, occurring as slightly curved or straight rods.) The sample has been stained red-purple and viewed at 400x magnification. It is from a long-tailed finch (image courtesy D. Brown)10 Brown

6.3.8.2 Appearance of the Spiral and Spirillum Bacterium

Image 84. Spirillum bacteria, a variation of the spiral bacteria as it appears in a Gram’s stain. They have a corkscrew appearance (image courtesy Imarcade).

Imarcade.com http://imgarcade.com/spirillum-bacteria-under-microscope.html)

6.3.8.3 Appearance of the Coccus Bacterium

Image 85. Cocci, or round-shaped bacteria in a Gram’s stain (image courtesy Imarcade). http://imgarcade.com/coccus-bacteria-under-microscope.html

6.3.8.4 Appearance of Cocci in a Gram’s Stain.

In Some Cocci Infections, the Bacteria Form Chains

Image 86. Streptococcus pneumoniae, a Gram-positive bacterium (image courtesy Imarcade). http://imgarcade.com/cocci-bacteria-under-microscope.html

6.3.8.5 Appearance of Rod-shaped Bacteria

Image 87. Rod-shaped Bacteria. Colored scanning electron micrograph (SEM) of rod-shaped (bacillus) bacteria. The tubes connecting the bacteria are pili, which are used to transfer genetic material between bacteria in a process known as conjunction (Image courtesy Science Photo Library)

6.3.9 The Gram’s Stain Method of Bacteria Identification

The Gram’s stain is a test used to identify bacteria by the composition of their cell walls. Oral and fecal samples are put through a staining process after which the practitioner looks for the distribution of various bacteria. Bacteria are first stained with a purple dye called “crystal violet” which specifically binds to peptidoglycan, a complex structure of amino acids and sugars found in the cell wall. This is followed by a series of steps that ultimately removes any unbound or loosely bound crystal violet.  ^{51, 54.}

Then the cells are stained with a second red-colored dye called safranin. Gram-positive bacteria stain purple because their cell walls are rich in peptidoglycan. Gram-negative bacteria, whose cells walls have two layers, take on a red coloring. The outer layer of lipids does not bind strongly to crystal violet, and the dye is easily washed away during the staining process. For example, Streptococcus pneumoniae, which causes pneumonia, is a Gram-positive bacterium, while  E.coli and Vibrio cholerae (which causes cholera), are Gram-negative bacteria. ¹¹

Sometimes, while the clinician is performing the Gram’s-staining technique, there will be errors in the process, making interpretation difficult. The slide may be overheated, or the sample may be decolorized; these are the most commonly found errors. The technique must be uniform, and fresh samples must be used.¹⁵

Certain factors influence the interpretation and effectiveness of the Gram’s stain:

• Age and species of the bird
• Diet
• Cage hygiene
• Husbandry practices. ¹⁵

6.3.10 Discerning Normal from Abnormal Bacteria in a Gram’s stain.

Clinicians need to be able to judge normal from abnormal bacteria and know the number and ratios of normal bacteria for a particular species. Normal oral and GI flora from psittacine birds consist primarily of Gram-positive rods and cocci. An occasional Gram-negative rod or fungal organism (yeast) is normal, but if there is an abundance of these, or they are frequently seen in successive stains, they are considered abnormal. ¹⁵

Normally, the choanal slit (narrow opening in the top of the mouth) of birds contains squamous epithelial cells and a slight-to-moderate number of bacteria. They usually stain Gram-positive. Abnormal stains may contain inflammatory cells, yeasts, fungal hyphae (long, branching filamentous structures of a fungus), or a large number of Gram-negative rods or cocci. ¹⁵

“Epithelial cells form the epithelium, which is a membranous tissue that covers the internal area of organs and other internal surfaces of the body and also covers the external skin. If the stained sample contains few epithelial cells and fewer-than-normal numbers of bacteria, that is a cause for concern. Ideally, there should be no more than 10% of Gram-negative bacteria in psittacines. An increase of more than 10% of Gram-negative bacteria is not normal. The more Gram-negative bacteria found, the more pathogenic the situation. Just because there are no Gram-negative bacteria in a sample does not mean they are not present elsewhere in the area of the body from which the sample was taken. Any abnormal findings are cause for additional testing, such as culture-and-sensitivity tests and a complete blood count (CBC), especially the white-blood-cell count (WBC).” ¹⁵

Once he gets the results of the Gram’s stain back, the practitioner will record the results of the test.

Blood tests can be used to check for serum antibody levels to certain organisms, including bacteria. PCR can also be used but is generally run on tissue swabs, not blood. Bacteria in the blood indicates sepsis. About 50% of septic cases die.

The feather pulp and skin swabs are performed to check to see what kinds of organisms are present in that area. They may or may not represent the cause of a skin or feather pulp problem. R. Dahlhausen

6.3.11 Diagnosing from the Gram’s Stain

Gram’s stains provide valuable information to the clinician; however, they do not constitute a diagnosis; neither can they assist in the diagnosis of other difficulties the bird may have, such as a respiratory problem or injury. ¹⁸

Diagnosis depends on other screenings in addition to the Gram’s stain. The Gram’s stain is a valuable diagnostic screening test in both well and sick birds, but other factors need to be taken into consideration, such as the bird’s history and the results of the culture and CBC tests.¹⁵

The bird owner needs to pay close attention to the bird’s physical appearance. If the bird shows signs of illness, the owner needs to make an appointment with the veterinarian and have these tests performed. It takes a while for the results to come in many instances; meanwhile, as the clinician and owner wait, the bird continues to become more and more ill. Before he even knows the information gleaned from the tests, he must prescribe medication to treat the symptoms at that time, based on his differential diagnoses (possible reasons for illness). He may prescribe a broad-spectrum antibiotic that will aid in recovery until he is able to do sensitivity testing and prescribe the correct antibiotic for the illness.

6.3.12 Interpretation of Gram’s Stain Results

Interpretation of what is visible on the Gram’s stains is not easy; it takes experience to sort through all that is there and find the pathogen responsible for the bird’s illness. Many other areas must be explored as well; the bird’s history and symptoms are of great importance. The following images and their explanations are examples of documentation of the results of the Gram’s stains.

KEY: Hx = History, CS = Clinical Signs, GS = Gram’s stain results Rx = Therapy

I

Image 88. Four-year-old male Budgerigar, Apparently healthy bird, fed a pelleted diet. CS = none. Gram Stain results = Normal distribution of organisms: 157 total bacteria per field, 70% gram-positive rods, 30% gram-positive cocci, 0 gram-negative bacteria, 0 yeast. Digestion of food is complete (image courtesy Clinical Avian Medicine, Harrison-Lightfoot).

Image 89. African grey parrot, 4 years old, sex unknown: Hx = Intermittent vomiting or loose stool, not as playful. GS = 400 bacteria per oil field, 95% Gram-positive short rods, 5% Gram-positive rods, 0 yeast. Overgrowth of intestinal bacteria, enterotoxaemia (a condition induced by the absorption of large volumes of toxins produced by Clostridium perfringens from the intestines), malnutrition. Rx = Aggressive (image courtesy Clinical Avian Medicine, Harrison-Lightfoot).

Image 90. Severe macaw, 7 years old, sex unknown: Hx = Depressed, not eating, weak. CS = underweight, scant feces, dark yellow urine and urates, malcolored feathers. GS = 200 bacteria per field, 1% gram-positive rods, 0% gram-positive cocci, 98% gram-negative rods. Rx = Aggressive (image courtesy Clinical Avian Medicine, Harrison-Lightfoot).

Image 91. Umbrella cockatoo, 6-year-old female: Hx = Exposure to carnivorous pets, seed only diet. CS = Fetid stool, weight loss, passing undigested food. GS = 200 bacteria per field, 10% gram-positive rods, 90% gram-negative rods, of which 50% are Clostridium sp. Rx = Aggressive (image courtesy Clinical Avian Medicine, Harrison-Lightfoot).

Cultures are done along with the analysis of growth on certain media plates and certain biochemical tests and morphology to identify the bacteria involved. The organism can be grown on a special media plate with multiple discs, each containing a certain antibiotic. This is the sensitivity part of the test. The Zone of Inhibition of growth around the disc determines if the organism is sensitive or not to that antibiotic.

Bob Dahlhausen

Sensitivity testing

Image 92. Moluccan cockatoo, 7-year-old male: CS = smelly stool. GS = 50 bacteria per field, 90% gram-positive rods, 10% gram-positive cocci, 30 Clostridium sp. organisms. Rx = Aggressive (image courtesy Clinical Avian Medicine, Harrison-Lightfoot).

Image 93. “Zone of Inhibition” assay on a culture plate to define which antibiotic works the best. The size of the zone is relative to the potency of the antibiotic. The “Zone of Inhibition” means that the bactericidal or bacteriostatic agent has either inhibited or killed the organisms that were spread on the plate, and that those organisms are susceptible to that agent

(image courtesy Toxikon Services). http://www.toxikon.be/services/Microbiology_Pharma_Biotech.cfm)

6.4 Other Stains Used in the Diagnostic Process

These are the routine stains used in avian cytology, histopathology, and histology. Each of these stains is used for a particular purpose, depending on what the bird is being tested for.

• Wright’s stain
• Wright-Giemsa stain
• Giemsa Stains
• Quick or Stat Stains
• New Methylene blue stain
• Special stains
• Acid-fast stain
• Gram’s stain
• Macchiavello’s stain
• Modified Gimenez stain
• Natt and Herrick’s solution
• Sudan III and Sudan IV stains

“Most of these stains have been in use for many years. The cytology and histopathology stains for birds are going to be the same as for animals and people. The same is true for hematology. Wright-Giemsa stain or a Quick or Stat stain like Dif-Qwik are most commonly used in the clinic setting. Most of the others are special stains and are used by laboratories for special purposes. New Methylene Blue stain is used in cytology and histopathology, typically for staining immature red blood cells. ¹⁵

“Hematologic stains. There are a number of special stains employed to identify specific inflammatory cells seen in peripheral blood and tissues. These include the all-purpose Wright-Giemas and Giemsa stains, leukocyte alkaline phosphatase (LAP), tartrate-resistant acid phosphatase (TRAP), and myeloperoxidase (MPO). ¹⁵

“There are a variety of “Romanowsky-type” stains with mixtures of methylene blue, azure, and eosin compounds. Among these are the giemsa stain and the Wright’s stain (or Wright-Giemsa stain). The latter is utilized to stain peripheral blood smears. The giemsa stain can be helpful for identifying components in a variety of tissues.¹⁵

“One property of methylene blue and toluidine blue dyes is metachromasia. This means that a tissue component stains a different color than the dye itself. For example, mast cell granules, cartilage, mucin, and amyloid will stain purple and not blue, which is helpful in identifying these components. ¹⁵

“Fat Stains: Lipids cannot be demonstrated in routine tissue sections, as during processing the tissue and clearing, lipids will be dissolved. Lipids are routinely demonstrated in frozen sections or cryostat sections. ¹⁵

“Special fat stains used are:

• Oil Red O
• Sudan III
• Sudan IV
• Sudan Black
• Osmium tetroxide

“For more information on stains, the reader may research the individual stain on Wikipedia. There are sites which contain specifics about the individual stains.

“Other sites which offer information about stains are::

• https://webpath.med.utah.edu/HISTHTML/STAINS/STAINS.html
• https://www.histopathology.guru/?s=stains”

(All information on stains from Bob Dahlhausen, personal communication.)

6.5 Culture-and-Sensitivity Diagnostic Testing

A culture refers to the propagation of living organisms or the living tissue cells in special media conducive to their growth. It is also the product of such propagation. It is used when birds are suspected of having a bacterial infection and the Gram’s stain does not yield sufficient information. ⁸

6.5.1 Culture-and-Sensitivity Testing Methodology

To perform the test, a sterile swab of the body fluid in question is obtained and streaked on a laboratory plate. These samples can be from sinus drainage, fecal and oral material, or pus. The plate is a shallow, flat receptacle filled with agar; this provides the nourishment that allows the suspected bacteria to grow. The culture plate is then placed in an incubator overnight. By the next day, bacterial growth is usually visible. If insufficient growth has occurred, the organism may be placed onto a different growth medium and incubated for another twenty-four-hour period. This way, the culture process allows the specific bacteria infecting the bird to be identified. ²⁵

Once the pathogenic organism has been identified, the clinician will perform sensitivity testing to determine the sample’s response to different antibiotics. “Sensitivity” refers to the ability of the one or more of the antibiotics to kill the bacterium. If the bacterium is killed by the antibiotic, it is “sensitive” to it.²⁵

“To test for sensitivity, antibiotic-impregnated paper discs are placed on the surface of the culture plate on which the bacteria are growing. After a period of time, the plates are observed for bacterial ‘kill off.’ This is manifested by a clear zone (Zone of Inhibition) around one or more the antibiotic discs, indicating that the bacteria are unable to live and grow in the presence of that particular antibiotic.” ²⁵

Not all bacteria are killed by all antibiotics. The veterinarian will choose the most effective antibiotic for the bird’s infection, based on the results of the culture-and-sensitivity testing. ²⁵

Image 94. Bacterial growth on a petri dish (image courtesy https://uk.vwr.com/store/content/externalContentPage.jsp?path=/uk.vwr.com/en_GB/microbiology_segment.jsp).

Image 95. Colony of bacteria in culture medium plate (image courtesy 123rf). https://www.123rf.com/stock-photo/bacteria_culture.html

Image 96. Agar as a medium for bacterial growth

(image courtesy Just We Diminute). http://www.justwedeminute.com/2010/04/ewww-growing-bacteria-for-science.html)

6.5.2 Commonly Found Bacteria in Cultures

Normal fecal bacteria cultured from healthy birds include:

• Gram-positive bacilli (Lactobacillus spp., Bacillus spp., Corynebacterium spp., and Streptomyces) Older birds tend to have more Corynebacterium and less Lactobacillus than juvenile birds.
• Gram-positive cocci (Staphylococcus epidermidis, Streptococcus spp., Aerococcus spp., and Micrococcus spp.)
• Escherichia coli is commonly recovered from cockatoos, but less commonly in other species.
• Gram-negative bacteria occasionally found in clinically normal birds include: Enterobacter, Klebsiella, Citrobacter, Pasteurella, and Moraxella spp.
• While some Pseudomonas spp. have been recovered from healthy birds, P. aeruginosa is rarely found in healthy birds.
• Isolation of Proteus, Salmonella, Pseudomonas, Klebsiella, Listeria, Erysipelothrix, and hemolytic Staphylococcus aureus is clinically significant in sick birds.”

Cultures from other sites such as the eyes, ears, and choana usually show similar results. Any heavy overgrowth of bacteria warrants further investigation.” ¹⁸

6.6 Identifying the Pathogens Using Cytology and Histopathology

There are some differences between cytology and histopathology. “Cytology is done with a swab or fluid from a fine-needle aspirate (FNA).  It does not contain solid tissue, so it cannot assess tissue architecture, just cell types present.  Histopathology is tissue collected by biopsy or necropsy.   For example, a crop swab or crop wash yields cytology and culture samples but cannot evaluate the health of the crop tissue.  Histopathology of the crop evaluates the crop wall itself.  Histopathology is not used for culture as it is placed in formaldehyde (Formalin), but one can culture the sample before placing it in Formalin.  Both can see bacteria and cells. Cytology images consist of the whole organism spread out across a slide, while histopathology uses cut samples, usually tissue blocks, so they will look a little different.  Histopathology is not always of disease samples, but it is some form of tissue, so any bacteria may be embedded in it (typically).   The results will also depend on which stain is used.” (Bart Huber, personal communication; used with permission).  

6.6.1 Cytology

Cytology is the study of the structure, function and chemistry of cells. It deals directly with the structural and functional organization of cells and also with metabolism, ontogenetic differentiation (the development of an individual organism from inception to maturity and comparing it to that of another organism), heredity, and phylogeny (the evolutionary history of an organism). ²⁰

Cytology is the study of cellular anatomy, physiology, pathology, and chemistry, and it provides valuable information about the disease process being examined. Only a very small sampling of cells is required so it doesn’t further traumatize the already-compromised tissue. ⁸

Cytological tests can be used to identify cancer cells, the sex of birds, and to give information on the nature of infectious processes, particularly whether they are acute or chronic. Cells from any part of the body may be examined, e.g., the digestive and respiratory tracts, oral and fecal areas, skin, and joints. ⁸

Image 97. Cytology of normal bacterial microflora in a cloacal sample from a Yellow-fronted Amazon parrot using Gram’s stain (image courtesy Terry Campbell: Avian Hematology and Cytology. Iowa State Univ. Press, 1988, p. 50).

Image 98. Chronic active sinusitis in a Scarlet-chested Parrot. Small, round purple intracytoplasmic inclusions (center) are seen in many of the cells. A presumptive diagnosis of chlamydiosis was made based on these findings and the clinical signs. Chlamydiae were isolated from the sample. The sample was stained with Diff Quick (image courtesy Terry Campbell: Avian Hematology and Cytology. Iowa State Univ. Press, 1988, p. 50).

6.6.2 Histopathology

Histopathology is the microscopic examination of tissue changes caused by disease. It refers to the examination of a biopsy or surgical specimen by a pathologist after the specimen has been processed and histological sections have been placed onto glass slides.. ^{3, 21}

Many diseases cannot be identified by simple light microscopy of organ contents. They may require histopathology. This is a process by which very fine sections of suspect tissue are sliced, stained, and prepared for examination. They may be stained and examined immediately; other times, they may need to be cultured before they can be stained and examined. Gram’s stains are usually performed first, then, if necessary, other methods of testing may be utilized. ⁹

6.6.3 Methods of Obtaining Cell Samples for Cytology and Histopathology:

• Swab: In an exposed area of the body, such as an open wound, a swab or scraping of the area will be taken and its contents spread on a slide. ⁸
• Impression smears, also called “contact smears” from skin and internal organs. The slide will be pressed directly onto the affected area to obtain the needed cells. ⁸
• Fine-needle aspirate of masses or organs: If a sample is needed from an internal area of the body (e.g., fluid in the abdomen), a sterile needle and syringe will be utilized to remove the necessary sample. ⁹
• Saline wash: “If samples are needed from the crop, air-sac, or trachea, sterile saline will be instilled into these areas and then removed by sterile syringe and tubing. The saline solution will then contain numbers of cells that can be examined.” ^{4, 7}
• Sinus aspirates, often performed with saline washes. ⁷
• Abdominocentesis: introduction of a needle into the abdominal cavity in order to reach fluid. ⁷
• Arthrocentesis: using a syringe to collect synovial fluid from a joint capsule. It is also known as joint aspiration ⁷
• Scrapings from the palpebral conjunctiva or cornea of the eyes, from the oral cavity, or tissues that normally yield poor cellular samples. ⁷

6.7 Other Testing Methods

Many types of tests will indicate the presence of bacteria. Lab tests for avian species are divided into several basic groups:

• Indicators of immune system activity: the CBC and EPH (electrophoresis: A method of separating substances, especially proteins, and analyzing molecular structure based on the rate of movement of each component while under the influence of an electric field.) ⁴²
• Serum biochemistries (blood tests): indicate the condition or function of various organ systems.
• Serology (Gram’s stains and cultures): tests for antibodies to various diseases. Antibodies are small proteins that circulate in the bloodstream. They are part of the body’s immune system and are made by B lymphocyte while blood cells. Antibodies attach to proteins and other foreign chemicals in the body which they recognize as abnormal. The foreign proteins and chemicals that antibodies attach to are called “antigens.” ⁴²
• Antigen-detection tests: tests for the antigens specific to infectious agents. Some tests can identify the antigen on the surface of some bacteria. ²⁵
• Miscellaneous: randomly utilized tests such as urinalysis. ²⁵

Conclusion

The devastating effects of bacterial diseases on avian populations are enormous. As science continues to explore and understand the number and function of current bacterial pathogens, newly discovered bacteria await analysis and description. Bacteria that are harmful to birds, both pet and wild, are unable to be identified without cytology and histopathology to define them.

Care must be taken by owners to keep the aviaries scrupulously clean, watch for signs of infection, and obtain proper diagnoses and treatments from avian veterinarians as soon as possible. Therapeutics provide the optimum chance of eliminating the disease if it is caught early. Bacteria travel and reproduce quickly, so there is no time to waste. Constant observation of the bird and his environment is of utmost importance.

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Appendix A, from p. 31

Staph vs MRSA – What’s the Difference?

Staph vs MRSA – What’s the Difference? (staph-infection-resources.com) Image courtesy Staph Infection Resources

The differences between MRSA versus S. aureus are significant when it comes to antibiotics and infection control. The key differences listed below play a big role in treatment effectiveness and how quickly a person recovers. In many other ways, however, the differences can be minimal between these two infections.

How they are alike

• The symptoms of MRSA vs S. aureus are very similar. MRSA can be more virulent and more invasive than S. aureus. The rare and deadly form of these infections, called “flesh eating disease” (necrotizing fasciitis,) is more commonly caused by MRSA rather than S. aureus.
• In photos, MRSA and S. aureus look nearly identical. Because they look so alike, the best way to tell them apart is to get tested.
• Both of these infections are also contagious and can easily spread from person-to-person or from contaminated surfaces.
• The most effectively used alternative remedies can work equally well for both S. aureus and MRSA. The lack of resistance issues with most natural and alternative therapies is one of their big benefits.
• MRSA and S. aureus are the same species of bacteria. MRSA (short for Methicillin Resistant Staphylococcus Aureus) is just a special kind of Staph (short for Staphylococcus aureus, or more commonly Staph aureus). The main differences between the two are listed below.

Key differences

• The big difference between S. aureus and MRSA is with antibiotic treatments. MRSA is resistant to most commonly used drugs, but S. aureus is much less resistant. This is an important difference when it comes to choosing the right antibiotic for an infection. MRSA also tends to result in longer, more expensive hospital stays than S. aureus.
• S. aureus is more common than MRSA. Around a third of the people in the U.S. are carriers of S. aureus bacteria on their skin, while fewer than 5% carry MRSA. S. aureus bacteria are extant and a natural part of the environment. Thankfully, MRSA is still mostly confined to hospitals and healthcare environments, but it has been growing rapidly in the community over the last decade or so.
• MRSA can be harder to kill on surfaces than S. aureus. For some disinfectants, such as silver-based products, the kill time for MRSA can be two or three times the kill time for S. aureus.

S. aureus as MRSA (image courtesy CDC) https://www.cdc.gov/mrsa/community/photos/photo-mrsa-1.html).

Appendix B: from p. 34

Case Study: Author’s rescued cockatiel, Boots. Severe sinus and eye bacterial infection.

The attending veterinarian is Dr. Bob Dahlhausen.

May 25, 2021. The bird arrived at the author’s home. Weight: 100 g. There was a heavy scab over the right eye, pushing skin and bone out, away from the eye. I removed the scab and blood and other fluids emerged from the eye. The next day I took him to the avian veterinarian. He had had sinusitis for a long period of time, and this led to the globe collapsing and the lens beginning to calcify. Dr. Dahlhausen injected an antibiotic directly into the bulbar conjunctiva under the globe. The antibodies had infused deposits in the lens.

Severe sinus infection in the author’s cockatiel. The bacteria was Streptococcus aureus. The image was taken after the scab was removed; the orbit had collapsed, and the eye had sunk down under the skin. For several days, the tissue leaked blood and fluid. The scab had pushed the skin and feathers away from the eye in a circular manner, and a hard ring of the forced tissue remains (see black arrow) (image courtesy J. Miesle).

Severe sinus infection in a cockatiel. This is a bird with a similar condition. The scab is still on this bird’s eye, and it gives you an idea of what the author’s bird looked like when she took him in (image courtesy Melbourne Bird Vet; used with permission).

He was to be kept separated until the results of chlamydia test came back. Everything in the respiratory tract was inflamed, and there was undigested fiber in the stool. Gram’s stains showed pus and gram-positive bacteria. The eye could not be removed because the optic nerve is short, and any pressure or tension would kill the bird. He would manage it medically. Boots has no vision in the eye. I was to put warm compresses on it to sooth it and prevent a recurrence of it scabbing over. I was also to put drops of saline solution in the eye 3-4 times a day for at least 2 weeks, probably much longer, to prevent the eye from closing up. If that happened, the infection could start up again since the fluid would not be able to drain. He also gave me an antibiotic cream to put on the eye daily. Boots was started on Azithromycin and that continued for several weeks. His weight was 100 g. when he was taken in. I had begun giving him Emeraid Nutritional Supplement, both Omnivore and Carnivore, plus vitamins, several times a day from the first day on. He continues to receive this to the present day and it will continue indefinitely. His left eye has a large cataract on it, preventing sight. He is, for the most part, blind.

The chlamydia test was negative. By the 31^st, his weight had plummeted to 80 grams and he was losing more each day. He had no appetite.

June 4: Boots’ weight was down to 73 g. We made an emergency visit to Dr. Dahlhausen at 8 a.m. He gave Boots two injections: Robenacoxib and Doxycycline. He said they would begin to work in a few hours. He also said there’s a pocket of pus in the right eye which is causing the infection to remain.

Ball of pus in the conjunctiva (image courtesy J. Miesle).

I’m to put the antibiotic cream he gave me into it four times a day and to continue giving the Emeraid mixture as often as possible. It’s touch and go now to see if we can turn this infection around. I continued to put either thin mashed potato or dampened Rice Krispies in his beak and syringe the Emeraid Omnivore and Carnivore with vitamins mix into the mouth to help it go down. I give him the Emeraid every 2 hours and the food every 2-3 hours, and I get him up every night around 12 to do this again.

June 7: His appetite has improved and he is up to 78 g. He received more azithromycin from Dr. Dahlhausen and another tube of ophthalmic antibiotic ointment for his eye.

June 14: Every attempt to save his life is being made. We returned to the doctor. The left eye with the cataract is not as red, and the oral tissues are also not as red. He can see a little out of it; I suspect he sees light, and is seeing a little out of the peripheral vision. The ocular bulb will eventually coalesce down till there’s nothing left. The little ball of pus and bacteria is under the bulbar conjunctive tissue, so there will always be something there. Hopefully, it will eventually be absorbed by the body. The doctor just wants to be sure it doesn’t start up the infection once we finish the Azithromycin. He will be on the Azithromycin for 3-8 more weeks. I am to watch the redness in his oral cavity and eyes daily. They seem to be clearing up. He gave me more Azithromycin, and I’m to bring him in every week for the next 3 weeks.

June 21. In for another checkup and more Azithromycin.

June 28. In for another injection of Robenacoxib and Doxycycline

July 6. In for checkup. More eye ointment and another doxy injection. Weight: 89 g. He is stable and continues to eat well. The eye is looking much better.

July 22. The eye is less red and watery. I’m to keep it from closing up by using the antibiotic drops and ointment.

Aug 19. I am to continue putting antibiotic drops and/or eye antibiotic cream into the eye daily. Weight is stable at 89. He is enjoying his food and finding his way around the areas in which he was placed. He can see a little out of the left eye. The circular ridge around the eye is permanent; it is result of the scab pushing the skin away from the eye and impaling the skin.

Oct 22. The eye continues to be in the same condition; however, the tissue in and around the orbit tends to get red when touched. It is extremely thin and fragile. This past week I have noticed very tiny pieces of matter coming out of the orbital area. I remove them with a Q-tip and I notice some moisture coming with them; this makes me sure they are coming out of the orbit. I am continuing to put the sterile drops and ointment on the eye. I believe that little ball of pus in the orbit is breaking down as it appears to be getting smaller. Tiny feathers are beginning to grow on the skin around the circular area.

Nov. 3. Boots’ feather coat is very heavy, and he is beginning to preen more than he had. He is flapping his wings when held out a little better than before. He still doesn’t seem to know how to do this, but we keep working on it. He seems to be seeing a little more than he had with his good eye.

Bird owners should realize that using products with Teflon coating should not be used around birds. Other brand names with polytetraflouethylene non-stick coating are Silverstone, Fluron, Supra, Excalibur, Greblon, Xylon, Duracote, Resistal, Autograph and T-Fal. Some time ago, the San Antonio Zoo in Texas lost 21 birds in an outdoor aviary.

Their death was attributed to recently installed lights in an outdoor aviary. The bulbs had been coated with Polytetraflouethylene (PTFE). PTFE can also be found on cooking and baking utensils, electric cookers, portable heaters, irons with nonstick plates, self-cleaning ovens, some hair dryers and curling irons – to name a few. Ask the manufacturer if uncertain.

Self-cleaning ovens: Do not run the self-cleaning cycle on ovens when birds are around. Self-cleaning ovens are lined with PTFE (Teflon) and reach 900 degrees Fahrenheit during the self-cleaning cycle and emit gasses into the air that kill birds rather quickly.

Slow cookers that has a metal interior often have a non-stick (Teflon) coating. Better choices are stockpots made of ceramic, stainless steel, or other safe metal.

Aluminum Foil with Non-stick Coating: A new type of Aluminum Foil made by Renolds Wrap (also known as “quick release style”) has caused the death of some parrots. Pet owners, who may very well be aware of the dangers that cooking with non-stick pans can pose, are oblivious to the fact that any items with non-stick coating pose the same dangers. One person who did some baking with such nonstick-coated aluminum foil lost her pet birds shortly afterwards because of toxic off-gassing.

Stain-resistant Coating: PTFE coating can also be found on clothing and material (with “stain-resistant coating”). Carpet cleaning companies will try to sell you on “stain protection” coating — also PTFE!

Shatter Resistant or Safety-coated Light Bulbs are a potential source for toxic fumes that can be dangerous to birds. These bulbs have or may have a coating made of polytetrafluoroethylene (PTFE) which makes them shatter resistant. A veterinarian researched the death of a customer’s birds and found out that the coating heated up during the use of the bulb, and in the enclosed coop produced high enough concentrations of toxic fumes to kill the chickens.


DuPont Fined for Teflon Cover-Up : The Environmental Protection Agency (EPA) announced it will fine Teflon maker DuPont $16.5 million for two decades’ worth of covering up studies that showed it was polluting drinking water and newborn babies with an indestructible chemical. It was EWG’s petition that sparked EPA’s lawsuit against DuPont. The fine is the largest administrative fine the EPA has ever levied under a weak toxic chemical law. However, the $16.5 million fine is less than half of one percent of DuPont’s profits from Teflon from this time period, and a fraction of the $313 million the agency could have imposed. Yet another reason to strengthen our toxic chemical laws, which EWG is launching a campaign to do. Ref: http://www.ewg.org/research/poisoned-legacy

Safer Alternatives:

• GreenPan cookware utilizes a “100% PTFE-free non-stick technology called Thermalon, a surfacing that not only allows for flawless oil-free cooking, but is also completely free from the toxins that other non-stick cookware can release into your food and your home.”Cuisinart GreenGourmet Ceramic type pans Stainless Steel Scanpan : Available over the Internet or in better kitchen stores. Some questions were raised if this cookware was indeed ” PTFE-free.” Indeed, they do use Greblon for their cookware – a non-stock coating that can pose a danger to birds. A communication with them on this topic yielded the following response:
  • ” Scanpan is free of PFOA, but does use small quantities of PTFE based substance … however … the fumes from cooking margarine are as toxic or more toxic than a melting frypan. Only a pan that is totally melting due to being left on the range at 600 to 800 degrees without food to pass the heat to will cause the fumes that you are concerned with.”

Pet owners share their experiences with Teflon Poisoning :

T-Fal Cooking Pot:

One pet owner reports as follows (from e-mail received on 2/26/2009):

YESTERDAY, 2-25-09, I WAS BOILING WATER IN A SMALL T-FAL POT AND I LEFT THE KITCHEN AND WENT TO THE GARAGE, WHEN I CAME BACK IN THE HOUSE I FORGOT THE WATER WAS BOILING.

I WAS IN ANOTHER ROOM WHEN I SMELLED A STRONG ODOR AND WONDERED WHAT IT WAS. I TRACED IT TO THE KITCHEN AND THE WATER BOILED DRY AND THE FIRE WAS UNDER AN EMPTY PAN NOW.

RIGHT AWAY I GOT A FAN AND CRACKED THE DOOR TO LET OUT THE FUMES.I NEVER THOUGHT TO MOVE THE BIRD TO A DIFFERENT ROOM AWAY FROM THIS MESS.

ABOUT A HALF HOUR LATER I WENT TO PET HIM AND THOUGHT HE WAS A LITTLE “SLUGGISH”. HE DID NOT ACT HIMSELF. HE FELL TO THE BOTTOM OF THE CAGE AND I PICKED HIM UP AND HELD HIM AS HE STRUGGLED TO BREATHE AND THEN DIED IN MY HAND.

I AM FEELING QUITE BAD RIGHT NOW BUT I HOPE THIS EXPERIENCE WILL HELP SOMEONE ELSE TO BE AWARE AND MORE RESPONSIBLE THAN I WAS. THE BIRD WAS A BLUE CROWN CONURE AND PART OF THE FAMILY.”

Teflon Poisoning from an Unlikely Source (Passed on via Forum):

A forum member shared the following experience:

“I know about teflon products and do not purchase them. I do not clean my oven with anything but a plastic scraper and hot hot water.

Saturday Jan 10, 2009 – two days ago -, I put an oven liner that claimed it was made from silicone and was completely safe for animals. I followed the directions, started the oven, popped in a pizza.

Within five minutes of taking the pizza out, my Parrotlet fell to the bottom of the cage and died in my hand. I had no clue what happened to him, I tried to clear his little air way, I thought maybe he choked on something. No luck bringing him back. I have only had him for 5.5 months, but you sure can get attached quickly.

I also have two female caiques, Tango and Daisy. These birds are my children just as for many of you. I wanted to show the girls that little Tucker had passed, so they wouldn’t call for him. I took out Tango (blk.head) showed her that Tucker was gone, she seemed to understand. When I went to take Daisy (wht.belly) (my princess) I have had her for 3 years, when I looked at her she was sitting low on her heated perch, almost squatting. I had her step up, but she had a hard time doing so. Once I had her I could tell something was very wrong, she was wobbly and out of it.

It hit me like a ton of bricks!!!! I had read about this……..That darn oven must have contained some type of teflon or chemical. My roommate and I now in a total panic, rushed the girls outside.

Daisy was fading fast……..I was crying and begging her to stay awake. My neighbors came out to help, they called the local avian vet and had to leave a message. The internet said oxygen……Where am I going to get oxygen at 6pm on a Saturday night??? I was a mess!!! I called the local Fire Dept. I asked them to please, please bring oxygen to save my baby. I must have sounded like a lunatic or something. They came with in fifteen minutes, we put the mask over Daisy’s mouth and her eyes became more alert. I was hopeful. He suggested putting her in a small box and letting the oxygen tube go directly into the box. We got a small box, she seemed to be standing now……..Very hopeful now!

The EMT called the University of Tennessee avian vet. The avian vet said it sounds like telfon exposure. He told the EMT the outcome was not good, but the EMT did not tell us that right away, he could see what a mess we already were. The vet said to take the oxygen off for ten minutes and if she stayed taller that we could bring her to the hospital, but if she faded that meant she had already suffered a lethal dose and there would be nothing he could do for her. Daisy Mae died at 10:15pm, I told her it was bed time and she went to sleep. Tango the survivor was trying to feed Daisy the last hour of her life. It broke my heart.”

Cockatiels can be given tap water for drinking only if it is also safe for human consumption. Unsafe tap water may contain chemicals that can result in lead poisoning. If in doubt of the quality of tap water, it is best to give your cockatiel bottled water for drinking.

So, does this mean you need a huge budget if you want to keep a cockatiel as a pet? Not really! There are many ways to keep your cockatiel healthy by giving it clean and safe drinking water. There are also various methods to make tap water safer for drinking.  

Why tap water is not safe for cockatiels?

Unsafe and untreated tap water can have adverse health effects on your cockatiel because it contains chemicals, as well as biological contaminants. Examples of contaminants include:

• Salts
• Pesticides
• Bleach
• Nitrogen
• Metals
• Toxins
• Bacteria
• Microbes

One of the most common effects of the prolonged consumption of unsafe and untreated tap water in cockatiels is lead poisoning. The following are a few symptoms of lead poisoning in birds:

• Lethargy
• Seizures
• Dehydration

If your cockatiel has been consuming unsafe tap water for some time and is exhibiting the symptoms enumerated above, it’s a must to take it to an avian veterinarian for urgent medical attention.

How will you know if the tap water in your area is safe for cockatiels?

The quality of tap water varies from one location to another and from one country to another. The rule of thumb is, if tap water is not safe enough for humans to drink, it’s also not safe enough for pets to drink.

Most places publish information about the quality of water supplied to homes so contact your city hall or check the city’s website to learn more about the quality of your local water supply. If you have doubts, it is best to serve your feathered friend bottled or purified water.

Is it possible to treat tap water so that cockatiels can drink it?

Tap water, whether for drinking, misting, soaking, and bathing can be treated to make sure it’s 100% free of chlorine and heavy metals. There are various ways to treat tap water and ensure it’s safe for your cockatiel to drink.

Boiling

Boling is the cheapest and safest way to purify water. Bring covered clean water to a boil for about 1-3 minutes and let it cool.

Filtration

Certified water filtration systems come in various shapes and sizes. Choose those that have passed stringent tests and have certifications to prove that they can significantly reduce lead.

Chlorination

Chlorination is another method to treat water and make it safe for consumption. It kills parasites, germs, and other organisms. Off-the-shelf purification products such as chlorine tablets or liquid chlorine can be used for this cheap, yet effective water treatment process.

Remember to only give your cockatiels treated tap water or bottled drinking water.

Is it safer to use bottled water for your cockatiel?

Giving your cockatiel bottled water is the safest option because it eliminates the worries of contaminants and pollutants getting into your feathered friend’s system.

This also eliminates the necessity of having to purify and making the water safe for consumption. The only caveat to this is that the cost can add up over time.

That being said, different types of bottled water are suitable for cockatiels to drink.

Spring water

Spring water is generally considered an excellent choice for the majority of birds, including cockatiels. It’s important to check the label to ensure that it’s natural spring water that comes from natural springs underground.

This water is known to taste better than other types of bottled water and contains dissolved minerals.

Mineral water

Mineral water differs from other types of bottled waters because it has a consistent level and relative proportions of minerals. No further minerals can be added to this kind of bottled water.

Purified water

This type of bottled water is produced by deionization, reverse osmosis, or other processes which meet the definition of “purified water”. However, be very careful NOT to use distilled water because it can cause severe medical problems. It doesn’t have the minerals that are necessary for vital bodily functions.

What can happen to your cockatiel if it drinks the wrong kind of water?

Ideally, before you get yourself a cockatiel or any pet for that matter, you should find out as much as you can about its nutrition and health requirements, temperament, and the best way to care for it, to name a few things.

If you haven’t the time to read about your pet’s water requirements and have only come to realize now that you have been giving your cockatiel the wrong kind of water all this time, it’s not the end of the world yet. 

What you must do is to change to the safe water as soon as you can. However, if your cockatiel has been drinking unsafe water for a long time or is showing signs of lead poisoning as previously enumerated, you need to take it to the avian vet as soon as possible for immediate medical attention.

Final Thoughts

It is perfectly safe to give your pet cockatiel tap water for drinking, as long as it is also safe for human consumption. Furthermore, there are many ways to treat tap water and make it safe for drinking before giving it to your cockatiel. Ultimately, making sure that your pet bird is drinking enough clean and fresh water daily throughout the day is most important.

If you don’t have the time to treat tap water and make it safe for consumption, the best alternative is to give your cockatiel bottled water but only stick to spring water, mineral water, or purified water. You must avoid distilled water as it may result in adverse health effects.

If you have been using tap water for your cockatiel, don’t worry too much. As long as your cockatiel is not exhibiting signs of lead poisoning, it should be fine as long as you immediately change to treated tap water or bottled water.

Avian Bornaviral Ganglioneuritis (ABG) is an immune-mediated disease and is
responsible for what has been previously known as Proventricular Dilatation Disease
(PDD). As many as one-third of the avian population in captivity and in the wild test
positive for the Avian Bornavirus (ABV). Although captive psittacines are the most
impacted, other species also test positive for ABV. ABV does not appear to be zoonotic; humans and animals do not contract this infection from pet birds. It causes disease in the class Aves which includes many species of birds. The Avian Bornavirus may be transmitted both horizontally and vertically. Treatment protocols and proper care are extending the lives of many birds affected with Avian Bornaviral disease. Without treatment, it is usually fatal.

Much of the information available about Avian Bornaviral Disease (ABVD) is now out-of-date. In an attempt to clarify the nature of this disease, researchers now refer to PDD as Avian Ganglioneuritis (AG). The ganglioneuritis may be caused by the Avian
Bornavirus, or it may be caused by another illness. If the bird has not tested positive by molecular diagnostic testing, then the term Avian Ganglioneuritis (AG) should be
applied to the illness, and it only affects the Gastrointestinal System. If it has tested
positive, the term Avian Bornaviral Ganglioneuritis (ABG) is used and it affects both the GI track and the Central Nervous System (CNS). The treatment is the same for both. It is important to have the bird tested for the Avian Bornavirus so the owner can know if the illness is caused by the Avian Bornavirus or another disease state. If the bird does not test positive for the virus, other tests are in order to find the cause.

The term, “Avian Ganglioneuritis” better describes the ongoing disease process and
shifts the emphasis from the proventriculus (gastric stomach) to all the affected organs and systems [4]. This paper’s focus is on the ganglioneuritis and CNS symptoms caused by the Avian Bornavirus, but the reader must keep in mind that Avian Ganglioneuritis can be caused by any one of a number of other illnesses.

The following is a statement by Dr. Bob Dahlhausen with the most current information existing to date. Dr. Dahlhausen is a foremost researcher into this disease and is the veterinarian who first used Celebrex (celecoxib) in his research and with patients.

Avian Ganglioneuritis (Avian Borna Virus [ABV] and Proventricular Dilatation
Disease [PDD])

“Some people think the ABV is just like any other virus: you get it, get sick, and get over it. But ABV is not like that. ABV infection rates are wide-scale. A survey of aviaries in Europe of 1442 birds showed a 23% infection rate. This is similar to the infection rate of wild birds. The average is 30% in almost all aviaries. It is everywhere. One third of birds will contract it.

The dilemma is that a lot of birds have classic PDD signs yet when tested do not have
the Borna virus. What is going on with the pathogenesis? We now know that PDD is an autoimmune disease similar to Guillain-Barre Syndrome.

Throughout the whole nervous system of the bird there are these little proteins called
‘gangliosides’. There are about 50 different ones, and they vary in location throughout
the nervous system of the bird. The virus can expose these proteins, and once they are
exposed, the host’s immune system will mount a cross-reaction to the nerve ganglia
proteins. This causes an autoimmune reaction and disease.

The true role of the Bornavirus is that it can directly or indirectly damage the nerves that cause the gangliosides to be exposed. Then there is another mechanism. It is called ‘antigen mimicry’. That means that infections with agents such as herpesvirus,
Campylobacter and Chlamydophila are so similar to the ganglioside proteins that if the bird’s body mounts an immune response to any of these agents, the immune response will cross-reference to the bird’s nervous system. So we can have infections with these agents, and the bird can show symptoms of PDD when there’s no Bornavirus present.

So many vets and owners think that the Bornavirus infects the bird, the bird gets sick
and gets the disease. The Bornavirus is a cause of PDD signs, but it’s not the only
cause. The dilemma is that birds can have classic PDD signs yet be ABV negative. In
Italy, the researchers have a theory: Can we sensitize the bird against the ganglioside
proteins and produce PDD? Can ganglioside sensitization cause the PDD signs? They
took 8 cockatiels. Three were given ganglioside proteins orally, and 3 were given the
gangliosides by injection. One month later 100% of injected birds and 33% of the birds that received the oral gangliosides developed Central Nervous system (CNS) and gastrointestinal (GI) signs compatible with PDD. The histopathology was identical to PDD. They caused PDD without the presence of ABV. This leads us to conclude that any infection that exposes nerve gangliosides to the host’s immune system and elicits a suitable immune response can produce disease that is compatible with PDD. You can’t tell the difference; many things can cause it. It is true that ABV infection is a cause of PDD, but it’s not the only cause.

When we talk about testing, 1/3 of birds will test positive. A lot of people think that if a bird tests positive, it is a fatal disease. It is going to waste away and die, and it’s very contagious. This is not the case. The majority of birds that are positive are disease-free. The virus is very unstable in the environment. It loses infectivity within 8 hours. It can’t live in the environment, so it does not easily go from bird to bird. In fact, we believe the major transmission is through the egg; the birds are born with this infection. It is not highly contagious via normal routes of exposure. The Italian researchers have taken live birds and put the virus in the nares (nostrils) to simulate inhalation of it and not a single one of those birds became infected.”

Anti-ganglioside Antibody Assay

“This is a new test we are using for ABV/PDD. Testing for the virus is pretty
meaningless with traditional testing methods. There’s a 30% chance your bird will get
sick. What we have now is the Anti-ganglioside Antibody Assay. It’s an ELIZA
(molecular diagnostic blood) test. It measures the antibodies—the immune response of the bird against the ganglioside proteins. This is a much more accurate test. If you have a bird with seizures or is wasting and not digesting well, or wobbly, having ataxia (difficulty balancing and controlling its muscles), this test will show if it has
ganglioneuritis, and we can treat it. Over 98% of birds that were showing clinical
disease symptoms like PDD tested positive on that assay. We’re not testing for Avian
Bornavirus anymore. We are testing for the ganglioside antibodies. We now have really good ways of treating birds. There is a lot we can do for them. PDD, or the wasted bird, is the worst-case scenario. We see a lot of subtle disease before that and varying degrees of disease. We can treat them so they can live a nice, long, healthy life.”

1. Worldwide Distribution and Impact of Avian Bornaviral Ganglioneuritis

The disease, originally known as “Macaw Wasting Disease”, was initially reported in the late 1970’s in the U.S. and Europe. The term, “Proventricular Dilatation Disease”, was given to the disease in a 1983 report describing “impaction, dilation, and degeneration of the proventriculus” [4]. As of 2009, verified cases had been reported in as many as 80 psittacine and non-psittacine species, both captive and wild. Since then, the Avian Bornavirus has been proven to be a cause of Avian Bornaviral Ganglioneuritis and has been detected in birds around the world. This disease “now presents a serious threat to both captive propagation and conservation efforts for endangered psittacines such as the Spix macaw” [4].

2. Defining Avian Bornaviral Ganglioneuritis

The Avian Bornavirus is an enveloped, negative-stranded, ribonucleic acid (RNA) virus. The virus causes Avian Bornaviral Ganglioneuritis which is a fatal, inflammatory wasting disease affecting mostly birds in the psittacine family (Order Psittaciformes) [1]. It is a disorder which impacts the nervous system and causes gastrointestinal and
neurological dysfunction [2]. In pathology terms, it is described as a “non-suppurative,
lymphocytic-plasmacytic ganglioneuritis of the nerve plexi of the crop, proventriculus,
ventriculus, and duodenum and peripheral and central nervous systems” [2,18].

Figure 1. A macaw suffering from Avian Bornaviral Ganglioneuritis. Note the poor
condition of the beak and feathers and depressed stance (image courtesy of R.
Dahlhausen, used with permission).

3. Etiology and Pathogenesis of Avian Bornaviral Disease (ABD)

In the 1970’s, when the great influx of birds from other countries began, captive birds
showed clinical signs of ganglioneuritis, and researchers suspected a viral etiology [2]. In 2010, viral inclusion bodies and enveloped particles were discovered in the myenteric plexus (an arrangement of nerve fibers and neuron cells that are situated within the muscular tissue layer. This layer encloses the esophagus, stomach, and intestines and celiac ganglion of infected birds) [15]. Independent researchers provided confirmation that the etiological agent and pathogenesis of ABG were related to Bornavirus. This novel genome was named “Avian Bornavirus” [1,15]. The connection between Borna Disease Virus (BDV) and Avian Bornaviral Disease was established using qPCR (Realtime Polymerase Chain Reaction) [2].

Avian Bornavirus has been found in tissues of the brain, proventriculus, plasma, crop,
ventriculus, duodenum, liver, lung, kidney, spleen, retina, cerebrum, cerebellum and
adrenal glands of infected birds [2]. Gancz was able to transmit the infection by
inoculating birds with tissue from ABV-positive birds. Not all developed signs, but all
were found to have the characteristic lymphoplasmacytic infiltrates in the myenteric
ganglia (collection of nerve groups within the intestinal tract) and variable degrees of
lesions in the brain and spinal cord [15].

ABG had previously been regarded as carrying a high-mortality but low-infection risk. As of a few years ago, it has been shown to occur much more frequently but involve a “low incidence of clinical disease and a much lower incidence of severe disease” [12]. New treatment protocols have moved this disease to a more chronic state and one which often responds to treatment. Nevertheless, an infected bird will never eliminate the viral infection [2].

3.1 The Parent Disease: Borna Disease Virus

Borna Disease Virus was originally discovered in cavalry horses in Borna, Germany in 1885. Since that time, it has become known as a “neurological disease of a wide range of animal species and possibly humans” [2,4].

Most viruses spread by cell-to-cell contact, first invading and destroying the host cell,
then moving on to infect more cells. Borna Disease Virus, however, uses the “nuclear
compartment of the host cells in which infectious ribonucleoproteins are present for
transcription and replication” [15]. The virus does not destroy the cell, so infected cells suffer very little damage. Additionally, the virus has developed several methods to avoid being recognized by the host immune system [2,3]. “This is a detection-evasion strategy which allows the molecules to go unrecognized by the cytosolic RNA sensor that triggers the host’s innate immune response” [15]. To accomplish this, the virus must suppress apoptosis (natural cell death.) The result is continual and lifelong infection for both Bornavirus and Avian Bornavirus. ABG is now known to be an immune-mediated disease [15].

Avian Bornavirus is different from Bornavirus —it does not grow in mammalian cell
lines; therefore, it is not thought to infect humans or animals [2]. BDV attacks are limited to the central nervous system; however, ABV affects the innervation of multiple organs: the brain, GI tract, liver, kidneys, heart, and lungs, as well as in the peripheral blood vessels [3]. ABV is a neurotropic virus: It attacks the central, peripheral and autonomic nervous systems. There is a wide range of signs from the infection. In some birds, only slight changes in behavior are noted, but in others, the birds suffer severe neurological disease which results in fatal infections [2,4].

4. Infection Rates

Practitioners have been reporting high numbers of birds testing positive for ABV. Lierz
detected ABV RNA in 45.8% of normal birds [10]. In a 2010 study of molecular samples from 791 psittacines, ABV RNA was discovered in 34.3% of the samples. In a later study, 100+ psittacines living in a stressful shelter situation were tested, and 52% of this population tested positive for ABV-specific RNA. In some densely populated shelters, even higher numbers of birds have tested positive [3].

5. The Avian Bornavirus and its Genotypes

The term “genotype” refers to the genetic makeup of an individual virus. As of 2017, the family Bornaviridae contained a diverse viral group of 15 different genotypes. Of those, genotypes 2 and 4 are frequently found in psittacine species [18]. Viral shedding is intermittent; therefore, a sample taken when the virus is not being shed will test negative for the virus. Additionally, the virus is very unstable and will degrade quickly, producing a negative test result. Finally, not all birds with Avian Ganglioneuritis test positive for Avian Bornavirus [2].

6. Detection of Avian Bornaviral Disease

Clinical signs vary from infrequent mild episodes to sudden and acute illness [10]. A bird may experience just some of the signs, but not necessarily all. Some birds becomesymptomatic years or decades after becoming ABV-infected, and some never show signs at all but may continue to shed the virus and thus infect other birds [4]. Healthy birds can experience viremia (the presence of the virus in the blood) due to ABV without becoming clinically ill [2]. In fact, most of the ABV-positive birds do not display clinical disease [12].

6.1 Challenges Encountered When Testing for Avian Bornaviral Infections

• Lymphoplasmacytic ganglioneuritis (infected nerve groups), pathological lesions, or a similar disease state may be caused by other infectious agents [1,2]. One other virus, paramyxovirus-1, may cause the same ganglioneuritis signs as ABV disease [2].
• Some psittacine species are more vulnerable to specific genotypes than others.
• The various ABV genotypes may each produce distinctive and specific clinical signs. This may explain why some birds develop certain signs and others experience different signs, and why some birds, when exposed, do not contract the virus at all.
• There are minor variations, but they all produce the same general pathology [2].
• Some reported primer sequences used in ABV Reverse-Transcription Polymerase Chain Reaction (RT-PCR) testing do not detect all identified ABV genotypes [2].
• “While the virus can be detected in cloacal swabs from both clinically and nonclinically infected birds, cloacal swab samples are not consistently positive in affected birds, possibly due to the high level of RNA enzymes in fecal material that can destroy viral RNA and the inconsistent shedding of the virus” [2].
• Other destructive factors may be present, like bacteria, enzymes, or other contaminants found in the feces [4]. These artifacts can result in a false negative test result.

7. Species Affected by the Avian Bornavirus

Psittacines appear to be the most affected by the Avian Bornavirus; as a result, almost
all of the studies have concentrated on the captive psittacine population. The species
with the highest number of positive results were cockatoos, Amazons, Eclectus, African greys, and macaws. Quakers and lovebirds have been minimally represented. Those with the lowest number were cockatiels, budgerigars, pionus and conures [4].

7.1 ABV in Wild Psittacines and Non-psittacine Species

Investigations of ABV infection in wild psittacines had not been conducted until recently. In 2011, more than 80 free-ranging, clinically healthy psittacines were tested for ABV. The birds were located in Brazil and belonged to seven different species. The results revealed that 33% tested positive for genotype 4, and 50% of the birds possessed antibodies to the virus [7]. Avian species other than psittacines are vulnerable to ABV, specifically waterfowl. In 2011, researchers tested Mute Swans, Snow Geese, Ross’ Geese, and Greater White-fronted Geese. ABV was detected in all but the Whitefronted Geese. Of the ducks tested, 11% of ducks and 13% of gulls tested positive. Acute encephalitis (inflammation of the brain) was found in geese and swans. Bald Eagles have been found with the virus; it is assumed that raptors could be vulnerable through predation [3,13]. Canaries (order Passeriformes) have been found to be infected with ABV. One canary showed signs of apathy just three days before it succumbed to the virus [11]. The lesions found in it were similar to the lesions found in the psittacine birds with ABV disease. Both neural and extraneural tissues contained Bornaviral antigens (a substance that evokes an immune response from the body) [6]. A second canary’s illness was chronic. The symptoms included prolonged depression, CNS (Central Nervous System) signs, and visual impairment with chorioretinitis (ocular inflammation)” [12]. Cortical blindness may occur in canaries. It often responds to treatment (R. Dahlhausen, personal communication).

8. Periods of Vulnerability

8.1 Young Birds

Unweaned birds are more vulnerable to ABV infection than adults. The estimated
incubation period is between two and four weeks or longer [6]. Avian Bornavirus’
ordinarily long incubation period is shorter for the immunocompromised or very young
with incomplete immune system development [13].

8.2 The Breeding Season

Hormonal and reproductive activity often give rise to new cases and relapses of
previous cases. The disease cycles from active to dormant states, and the stresses of
this increased hormonal state depress the immune system, allowing clinical disease to
flare up [2]. One clinician has treated a patient who had experienced severe relapses of gastrointestinal symptoms during four consecutive breeding seasons [2]. Each
consecutive relapse diminishes the bird’s ability to fight the disease and further
damages the organs.

9. Development of Signs

In some naturally occurring flocks, ABG is described as a “sporadic disease” [2]. Even
single pet birds, housed in the same environment for many years, have been diagnosed with the disease. The clinician should not automatically assume a bird is afflicted with ABG simply because it tests positive for ABV. It might take years before an ABV positive bird develops signs of ABG, and some never become symptomatic. It is not known if or when the bird will become symptomatic or what will trigger the onset of disease [6].

9.1 Factors in the Bird’s Reaction to the Presence of the Virus

ABV disease is “defined by the absence or presence of antigenemia” (having an antigen in the blood) [2]. Each of the following factors will influence or change the way the bird reacts to the virus, and these signs differ from case to case. R. Dahlhausen attributes the development of clinical disease to the following predisposing factors:

• Genetics, age, host species, and ABV genotype involved.
• Severity of the disease, distribution of lesions, and involvement of affected organ systems [4].
• The developmental competency or compromised condition of the host’s immune system [2].
• Stress due to malnutrition, concurrent disease, reproductive activity, and improper husbandry. Stress is generally accepted as the primary predisposing factor in the activation or recurrence of ABG [2].

10. The Avian Bornavirus’ Effect on the Systems of the Body

Avian Bornavirus primarily affects the CNS and nerves of the gastrointestinal tract [4].
Birds may exhibit only GI or CNS signs, but some experience both, and the virus usually affects both, even if they are not initially obvious.

In a 2015 survey conducted by Dahlhausen and Orosz, 66% of birds exhibited CNS
signs, 22% experienced GI tract signs, 9% displayed feather picking and mutilation, and 9% suffered acute death [4].

10.1 Gastrointestinal Signs of Avian Bornaviral Disease

“Avian Bornaviral Ganglioneuritis is a persistent inflammation of the networks of nervous tissues due to the invasion of lymphocytes and plasmacytes into the nerve ganglia of organs of the upper digestive tract” [2,14,18]. Affected birds are unable to digest or absorb their dietary nutrients properly. Sometimes, secondary bacterial or fungal infections of the GI tract result from poor motility.

The GI signs indicate pathology of the vagus nerve (Cranial Nerve X) [4]. The GI
symptoms develop from the disruption of innervation to the vagus nerve [12]. This nerve “supplies the proximal (upper) portion of the intestinal tract—from the crop,
proventriculus and ventriculus to the duodenum and the heart” [12]. When the vagus
nerve malfunctions, the normal GI motility is altered, and the wall of the GI tract
becomes thin [12]. This can result in the rupture of the proventriculus and immediate,
very painful, death.

“Finding the infected nerve ganglia confirms that the individual is suffering from Avian
Ganglioneuritis” [12]. Clinical signs include:

• Depression
• Weight loss and abdominal enlargement
• Muscular and neurogenic atrophy
• Crop stasis and regurgitation- Polyuria (excessive urination)
• Weakness and loss of body condition
• Passage of undigested food in the feces
• Poor absorption and impaired GI tract transit
• Polyphagia (excessive eating) [12].

As long as the intestinal tract is distended, the proventriculus and ventriculus will not become fully emptied; motility will be inhibited, and gastrointestinal stasis may result [4].

Figure 2. Droppings containing undigested food (image courtesy of
www.vetexotic.theclinics.com, used with permission).

Figure 3. Displacement of the organs due to dilated proventriculus. “This bird was very thin with a very prominent keel bone and pectoral muscle atrophy. The crop and
proventriculus were markedly dilated and filled with soft oats. The proventriculus filled 80% of the cranial coelom and displaced the liver dorsally and to the right. The
ventriculus was displaced caudally and displaced the intestines dorsally. The intestines contained a small amount of brown liquid.” (vetpath.wordpress.com, used with permission).

Figure 4. Necropsy photo of a crop containing undigested foods. Whole seeds can be
seen in this picture (image courtesy of Avian Genetics, used with permission).

Figure 5. Necropsy photos showing the displacement of organs caused by dilated
proventriculus and ventriculus. The large, pale, center organ (the proventriculus) and
the smaller, yellowish extension of it (the ventriculus) are displacing the lungs, kidneys, heart, and liver (image courtesy of R. Dahlhausen, used with permission).

Figure 6. A necropsy photo displaying the wasting effect of the disease in a cockatoo
(image courtesy of R. Dahlhausen, used with permission).

10.2 Neurological Signs of Avian Bornaviral Disease

CNS lesions are usually found in the cerebrum or cerebellum. Disruptions of the cell layers within the cerebellum produce disorders in fine-muscle movement and equilibrium [4]. The affected bird may display:

• Ataxia, lack of coordination, difficulty balancing
• Intention tremors, head tremors, seizures
• Progressive paresis, paralysis, motor and proprioceptive deficits [4]
• Aggressive behavior, feather plucking, and self-mutilation due to peripheral neuritis
• Anorexia, moaning or crying due to digestive discomfort
• Reduced cognitive ability
• Dysarthria (vocalization abnormalities)
• Hypersensitivity to sensory pain, discomfort, and sensory input [2,4]

Old World species often exhibit CNS signs and may experience concurrent, non-clinical lesions in the GI tract as well [4]. The nervous system signs are more difficult to control and more rapidly fatal than the GI signs.

Figure 7. Neurological signs of self-mutilation (image courtesy of R. Dahlhausen, used with permission).

Figure 8. Signs of self-mutilation in an African Grey (image courtesy of R. Dahlhausen, used with permission).

10.2.1 Self-mutilation and Feather Destruction

In 2011, Fluck et al., substantiated the correlation between ABV infection, neurological signs, and feather-picking behavior [7,8]. This study yielded the following results:

• 42.5% of the birds tested positive for ABV infection in one of the test systems.
• 24% of the birds in the control group tested positive in at least one of the ABV tests, compared to 54.1% of the feather-plucking birds and 68.4% of the neurologically diseased birds [8].

Other Organs Affected by the Avian Bornavirus

ABV resides in a wide variety of tissues in the body, not just the GI tract and nervous
system. Viral RNA has been discovered in the liver, kidney, adrenal glands, eyes, heart, and lungs [2]. When ABV attacks the myocardium (the heart muscle), clinicians find lesions in heart muscle fibers, indicating myocarditis (inflammation of the heart muscle) [18]. Lesions have also been found in the “conduction pathways of the heart, causing sudden death in birds which previously appear normal; these lesions also affect the heart rate” [1,2,14]. Enlargement of the right ventricle of the heart, arrhythmias, and alterations in blood pressure have been noted in affected birds [4].
Avian Bornavirus is also responsible for disorders of the eyes, leading to optic lobe
lesions and blindness [4]. The birds which were infected with ABV and were clinically ill experienced lesions within the retina of the eye, leading to decreased visual acuity [9]. In the case of cortical blindness, the eye is functioning properly, but the nerves between the eye and the brain have become infected. In most cases, the eyes respond to correct treatment [2,4].

12. Transmission

12.1 Horizontal Transmission

In a 2009 study, Rinder et al., detected ABV in numerous organs and tissues of infected birds. Since then, they discovered viral nucleic acids in the fecal and cloacal swabs of infected birds. They concluded that the virus is transmitted by the fecal, oral, and nasal routes [6]. It was thought that birds must come in close contact with the saliva and fecal matter of an ABV-positive bird to become infected [2,4]. The virus only lives eight hours outside the host, so it does not readily pass from bird-to-bird (R. Dahlhausen, personal communication).

Although some consider the virus to be highly contagious, others believe it is more likely to be spread in homes and aviaries in which good hygiene is not practiced. Some
clinicians believe that it is essential that the affected bird be isolated from others in the flock [2,16]. Others agree that isolation is necessary in a shelter or breeding situation, but in a home, practicing careful hygiene and maintaining distance between the affected bird and other birds are usually sufficient to prevent transmission.
In research studies, live virus was gavaged into normal birds and dropped into the
nostrils of normal birds, and not a single bird converted to positive, infected status.
Horizontal transmission is very difficult to demonstrate experimentally and usually
requires injection of the virus into the bird to be transmitted (R. Dahlhausen, personal
communication).

12.2 Vertical Transmission

While vertical transmission was suspected, it was not proven until recently. It is now
considered to be the primary cause of Avian Bornaviral transmission in birds. Helga
Gerlach, a renowned avian pathologist, believes it is passed through the vitelline
membrane of the egg (R. Dahlhausen, personal communication.)

13. The Importance of Screening

If there are three or more birds in a collection, and ABV is present among them, routine screening is advisable. Use of the Anti-ganglioside Antibody Assay for birds that are exhibiting clinical disease that is compatible with ABV is recommended in order to prove that the signs observed are due to avian ganglioneuritis. It does not prove that they are caused by ABV [2].

The high number of asymptomatic birds or those with latent ABV infections makes it
difficult to manage large populations of birds [2]. It is almost impossible to maintain an ABV-free collection. One negative test does not mean that the bird is clean; birds must be tested at least three times or more to be sure a bird is negative for ABV, and even then clinicians cannot be 100% positive. Today, clinicians determine that it is prudent to test for ABV at the same time as they test for other diseases so that treatment of those showing clinical disease can begin sooner. Screening is vital for the management of subclinical infections. Buyers need to have confidence that their new bird is healthy, and aviary owners need to know that any bird entering or leaving has tested negative for ABV [1]. Molecular diagnostic screening allows the clinician to determine if a bird is ABV- infected even before the bird demonstrates clinical signs [6].

Figure 9. Necropsy photo showing the dramatically reduced pectoral mass in a lory.
Wasting occurs when the proventriculus dilates as the disease progresses. The
proventricular wall thins due to muscle atrophy from altered innervation. Reduced
absorption of nutrients causes the bird to lose muscle mass (image courtesy of R.
Dahlhausen, used with permission).

14. Diagnostics and Testing

14.1 Differential Diagnoses

There are other diseases or conditions which can cause the same gastrointestinal signs as Avian Bornaviral Ganglioneuritis. The following may be causes of “wasting” condition in birds:

• Tumors or papillomas of the crop, proventriculus, ventriculus, and intestines. The
  presence of internal papillomas may lead to a chronic wasting signs similar to
  ABG.
• Ingestion of foreign bodies and heavy metal poisoning [4].
• Megabacteriosis, parasitism, inflammatory disease, and neoplastic diseases,
  causing gastrointestinal stasis.

Other conditions or diseases that produce similar CNS signs in birds are:

• Traumatic injuries, neoplasia, hydrocephalus.
• Nutritional deficiencies
• Viral, bacterial, and fungal infections of the CNS [4].

14.2. Testing

Practitioners rely on various tests to give them a conclusive diagnosis of Avian Bornaviral Ganglioneuritis. Molecular assays, serology, radiology, and histopathology
are the standard diagnostic tests available to detect ABV. Crop biopsies are useful in
locating inflammatory infiltrates in the neural tissues, and radiographs show the
distension of the proventriculus, ventriculus and other GI organs. However, one
drawback to both radiography and crop biopsy is that they must be performed when the bird is displaying advanced clinical signs [6].

14.3 Standard Testing Protocols

• Radiographs and CT-Scans: Contrast radiography is used to diagnose the dilatation of the proventriculus and the duodenum and to determine the time it takes for ingesta to pass through the GI tract [15].
• Crop Biopsy: A section of crop and a prominent blood vessel are removed and examined. The presence of lymphoplasmacytic ganglioneuritis in the crop tissue is required for a positive result [1]. False-negative crop biopsies occur at least one fourth of the time due to the varying distribution of lesions [2]. Biopsies must include infected ganglia; if these aren’t present, the test will come back negative, even if the bird is not displaying signs of nerve damage [2].
• ELISA (Enzyme-linked Immunosorbent Assay): This is a serology test which looks for immunological exposure to specific ABV antigens. It is a binding test used to detect either antigens (proteins) or antibodies in the blood. There is not a consistently reliable ELISA test commercially available at this time.
• Molecular Diagnostics: These tests detect shedding of Avian Bornavirus. Direct Real-time Polymerase Chain Reaction (rt-PCR) detects the presence of ABVspecific RNA [1].
• Anti-Ganglioside Antibody Test: This is a non-invasive serology test which detects the presence and increased levels of anti-ganglioside antibodies in the blood. It accurately detects immune-based ganglioneuritis, regardless of the causative agent [16].
• The Western Blot Assay is capable of identifying the N-Protein which is “associated with ABV infection in the brains of affected birds” [2]. This assay has detected antibodies against the Avian Bornavirus [6]. However, “recommendations regarding the application of this assay to the antemortem (live) diagnosis of ABV in pet birds have yet to be determined” [2].

14.4 Molecular Diagnostics

Standard testing may allow a tentative diagnosis of Avian Bornaviral disease; however, with the standard tests, only histopathology findings are definitive, providing proof of nerve destruction in the proventriculus, ventriculus and brain [2]. “Due to its sensitivity and specificity in detecting nucleic acid targets, PCR is one of the most important toolsin viral diagnostics” [2]. Identification of the ABV genome has allowed researchers to use PCR testing in tissue samples [5,6]. The use of RT-PCR has allowed clinicians to detect ABV ribonucleic acid (RNA) in affected birds. Today, “identification of lymphoplasmacytic ganglioneuritis provides a definitive diagnosis of Avian Ganglioneuritis” [2,4]. “The standard tests continue to be performed, but they are now ancillary to the more sophisticated genetic testing. Avian Bornaviral Ganglioneuritis should be considered as a possible differential in any bird with CNS and GI signs” [2].

“Not all infected birds show positive serology. That is part of the diagnostic dilemma. The bird has probably not contracted the disease, and the PCR should validate that.
The real dilemma is that not all ABV-positive birds develop detectable antibodies or
disease. Some birds with avian ganglioneuritis are ABV negative but demonstrate
disease that is indistinguishable from Avian Bornaviral Ganglioneuritis. They do have
avian ganglioneuritis but it is due to another etiology, not ABV. Birds that demonstrate avian ganglioneuritis may or may not show detectable antibodies and may or may not be ABV positive. The best diagnostic assay is one for anti-ganglioside antibodies. This confirms that the bird’s illness is due to avian ganglioneuritis, regardless of ABV infection status” (R. Dahlhausen, personal communication).

15. Treatment

• Celebrex: Selective Cox-2 inhibitor (celecoxib). To treat ganglioneuritis in the
  central, peripheral, and autonomic nervous systems; inhibitor for GI tract signs,
  pain, and inflammation.
• Robenacoxib: Cox-2 inhibitor, injectable, non-steroidal anti-inflammatory agent
  used to treat pain and inflammation from ganglioneuritis.
• Metoclopramide: GI prokinetic agent for nausea and vomiting, easing digestive
  discomfort.
• Gabapentin: for self-mutilation, seizures, neurological/neurogenic pain.
• Cisapride: GI prokinetic agent for improving transit in birds with GI tract
  involvement, particularly early in the course of therapy.
• Leuprolide acetate and Deslorelin implants: for managing hormonal increases
  which occur with the onset of breeding activity.
• (Specific dosages may be obtained by consulting Carpenter’s Exotic Animal
  Formulary, 4th Edition)

15.1. Supplementation

Some supplements have been shown to aid in the improvement of the quality of life of
affected birds:

• Antibacterial and antifungal therapy is advised to “control overgrowth of intestinal
  anaerobes, yeasts, and Macrorhabdus. GI tract disease “alters the intestinalmicrobiome,” so probiotics, prebiotics, and prokinetics may aid in restoring
  normal the intestinal environment. These are more effective early in the course of
  therapy [4].
• Vetomega: Omega fatty acids 3,6,9 are helpful in reducing inflammation.
  Available from Scott Echols.
• Semi-elemental diets, such as Lafeber’s Emeraid Omnivore and Carnivore
  Critical Care Nutrition diets. These need very little digestive effort from the bird
  because they are hydrolyzed; they contain the essential nutrients and Omega
  fatty acids and are easily absorbed [4].
• Herbal supplements like silymarin (milk thistle), Gaia herbs, and ginger are
  “helpful in reducing inflammation, preserving hepatic function, and improving GI
  tract transit” [4]. The liver is often affected by the bacteria coming from the
  abnormal intestinal environment [4].

Although some dietary supplements have been used to treat Avian Ganglioneuritis,
none has shown consistent, positive results. The addition of supplements has proven
useful in alleviating some of the adverse effects of the disease [4].

16. Recommendations to Clinicians

• Begin treatment to alleviate clinical disease signs. Once eliminated, treatment for
  the inflammatory component is necessary only if the signs recur in the future.
• Wait before euthanizing a bird in order to give treatment protocols a chance to
  work.
• Be careful when choosing the lab for ABV PCR testing and test interpretation due
  to the inability of some tests to detect all genotypes.
• Repeat testing in affected flocks. Testing of apparently negative birds is strongly
  suggested for the highest reliability in diagnosis of ABV infection. However, this is
  not always practical due to the prohibitive cost. Strict isolation is advised [2,17].

17. Recommendations to Owners

Long-term survival does not mean that the bird has been cured. It still carries the virus and is a potential source of transmission to other birds [2]. To minimize the chances of the virus spreading within the home or aviary, clinicians should advise their clients to observe the following recommendations:

• Avoid overcrowding.
• Pay attention to hygiene. This is particularly important for owners who keep
  multiple birds. Scrupulous, constant attention must be paid to cleanliness. Immediately remove feces, vomitus, and dust, and disinfect all inanimate objects
  with which the bird has come in contact. This is vital in the prevention of the
  spread of the disease [17].
• Clean all surfaces and objects, such as toys and food/water dishes, frequently, to
  avert transmission through fomites.
• Take proper precautions to clean any exposed skin (particularly the hands and
  arms), and change clothing after handling the affected bird.
• Keep the aviary or home adequately ventilated.
• Provide superior nutrition and clean water daily.
• Avoid stressful conditions, particularly in aviary collections and in shelters.
• Do not smoke around the bird. Second-hand smoke and the use of other tobacco
  products inhibit the immune system. Smokers should not handle the bird unless
  they have cleansed their arms and hands thoroughly and changed clothing; the
  toxins on the skin can cause pododermatitis and lesions on the legs and skin.
• Isolate or remove any ABV- exposed and ABV-positive birds from the rest of the
  population in high-density situations, and separate them in home environments
  as needed [2].
• Do not wait to euthanize until the bird is nearly dead. The proventriculus can
  rupture, causing a quick but extremely painful death.

Conclusion

Although clinicians have been aware of Avian Bornaviral Disease for many years, many clinicians and bird owners have an incomplete understanding of this complex viral infection and disease process. Its spread may be curbed by close monitoring of flocks and prevention of the reproduction of ABV-positive birds. Hopefully, bird-keepers have gained sufficient awareness about the dangers of ABG to be vigilant regarding the signs and to have their birds tested before the disease progresses to a critical stage. By offering their birds a quality diet, providing correct medications, and decreasing stress levels, they may afford the ABV-positive bird a longer lifespan and a considerably enhanced quality of life.

Images copyrighted February, 2016. All rights reserved. Images may not be reproduced or used without the express written consent of the owner.

References

1. Clubb S, de Kloet S. A Comparison of Crop Biopsy, Serology, and PCR for
   Diagnosis of Subclinical Proventricular Dilatation Disease. Proc Annu Conf Assoc
   Avian Vet. 2009:3-9.
2. Dahlhausen R. Avian Bornavirus and Proventricular Dilatation Disease. Proc
   Annu Conf Assoc Avian Vet. 2010.
3. Dahlhausen R, Orosz S. Avian Bornavirus Infection Rates in Domestic
   Psittacine Birds. Proc Annu Conf Assoc Avian Vet. 2010: 13-15.
4. Dahlhausen R, Orosz S. Avian Bornaviral Ganglioneuritis in Clinical Practice.
   Proc Annu Conf Assoc Avian Vet. ExoticsCon, 2015.
5. De Kloet AH, Kerski A, de Kloet SR. Diagnosis of Avian Bornavirus Infection in
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   Polymerase Chain Reaction Assay Using Feather Calami. J. Vet. Diagn. Investig.
   2011 May: 23(3): 421-9. Source: Animal Genetics, Inc.
6. Dorrestein G. Avian Bornavirus, The Most Likely Cause for Inducing
   Proventricular Dilatation Disease (PDD) in Parrots, A Review. Diagnostic
   Pathology Laboratory. Poultry Conference at the Wroclaw University of
   Environmental and Life Sciences, July 11-22, 2011.
7. Enderline D, et al. Avian Bornavirus Infections in Free-Ranging Psittacines
   (abstract). In: Proc Int. Conf on Avian, Herpetological and Exotic Mammal
   Medicine: 349-350. Apr., 2013.
8. Fluck A, et al. Avian Bornavirus infection in Psittacine Birds with Neurological
   Signs and Feather Plucking (abstract). In: Proc Int Conf on Avian, Herpetological
   and Exotic Mammal Medicine. 2013:388.
9. Korbel R, Rinder M. Ocular Findings in Psittacine Birds Infected with Avian
   Bornavirus (ABV). Proc Annu Conf Assoc Avian Vet. 2012:21.
10. Lierz M, et al. Do we Understand Avian Bornavirus in Psittacines? Proc Annu
    Conf Assoc Avian Vet. 2011:19.
11. Lierz M, et al. Vertical Transmission of ABV in Psittacines. Emerging
    Infectious Diseases. 2011 Dec, Vol 17(12), Dec. 2011.
    wwwnc.cdc.gov/eid/article/17/12/11-1317_article
12. Orosz S. Unraveling the Puzzle of Avian Bornavirus and PDD. In: Avian
    Medicine. LafeberCares.com. Posted on Sept. 24, 2012.
13. Payne S, et al. Presence and Impact of Avian Bornaviruses in Waterfowl.
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14. Rinder M, Kronthaler F, Hufen H, Korbel R. Avian Bornavirus Infections in
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All rights reserved. This document is available on-line at www.ivis.org. Document No.
R01168.0219

Article by:  Jeannine Miesle, M.A., M.Ed

Birds, like any other animal, thrive as adults when the parents have raised them to abundance weaning and fledging. The trend of hand-rearing began in the 1980’s when thousands of birds were taken from their habitats and placed around the world. In most countries, hand-raising because the acceptable method of breeding since the parents weren’t tame, and breeders feared they would not know how to raise the chicks in captivity. It has done irreparable damage to both the parents and chicks over the decades. Breeders need to allow the parents to once again take charge of the rearing of their chicks, which is much easier on the humans as well.

Introduction

There are three methods of raising chicks: by the parents or foster parents feeding them to abundance weaning while people socialize them by handling them (co-parenting); by human (artificial) means only, known as hand-feeding or hand-raising; and by both parents and humans, both engaging in feeding (still considered hand-feeding).

The arguments for and against hand-rearing of birds in the Psittacine family abound. Hand-rearing has been the accepted technique by breeders, buyers, and some veterinarians for more than 40 years, and most veterinarians have not discouraged the practice. During that time, studies have been done by researchers and veterinarians on the benefits and drawbacks associated with this practice

There are two valid reasons for hand-raising chicks: The first is to preserve a species that is in danger of extinction due to of the enormous number of birds of that species captured in the wild and the destruction of habitat. Many have died in the process of being captured, shipped, quarantined, and sold to people not knowledgeable about bird care, leaving very few of the species left in the wild or even in breeding programs. Breeders of these species fear the parents may harm the chicks or not feed them well, so they pull the chicks hand-feed them. In these cases, hand-raising will significantly reduce the potential for eggs being broken in the nest or parental neglect. This is frequently done in zoos and wildlife institutions.

The second reason is to prevent eggs and/or chicks from being harmed by parents who have a history of damaging eggs or attacking the chicks. One reason for parent birds harming or neglecting the young is that they have not been permitted to care for the chicks themselves in the past, and they are acting out of frustration.

Image 2 : Three chicks that had to be hand-raised because their parents abandoned them (image credit Dawn Dandve; used with permission).

1. Hand-rearing: An Historical Perspective

During the bird craze of the 1970’s, 1980’s and 1990’s, with the influx of so many wild-caught birds, breeding became big business. These birds were wild and aggressive, so breeders assumed that their offspring would be uncontrollable and aggressive, too. Even after importation of wild-caught parrots was banned in many countries, breeders continued to hand-rear in order to produce tame birds for the pet trade. They assumed that if they took the eggs and chicks away from the parents and raised the babies by hand, the birds would bond with people instead of their wild parents and thus would make better pets. At the time, it was considered the best method of preparing the birds to be tame pets which would form a strong bond with the owner. It was cost-effective for the breeder since it prevented losses due to broken eggs, accidental injuries, and abuse or neglect from the parents. 2

Removing the eggs and incubating them artificially, away from parents, has been done for a long time—and this practice needs to stop! It is unnatural and results in many deaths in the egg and after hatching. Chicks are deprived of the comfort and bonding with their parents and siblings. Again, it’s thought that they’ll bond better with humans, which is not true. It creates maladjusted, often crippled and neurotic chicks, and frustrated parents.

Breeders argue that the pairs will lay multiple clutches a year, thus bringing in more money for them. Selling them before they were weaned also brought them in more money since they didn’t have to wait as long for the sales, and new owners loved the idea of hand-feeding their new chicks. Breeders also contend that hand-reared birds are more tame and trusting of humans and consequently would become more desirable and enjoyable pets which would sell quickly. Even though now, many generations later, the original wild-caught birds have long since died, and the chicks we have seen in the last 20 years are now the descendants of tame birds, the practice has continued and still persists today. 2

For those who breed on a large scale, greed takes precedence over the needs of the birds. Most birds on the market today are produced in bird mills and sold in pet shops. It is from these mills that poorer quality, often unhealthy, diseased birds come. Neither the parents nor the chicks receive medical care, and their husbandry and quality of life are sub-standard. They are force-weaned, clipped to prevent flight, and sold to anyone who will pay the price. Some breeders never give their birds a break from breeding; both males and females become exhausted, malnourished, sick, and eventually die. The hens in particular die from calcium deficiency, egg-binding, cloacal prolapses, and other reproductive illnesses. Many of the chicks either die, or are of such poor quality for not having received superior quality and quantity nutrition and care, that they are not sellable; nor do they make good breeding stock, and so they are culled. Eggs are pulled and artificially incubated, or chicks are pulled from the nest after two weeks or sooner to be hand-fed. 2

The Netherlands now has legislation preventing breeders from hand-feeding their chicks and separating the parents from the chicks.

Information on avian welfare legislation – Appendix I 

Of course, there are reputable, small-scale breeders who do rest their birds so that they do not become exhausted by overproduction of chicks in a short amount of time. They provide quality nutrition and veterinary care and thus raise healthy, hand-fed chicks. There are still two crucial factors missing, though: the needs of the parent birds to complete the reproductive cycle by caring for their babies, and the needs of the chicks to be with their parents and siblings and learn how to become independent, self-confident adults. 2

So this begs the questions: Are these bird breeders really achieving their goals of making a profit if chicks die from poor breeding and hand-rearing techniques? Do the chicks necessarily become better pets for having been pulled and hand-fed? And is producing such birds truly advantageous if there are more negatives attached to this practice than positives?

2. Hand-rearing Techniques

Most pet birds that are reaching the pet market today have been hand-raised. Breeders either take the chicks from the parents and nest at a very young age and at an early stage of development and raise them in brooders, or they pull the eggs from the nest, incubate them artificially, and hatch them outside the nest. After that, the chicks are raised by humans and hand-fed with a hand-raising formula from a spoon, syringe or crop needle. (See Figure 1) If the birds had been allowed to hatch in the nest, they are often pulled from the nest at approximately two weeks of age. This is about the time that the eyelids open. The hand-raised baby birds are kept in brooders or tubs, either singly or in small clutches, and are hand-fed until weaning. In the wild, parents whose chicks are lost due to predation or in-shell death will see this as nest failure and begin the reproductive cycle again. The same thing happens with captive birds. This is how breeders get the birds to lay multiple clutches within the year, thus earning them additional income 2

Image 4: Hand-feeding with a syringe. One can see how easy it would be for someone not experienced to cause beak trauma (image courtesy Kelly Vriesma; used with permission).

Image 5: Another method of hand-feeding is using a spoon (image courtesy “Hand-rearing guide for beginners”).

3. Meeting the Needs of the Hand-raised Chick

If the breeder has no choice but to hand-rear the chick, he should make every effort to meet the bird’s physiological, behavioral, and emotional needs as it goes through each phase of its development. In addition, if the breeder raises neonates together in an enclosure instead of in individual containers, he may be able to avoid the abnormal developments often seen in hand-reared birds. These groupings should consist of birds of a similar age and species. “Mixed species and mixed-age settings, however, may also yield good results, whereby the young birds seek touching, sleep readily, play with, and are curious about others. Thus, this method poses as a suitable alternative that is widely accepted and used by breeders nowadays.” 12

Image 6: When neonates are raised together, as in the case of these blue-and-gold macaws (Ara ararauna) , the risks of abnormal behavioral development are decreased (image courtesy Lorenzo Crosta in Speer: Current Therapy in Avian Medicine and Surgery).

4. Significance of the Studies on Hand-rearing of Psittacine Birds

From the 1990’s up until today, some breeders, aviculturists, and veterinarians began to notice that the hand-feeding of birds was not working. Studies have been done during the past three decades on the advantages and disadvantages of hand-feeding, and comparisons were made between chicks that were parent-raised and those that were hand-raised by humans. Except for the need to care for the chick whose parents abandoned, neglected, harmed, or refused to feed the chick, or hand-rearing in order to preserve the species, there are no advantages for the parents or chicks in hand-feeding; in fact, there are many disadvantages. 11

In these studies and observations on the effects of egg-pulling and hand-rearing, it became obvious that hand-reared chicks were not as healthy, either physically or psychologically, as were their parent-raised counterparts. In addition, many breeding pairs refused to breed anymore; in fact, many will crush eggs, harm, or neglect the babies out of frustration at not being permitted to raise their chicks as nature intended. They refused to engage in the reproductive cycle. 11

5. Responsibilities of Breeders and Potential Owners.

Hand-feeding and hand-raising birds continues to this day, even though research has shown it is not beneficial for the chicks or parents. It is also very time-consuming and stressful for the breeders to keep up this practice.

Practitioners, aviculturists, pet-shop personnel, breeders, potential buyers, and bird owners need to be educated about the potentially harmful effects hand-raising has on birds. Breeders should be encouraged to replace hand-rearing of their chicks with parent-raising and

Co-parenting (handling of birds during the time the parents are raising them.) This way, the birds would be allowed to be in their nests for several weeks after weaning, allowing them to become socialized with other birds and ensuring that their development is based on self-orientation as birds. Those seeking to purchase should be encouraged to seek out parent-raised birds and instructed about what to look for in a new bird prior to its purchase. 2 Allowing the parents to raise them for a few weeks, then pulling them for hand-feeding is not co-parenting; it is still hand-feeding.

6. Observations of Professional, Small-scale Breeders and Owners

I have received several messages from hobby breeders and owners on this topic. They sent their perspectives on hand-feeding, parent-feeding, and co-parenting. As former hand-feeders, they have seen a dramatic improvement in the quality of the birds since they have begun co-parenting, and their birds are in high demand.

Comments by owners and breeders on the advantages of parent-raised birds – Appendix II

7. A Highly Respected Avian Veterinarian Compares Hand-raised and Parent-raised Chicks

In his studies, Brian Speer makes the following observations as he compares hand-raised and parent-raised birds and their wild counterparts:

“Hand-fed parrot chicks in captivity receive human socialization, feeding, grooming and vocal contact from their hand-feeders. Parent-raised birds are fed and reared by their parents, with copious amounts of parental time invested in direct contact, feeding, vocalizing, grooming and physically contacting them during their development.

After these hand-fed young are fledged or weaned, however, they typically are sold into the pet trade with no further broadening of their social education necessarily planned or recommended. Parent-raised birds learn to fly and explore their environment with and from their parents, learn to recognize and communicate socially with other conspecifics (birds of the same species), and learn how to forage and recognize environmental hazards.

Owners of hand-fed birds persist with close physical contact, vocalization, preening and other parent-to-chick types of behaviors with their own mental picture that this type of contact and relationship is representative of a “quality” or “bonded” pet bird relationship. However, the chicks fail to learn the social skills necessary to make them good companion birds. Parent-raised birds learn social skills from their parents that enable them to live a healthy, happy existence.

The young, hand-reared parrots grow to the age of sexual maturity with virtually no learned social or communication skills other than those they received since hatching, making them unable to possess the necessary sexual maturity to effectively reproduce. However, at sexual maturation, parent-raised birds have learned social communication skills which allow them to be in sexually mature, monogamous pairings within a reproductive pair bond.

Those species that rely most heavily on learned, social-behavioral interaction skills and are hand-raised are more predisposed to problems than those species that are not as dependent. Parent-raised birds have few, if any, behavioral difficulties due to learned social interaction skills.” 11

Image 7: A rescued chick that would not have survived without handfeeding (image courtesy Nousin Mun; used with permission).

8. Disadvantages of Hand-raising Chicks

Many of the chicks:

• Didn’t hatch.
• Were deformed and thus were euthanized.
• Became ill since they hadn’t received the immunity from their parents.
• Died before they had a chance to mature due to poor handling and feeding methods.
• Imprinted on people to the point that they became neurotic and very needy pets.
• Suffered from stunted emotional development so intense that they could not be apart from the human for any length of time at all, for the rest of their lives, thus exhibiting neurotic behavior such as screaming, feather-picking and self-mutilation.
• They experienced stunted social development in that they feared other birds, did not know how to interact with other birds, or how to entertain themselves when left alone. 11

9. Hand-rearing Complications

Once the birds are a few weeks old, they are forced to wean, whether they are ready or not. The humans decide when to remove the babies from the nest, when and how to incubate the eggs, and when it is time for the chicks to be weaned to solid foods, such as pellets, seeds, fruits and vegetables. “This man-made definition of weaning is very different from that which occurs in the wild or in parent-raised breeding situations.” 2

Image 8: Single bird living in a small container away from the nest and parents and siblings

(image credit World Parrot Trust, https://www.parrots.org/about-wpt/position-hand-feeding, http://www.echobonaire.org/; used with permission). :

9.1 Forced Weaning of Hand-raised Birds is Physically Harmful to the Chicks

“Hand-reared chicks are forced to wean at a very early age, sometimes months earlier than would occur naturally.

Weaning of hand-raised birds generally starts at the time when the birds fledge and is often completed after two weeks.

After fledging, the birds are more difficult to control and often have their wings trimmed prior to developing adequate flight skills. This often results in damage to the wings, inability to fly ever again, crashes to the floor and damage to the keel, vent, and abdomen.

The birds are weaned onto solid foods for which their digestive tracts are not sufficiently developed.

Sale of the birds occurs as soon as weaning has been achieved. Birds are often sold prior to weaning so the birds can bond to the new owner. This is extremely detrimental since many owners have very little, if any, knowledge of how to correctly care for and wean the birds.

These birds have essentially been raised in isolation from the time that they can see. They have only seen humans providing a food source, and there is minimal socialization for any of these birds with other birds. They are then sold into generally a single bird household.” Parent-raised birds are raised and live in a flock. So living in a single-bird home is unnatural for them 2

Image 9: Healthy, parent-raised chicks, 3 ½ weeks old (image courtesy Jerry Randall; used with permission).

10. Behavioral Issues Associated with Hand-reared Chicks

Image 12: Three of this pair’s chicks at 3 weeks (image courtesy Alona Samorodska; used with permission).

11. Comparison of Emotional and Social Developmental between Hand-raised and Parent-raised Birds

Parrots are a highly social species, and their “visual, tactile, and auditory development is greatly influenced by interaction with parents and siblings.” 12 Hand-reared birds consider humans part of the flock, and this means that parrots will become accustomed to being handled and having physical contact with people. In order to achieve this level of comfort with humans, hand-rearing “has long been the accepted method, as it is thought to help strengthen the human–psittacine bond, thereby resulting in a bird that is more attached to humans and able to positively interact with people.” 12 However, the lack of parent involvement and interaction with other birds of its own species “can severely impact the emotional and social development of the captive psittacine bird and result in displays of abnormal behaviors.” 12

11.1 Social Relationships

Social relationships may be disrupted as well when birds are hand-raised. Hand-reared parrots are often more inclined to prefer social contact with their humans than with other birds.

However, birds that were raised by the parents and also handled by humans during the neonatal period (i.e., five, 20-minute sessions per week), preferred the companionship of humans and other birds of their species equally. Van Zeeland infers from this that hand-raising is more disruptive of a bird’s social development than the stresses of being tamed. 12

Chicks who are brooded and reared by their parents, in contrast, have many advantages over hand-raised chicks. “The brooding and rearing of chicks by the parents is far more beneficial for the chicks’ emotional and social development. 12See “The Importance of Parental Nurturing” – Appendix IV11.2 The Babyhood Crisis, from The Well-fed Flock. This article is so important it belongs in the body of the paper.

Most pet birds never receive a proper babyhood that helps them develop robust mental & physical health. This is never spoken about because it has become so normal & accepted, as too have the effects this improper babyhood can go on to have in later life. In this article we look at the babyhood crisis in companion Birds & how we can facilitate a positive babyhood at home.

WHAT SHOULD PARROT BABYHOOD BE LIKE?- In their natural environment, Parrots learn from their flock during varying timescales after they fledge the nest. This can range from months to (in some larger Parrots) several years. During this time they are shown by adult role models how to forage for food, what foods are safe, what behaviors are expected & how to cope with stress & danger. They are often still partly parent fed during this time until they ‘find their wings’, reach sexual maturity & find partners of their own. As a society, we severely overlook the crucial role of this babyhood & the function of role models to show safe foods, build social understanding & help the young Bird learn to regulate their emotions.

WHAT IS A DOMESTIC BABYHOOD LIKE?– This of course depends on where they hatch & what understanding caregivers have of babyhood, but it’s rarely what they need. Most hand reared chicks are removed from parent Birds before they ever learn they are a Bird because ‘good companions’ must think they are human. Their early days are spent being fed by humans & the chicks don’t hear the vocalizations of their parents, feel their parent Bird’s feathers against their skin or look up to see their parent(s) & thus begin to learn what species they are. They often spend weeks in plastic tubs with rows of other chicks of varying ages who also are deprived of early days of same species bonding, sensory input & interaction.

Image 11: Loving parents feeding their baby (image courtesy Alona Samorodska; used with permission).

The chicks are then weaned, often far earlier than nature intended & are placed in cages or aviaries. They have no adult Birds to show them how to fly, climb, eat or behave. No role models to show them how to engage in healthy & natural behaviors such as same species bonding, foraging or stripping bark from branches. The chicks eventually find their way (although they often develop very subtle unhealthy methods) but even happy looking chicks feel anxious during this time. They are then pre-wired for anxiety with no adult Bird to model healthy coping strategies to deal with it. This is when we see the increased rate of stereotypic behavior & feather plucking/ skin picking that is seen in hand reared Birds. These behaviors may not be seen until well into adulthood, but the anxiety starts this early on & we don’t even see it. They also often see humans as their mate because they have been raised as ‘mini humans’. This isn’t touching, funny or cute when they try to mate or feed you, it’s heartbreaking.

Parent reared chicks usually have more robust mental health long term & have those vital early interactions between parent & chick. Sadly parent reared Birds are still taken away much earlier than nature intended & they too seldom have a chance to fully learn these important behaviors. When these chicks go home, they then rely on human caregivers to show them correct & healthy foods to eat, how to eat them & model calm, well-regulated behaviors that put their new baby at ease. Sadly most baby Birds enter homes who have different priorities.

HOW HOMES HARM BABY BIRDS- Our priority should be a relaxed babyhood, teaching natural behaviors such as foraging & appropriate chewing & showing how to eat nutritious foods. The priority of most families with a new Bird is compliance, tameness, entertainment & speech. People will stand for hours & bombard the bewildered baby with trick commands & say the same word over & over again in their face to try & get them to talk, but claim there ‘is not enough time’ to show them how to eat vegetables. These bombarding sessions are often very overwhelming for the young Bird who has just left everything they know & has no time to settle in. Most baby Parrots are quite slow learners & some even learn skills one day & forget them the next, this can wind caregivers up (especially when the perfectly normal biting phase starts). Birds are social animals & need caregivers to mirror behavior for them to learn. Baby Birds grow up seeing often frustrated & wound up behavior & this teaches them that the environment is stressful & stress responses are normal. This coupled with the anxiety they have already experienced leads to so many of the ‘problem behaviors’ we see later on. The misunderstanding & mishandling of hormonal behaviors increases this problem.

A GOOD BABYHOOD– Just slow down, be calm & enjoy the ride! It’s not a race. The chick doesn’t need to be bombarded & doesn’t need to learn everything all at once. Spend time together where the two of you ‘just BE’. Take natural teaching opportunities that arise & accept the fact that they aren’t mini people, but a beautiful species in their own right. Be around them with calm breathing & a steady pace of life, model calm & gentle behaviors. We often feel as though we need to be ‘in their face’ & bombarding them with instructions for them to learn & develop, but this isn’t how they learn by nature.

Be a role model who models calm, open & loving behavior & eat healthy things such as fruit & vegetables in front of them & unhealthy things away from their view. Avian mental & physical health is ALWAYS the priority, compliance & performance should never be seen as more important. Expose them to a wide array of nutritious foods, foraging activities, toys & safe objects & allow them to explore in their own way. We don’t need to constantly hover over them or micro manage their play, we just need to be their safe space if they need help or reassurance. I have rescued so many elderly Birds who never had a proper babyhood & every one of them went through a ‘delayed babyhood’. When surrounded by the right care & environment they just let go of all the anxiety & tension & really started to act & play like a baby. Some of them were already several years older than the life expectancy of their species, they just laid there & didn’t move when they arrived, but then became flooded with youth. A youth that was so wrongly denied to them for so many years, Let’s make sure this never happens again.

Image 13: This image shows what a typical hand-rearing nursery looks like. “After the incubation of the eggs, the birds are hatched and the chicks placed in large nurseries for hand-rearing. In this nursery setting, the birds are housed alone or in groupings with other birds of the same species. These large nest-bins can be pulled out to allow them to socialize with the other chicks who share their bin and those in the bins next to them. When these nest-bins are rolled in, they provide a secure, dark nest cavity. However, this method of chick-rearing is not as preferable as leaving them with the parents; they are not receiving the attention and socialization that are necessary for development that they would normally receive from the parents” (text and image courtesy Yvonne Van Zeeland in Speer: Current Therapy in Avian Medicine and Surgery).

When placed in these bins and rolled in to darkness, the birds are entirely alone, which is terrifying for chicks. They need the parents and siblings to be secure.

12. Comparison of Growth Rates between Hand-Raised and Parent-raised Chicks

In order to hand-raise birds, breeders will place the eggs in an incubator or remove them from the nest, separating them from the parents just after hatching. This disrupts the instinctive parental care the parents give the birds and is extremely stressful to them and the chicks. It “disrupts the normal behavioral and physiologic development of the bird.” 12 For example, a study on growth rate differences between hand-reared and parent-raised chicks showed slower growth rates in the hand-reared chicks. 12

13. Imprinting, Reproduction, and Sexual Maturation among Hand-reared Psittacines

If birds are cross-fostered to other species or raised by humans, they are more likely to imprint on their caregivers. They “learn to identify with these foster parents or caregivers, and may choose these as their preferred social and sexual partner after maturation.”: 12

Most of the time, cockatoos (Cacatua spp.) are more likely to display these behaviors as opposed to South American parrot species (macaws, Amazons, conures), but birds from any species can exhibit these aberrant behaviors. Birds which have imprinted on humans or have been improperly reared “may develop inappropriate reproductive behaviors as a result (e.g., impairment of normal copulatory behaviors and laying of eggs on the floor) and are less likely to successfully reproduce.”: 12 These undesirable behaviors may not be the same in the males and females. For example, the hand-reared male may not inspect the next box as he should, and he may not reach a desirable level of fertility. The female does not seem as affected by it as the male, which demonstrates that males are more strongly influenced by sexual imprinting than females. 12

Image 14: Lovebird parent feeding chicks (image courtesy YouTube; permission unavailable).

14. Vocalization Differences between Hand-raised and Parent-raised Birds.

In studies, hand-raised birds and parent-raised birds differed in their abilities to learn human and species-typical vocalizations. These differences were in both the extent and speed at which they learned to vocalize. Hand-reared birds were capable of imitating human speech at an earlier age than parent-raised birds. They were also able to mimic these sounds found in human speech at an earlier age and to a greater extent than parent-reared birds; however, they were unable to “produce the species-typical vocalizations until placed with normal vocalizing conspecifics for at least a week.” 12 These differences were the result of the increased, earlier level of social interaction “whereby the extensive exposure to human speech and human contact function as positive reinforcement. This, in turn, results in hand-reared chicks that quickly master the ability to talk.” 12 However, that should not be the primary goal of the breeder or potential bird-owner.

To some bird owners, the ability of a bird to talk is one of the main reasons for getting the bird; however, these individuals have not been educated to understand that this is not nearly as important as the companionship the human will get from the bird and the care and attention the bird will receive from the human. This should be made clear to the prospective buyer.

15. Comparison of Physical Development and Injury between Parent-raised and Hand-raised Birds

Parent-raised birds also have increased physical advantages. “The limited movement of a group of chicks within the nest box, for example, provides them with the necessary support for the appendicular skeleton to develop properly. Chicks raised individually in incubators, in contrast, lack the support of the nest and siblings and frequently move around (allegedly in search of parental or sibling contact). This excessive moving around has been associated with a significantly higher incidence of bony deformations and osteodystrophy” (abnormal bone development). 12 It is true that deformities such as splayed legs can happen with both hand-raised and parent-raised chicks, but the numbers are by far higher with hand-raisedbirds.

Image 15: Cockatiel chick that was rescued and hand-raised by Nousin Mun who has a rescue center in Bangladesh. In this case, hand-raising saved the bird’s life since his parents abandoned him, but he has splayed legs. She has worked with him to bring the legs together (image credit Nousin Mun; used with permission).

Image 16: This hand-fed chick has difficulty with his feet since he is not in the nest with his siblings (image courtesy Nancy Watters; used with permission).

16. Physical Illnesses and Conditions Brought About by Improper Hand-feeding

17. Diseases

Mother Nature’s way of parent-rearing always has a higher success rate. The chicks have a strong start since parents will always rear their chicks to completion.Darrel K. Styles, DVM

Image 28. Healthy, parent-raised chicks (image courtesy Jerry Randal; used with permission).

17.1 Bacterial Infections

Unweaned birds are particularly susceptible to bacterial infections. The causes are poor husbandry and an immune system which is not fully developed. Hand-feeding practices are the primary cause of crop infections: “Over feeding, feeding too frequently, improper formula temperature, or feeding before the crop empties can all lead to bacterial overgrowth. Primary viral infections destroying the immune system underlie severe secondary bacterial infections in young birds. Spontaneous, primary bacterial infections are uncommon in young birds when proper husbandry is practiced.” 9

Image 26: Porridge formula was too hot and infection set in, causing major damage to the crop (image credit Galabin Mladenov; used with permission).

Image 27: Surgery was required to close the significant fistula between the crop and the outside (image credit Galabin Mladenov; used with permission).

17.2 Illnesses due to malnutrition

Amino acids and proteins are the building blocks of life. They are organic compounds that combine to form proteins, and protein is broken down into component amino acids before being absorbed by the intestines. Amino acids are required for optimal health, but the body cannot synthesize them; they must be provided in foods or supplements. The terms, “EFA’s” and “amino acids” are used interchangeably. EFA’s refer to the Omega-3, 6, and 9 fatty acids. Most hand-rearing mixes for psittacines and pelleted diets lack sufficient quantities of the Sulphur amino acids (methionine and cysteine). 5

17.2.1 Rickets

Without sufficient Ca/D3 there is not enough calcium present to harden the bones in growing birds. This occurs mainly in hand-reared birds whose mineral intake is unbalanced. It is also termed, “Rubbery Bone Syndrome.” 4

17.2.2 Hepatic lipidosis

Hepatic lipidosis, or fatty liver disease, is caused by high-fat foods, B-vitamin deficiencies, and obesity. It is a slow, on-going, progressive disease in which the liver tissue is replaced with fat. Juvenile, hand-fed birds that are overfed or hand-fed long after they should have been weaned are often diagnosed with it. Hand-feeding formulas are calorie-dense, and baby birds tend to be sedentary; any extra calories tend to end up being stored as fat in the liver. This is most often seen in cockatoos as they tend to beg even after satiated.5

18. Co-parenting: The Ideal Method of Raising Chicks

Many veterinarians and aviculturists are now encouraging breeders to allow the parents to feed and raise them to weaning. Humans are able to help with the care, and as they continue to handle the chicks, the chicks become socialized to humans; thus, the parents are able to fulfill their instinctive reproductive responsibilities. So all concerned have the best of both worlds. Adults get to feed and care for their babies, humans don’t have the round-the-clock feedings, and babies grow up into healthy, mature adult birds. The result is well-adjusted birds who aren’t constantly desperate for their chosen person’s attention.

Of course there are exceptions: Parents who harm their babies or refuse to feed them must have the chicks removed from the nest, but if the aviaries are kept in the correct manner, this doesn’t usually happen. Co-parenting leads to well-adjusted birds who aren’t desperate for their person’s attention all the time. Many species take a considerably longer time to wean than humans allow them. Money is the root of this problem; there is not a quick turnover if chicks are allowed to be with the parents for a longer time

Fortunately, increasing numbers of breeders nowadays are allowing parents to incubate, hatch, and raise their chicks themselves until fledging. Human interaction with these chicks may then either begin in the nest box when the chicks are about two weeks old or after the chicks have successfully fledged. Using these methods, the juvenile birds are accustomed to human handling via brief daily interactions while still able to benefit from the interactions with their parents and siblings. Particularly, the co-parenting technique appears successful at producing offspring that are less responsive to stress and well-socialized to both humans and parrots. In addition, this method increases the chances of the chicks displaying normal reproductive behaviors once they mature since they had more intense contact with the parents and siblings than with humans. This often lowers the cost, time, and effort involved in successfully raising the chicks compared with conventional hand-rearing techniques. Human contact with the neonate may, however, also increase the risk of abandonment, abuse, or infanticide. As a result, the co-parenting technique may not be applicable to all species and individuals, especially those that appear prone to poor parenting. 12

Image 29: Indian Ringneck father feeding the chicks. As Nature Intended.

Conclusion

The days of hand-rearing as an accepted method of rearing chicks are over, but many breeders refuse to discontinue the practice. For some, it’s a habit they’re afraid to break, as they think it will decrease the numbers of birds they can sell. For others, they enjoy the process so much they don’t want to give it up because of the pleasure it gives them. But with co-parenting, they can still enjoy handling the birds and offering other foods once, and even before, the birds are totally weaned, giving them ample opportunities to bond with the birds.

That bond can only be had in a nurturing, warm, loving environment. A hand-raised chick will not be sweet and loving if all that’s done is feeding him and leaving. These chicks need to be held, talked to, and have time spent with them to become the ideal pet. It doesn’t matter if he’s hand or parent fed; unless the humans engage him and give him attention, he’ll still be wild.

Rearing chicks by hand is completely unnatural in the normal lives of birds. If breeders would take the current thought to heart and allow their babies to be parent-raised and co-parented, they would find their birds would be in greater demand since the purchasers would be more satisfied with their birds than with birds from breeders who have hand-raised their birds. In the long run, then, these successes would attract more clients.

The purpose of this paper is not to vilify those who choose to hand-feed. And the physical and psychological issues may occur in any chick, whether it is hand-fed or not. Not every hand-fed chick will experience physical or psychological issues; and not every parent-fed chick will grow to maturity without them. These are generalizations gleaned from many years of research, experimentation, and observation. The purpose is to persuade the breeder who hand-raises to consider allowing the parents to raise the chicks while still being actively involved in their handling and development.

Knowledgeable veterinarians, bird owners, and aviculturists must continue to educate breeders and future companion-bird owners as to what to look for in a companion bird. They need to know of the potential difficulties that can result from the development of abnormal human-bird bonds and the potential for physical, social, and emotional damage from hand-feeding. We encourage new bird owners to seek education from their avian veterinarians and other respected aviculturists.

In the words of Pamela Clark, “The solution? If you really love parrots, then vote with your dollars. Simply refuse to purchase unweaned babies. Don’t purchase babies who can’t fly because their wings were clipped before they ever had a chance to fledge. Don’t purchase a baby who is ‘weaned’ at an age before they would have fledged in the wild. Don’t purchase a baby whose early beginnings are going to commit him to a life of dependence, fear, and behavior problems. Educate yourselves and then drive this market toward improvement. We don’t want family members that have been reared by ‘farming industry practices.’ That is the answer. You are the answer.”

APPENDICES

• Appendix I: Animal Welfare Issues and Their Influence on Legislation  
• Appendix II: Comments from “The Science of Avian Health” Members and Breeders

• Appendix III: Pamela Clark: Early Beginnings for Parrots

• Appendix IV:  Position: Hand-feeding: World Parrot Trust

REFERENCES

1. Bennett A. Avian GI and Reproductive Surgery. S. Eur. Vet. Conf. 2010 Reprinted in the IVIS website with the permission of the SEVC http://www.sevc.info www.ivis.org

2. Gallagher A. The Human-bird Bond and its Impact on Companion Bird Behavior. Brisbane Bird Vet, Chermside (agallagher@brisbanebirdvet.com.au)

3. Jiménez J. Avian Dermatology: More than Feather Picking. Proc Southern Eur. Vet. Conf (SEVC)

2008. Reprinted in the IVIS website with the permission of the SEVC http://www.sevc.info, www.ivis.org

Jones M.P. How I Diagnose and Manage Nutritional Disease. In: Proc North Amer Vet Conf, 2007. Reprinted in International Veterinary Information Service (IVIS) with the permission of the NAVC.

4. Macwhirter P. Malnutrition. In: Avian Medicine, Principles and Application. Spix Pub, Inc., 2006.

5. Miesle J. Nutritional Requirements of Companion Birds, International Veterinary Information Service (IVIS): Reviews in Veterinary Medicine, June 11, 2019 and in the files of the Facebook group: The Science of Avian Health.

6. Paul-Murphy J., et al. Animal Welfare Issues and Their Influence on Legislation: Advancement in Management of Welfare for the Avian Species. In: Current Therapy in Avian Medicine and Surgery, B. Speer, Ed. Elsevier Pub. Co., 2016. p.681

Management of Welfare for the Avian Species.  In: Current Therapy in Avian Medicine and Surgery, B. Speer, Ed. Elsevier Pub. Co., 2016. p.681

7. Paul-MurphyJ. Avian Gastrointestinal Disease. Proc Latin Am Vet Conf (LAVC) 2014.

8. Phalen, David N. .Crop Stasis in a Fledgling Blue and Gold Macaw. Proc NAVC N Am Vet Conf  2005 Reprinted in the IVIS website with the permission of the NAVC http://www.ivis.org/

9. Rosenthal KL. Microbiology: Revisiting the Gram Stain and Culture. In: Proc NAVC 2006

10 Speer B. Surgery of the Head and Beak. Proc N Am Vet Conf (NAVC) 2005

11. Speer B. The Pet Bird/Owner Reproductive Pair Bond. In: Sex and the Single Bird, Proc Assn. Avian Vets 2003, Reprinted in the IVIS website with the permission of the NAVC

12. van Zeeland Yvonne R.A., Friedman Susan G., Bergman L. Behavior: Consequences of Hand-rearing Psittacine Birds. In: Current Therapy in Avian Medicine and Surgery, B. Speer, Ed. Elsevier Pub. Co., 2016. p. 119, 120, 193-196

Pamela Clark’s References:

Feenders, G., & Bateson, M. (2013). Hand rearing affects emotional responses but not basic cognitive performance in European starlings.  Animal behaviour, 86(1), 127–138. doi:10.1016/j.anbehav.2013.05.002

Fox, R. 2006. “HandRearing: Behavioral Impacts and Implications for Captive Parrot Welfare.” Manual of Parrot Behavior. Ed. Andrew Luescher. Ames: Blackwell Publishing.

Linden, P. G.  1993. “Abundance Weaning.” The Pet Bird Report.  Issue #13. September/October 1993. Volume 3, Number 5. Pages 18 – 21.

Linden, P. G. 1994. “Fledgling Stress Syndrome.” The Pet Bird Report.  Issue #19. Volume 4, Number 5. Pages 42 – 44.

Linden, P. G. 1995. “The Developmental Impact of Weaning.” The Pet Bird Report. Issue #20. Volume 4, Number 6. Pages 4 – 10.

Linden, P. G. 1995. “Eating Skills for Recently Weaned Chicks.” The Pet Bird Report. Issue #23. Date unknown. Volume 5, Number 3. Pages 38 – 45.

Linden, P, G. with Leuscher, A. 2006. “Behavioral Development of Psittacine Companions: Neonates, Neophytes, and Fledglings.” Manual of Parrot Behavior.  Ed. Andrew Luescher. Ames: Blackwell Publishing.

Meder, A. (1989), Effects of hand‐rearing on the behavioral development of infant and juvenile gorillas (>Gorilla g. gorilla). Dev. Psychobiol., 22: 357-376. doi:

Appendix 1: Animal Welfare Issues and Their Influence on Legislation

Article by:  Jeannine Miesle, M.A., M.Ed

Main Article: Hand-raised or Parent-raised: Which Is Better For The Birds? by Jeannine Miesle M.A., M.Ed.

Appendix I: Animal Welfare Issues and Their Influence on Legislation

Because of public pressure on legislators, animal welfare laws are being passed in some countries. The Netherlands has passed laws regarding the hand rearing of psittacines. These laws prohibit the separation of immature animals from their parents, include parrots. Reports have described the welfare problems that can be caused by the separation of young animals from their parents, detailed which species were currently at risk, and proposed criteria for preventing problems caused by such separation. Final legislation was passed in 2014. 4

The parent–chick separation law in the Netherlands is also likely to be enforced and should improve avian welfare by preventing hand-feeding by inexperienced owners and allowing proper socialization of psittacines, hopefully decreasing the behavioral problems often seen in these birds. Like the laws pertaining to animal cruelty, the bird-specific laws implemented to improve avian welfare will only be useful if they are enforced. Also, although these laws are meant to educate the public and improve avian welfare overall, such education is possible only if their availability is widely known. For the sake of improving avian welfare, it is worth the effort to discover what guidelines are available to help ensure at least minimally adequate husbandry for pet birds. 4

The sale of unweaned psittacines is an example of legislative issues regarding avian welfare. “Public pressure has resulted in laws addressing this practice in California and the Netherlands, but the matter has not been tackled in most jurisdictions. In Australia, some states allow the sale of unweaned birds (to knowledgeable buyers) and some do not. Whether or not bans on such sales become more common throughout other countries and states will depend on the politics of public pressure and industry resistance as played out on the worldwide scene.” 4 

Pet Birds: Appendix III: Early Beginnings for Parrots

Article by:  Jeannine Miesle, M.A., M.Ed

Main Article: Hand-raised or Parent-raised: Which Is Better For The Birds? by Jeannine Miesle M.A., M.Ed.

Appendix III: Pamela Clark: Early Beginnings forParrots

https://blogpamelaclarkonline.com/2019/09/11/early-beginnings-for-parrots/?fbclid=IwAR3wpVpB87ys_3z4ZnLcPQm13IDn9slaof0yqI0Q4EJH0OtS4gBuX217SZQ:

Pamela Clark’s references are available on the linked page (scroll down to view).Used with permission

Phoebe Greene Linden was ahead of her time. Back in 1993, 26 years ago, she published an article that talked about Abundance Weaning™, a term she coined and trademarked. The latter fact is amusing today; it’s not like hordes of breeders since have tried to steal the term. They remain mired in their practices of force-weaning (also called deprivation-weaning) baby parrots.

Phoebe began a crucial conversation, one that remains unfinished today. She brought an ethical focus to the rearing of baby parrots that took into account also the well-being of the breeding birds themselves. Her concerns were both ethical and practical. Her ideas flew in the face of the prevailing wisdom of the day. According to Phoebe, breeding parrots should have large enclosures and plenty of enrichment. Baby parrots must be fledged and allowed to develop excellent flight skills. Flight ability should never be removed from a parrot all at once. Fledglings needed to be abundantly supported as they developed their independent eating skills and provided with lots of enrichment to encourage their desire to explore.

I recently did a Google search for the term “abundance weaning” and found websites describing this method, without any reference or credit to Phoebe. In addition, they have bastardized the initial ideas that Phoebe developed. Unfortunately, a full description of this process is not within the scope of this post, but this is a word to the wise. Abundance Weaning™, as Phoebe developed it, incorporated a great deal more than simply allowing baby parrots to wean when they were ready. (Linden, 1993)

As Phoebe writes: “Abundance weaning is a segment of a process of nurturing that begins with hand-feeding and should not end in this lifetime for our feathered companions. Abundance weaning contributes significantly to the well-balanced psychological development of the young parrot: it provides innumerable opportunities for owner and baby to bond deeply in a spirit of trust and plenitude, it encourages the development of physical skills in a non-threatening environment; it is the cornucopia from which springs fullness and peace. Would that every creature on this earth be given the abundance we can provide to our special feathery messengers.” Phoebe was my mentor when I reared African greys back then. I emulated her practices with excellent results. The greys I produced were different from those of other breeders. They were bold, eager to engage, confident and coordinated.

I wasn’t the only one who put into practice what Phoebe taught. There were other small breeders who bred parrots purely for the love of the species and the ability to do a really great job fostering their development. However, our ethics got the better of us. We were all small breeders, a lot more in love with the birds than the money. Gradually, we came to see that no matter how well we screened adoptive homes, things often did not turn out as we might have wished for our offspring.

My own experience included babies who were lost forever outdoors, those who gradually spent more and more time in their cages and began to destroy feathers as a result, those who did not receive the guidance I had taught their new owners to provide, and those who suffered due to the insensitivity of those who adopted them. I learned that, when screening potential adopters, you never really get to see what is truly bedrock in the person. Most of us who were colleagues back then stopped breeding as a result of similar experiences, leaving the field open to production breeders and those for whom the money is more important than the ethics. I have often quoted avian specialist Dr. Brian Speer: “Aviculture is the only farming industry that produces family members.” If that doesn’t send a chill down your spine, I don’t know what will…that is if you love parrots like I do for their innate qualities.

We humans are incredibly slow sometimes to recognize the truth… slow to learn and slow to change. Chris Shank’s last blog post revealed some profound comparisons between what her fledgling Star is learning and the more typical experience baby parrots have today at the hands of breeders. Essentially, Chris brought up the same conversation that Phoebe began 26 years ago.

It always kills me that Facebook posts and those on other social media sites are so full of parrot love, and yet the manner in which we breed and rear baby parrots withstands no real scrutiny at all. No one seems to care how our baby parrots are produced, as long as they are there for our consumption when we want them. The only exceptions to this come from a few like Phoebe, Dr. Speer, Chris, and others like them who occasionally toss out a verbal or written volley in hopes of keeping the conversation alive and refocusing our attention on what is most important.

Is the manner in which we rear parrots in captivity really important?

Do methods really matter?

There is abundant research that documents both developmental and behavioral abnormalities in a large number of hand-reared species, indicating that early conditions for animals are of critical importance. Feenders and Bateson discuss several conclusions previously reached by other researchers:

· “In humans, poor parenting and adverse experiences during early development are associated with impairments in adult cognitive ability and an increased risk for developing psychiatric disorders such as anxiety, depression and psychoses.”

· “In rats,Rattus norvegicus, maternal separation produces long-lasting changes in emotional behavior and impaired responses to stress. Maternal separation induces reduced neurogenesis in the adult hippocampus and consequential impairments in learning and memory.

· “In rhesus monkeys,Macaca mulatta, removal from the mother followed by peer rearing or rearing by mothers experiencing variable foraging conditions produces adults with more reactive stress physiology, increased anxiety, impulsivity and aggression and behavioral abnormalities such as motor stereotypies.”

· “Adverse events during early development have been shown to increase the likelihood of developing abnormal behavior, and specifically motor stereotypies, in a range of species. For example, animals removed from their mother at an earlier age, and animals born in captive as opposed to natural environments, show a higher incidence of stereotypic behavior.”

· “In birds, there is some evidence that manipulations that involve elements of hand rearing affect the adult phenotypes similarly to the effects observed in mammals.”

Rebecca Fox comes to similar conclusions regarding parrots: “Abnormal sexual imprinting and a strong social preference for humans may cause behavior problems in pet parrots, which are probably more likely to inappropriately direct sexual behavior at their owners. Hand-reared birds may exhibit other behavior problems as well, most notably so-called “phobic” behavior.” (Fox, 2006) Phoebe Greene Linden and Andrew U. Luescher provide a detailed comparison of observable behaviors exhibited by both hand-reared and wild Amazon parrots in Santa Barbara, California through all stages from hatching to fledging and the development of independent eating skills. They comment upon the importance of fledging: “Sadly, the majority of psittacids raised for the companion market will not experience a true fledging process and may never actually fly because their environments are not provisioned for such development.”

“Space, time, and commitment limitations abound, and some aviculturists contend that fledging is unnecessary or extravagant. The question remains: Can a suitably developed psittacine companion who never flies remain a viable lifelong pet? That answer to that question depends, of course, on what environments shape the experiences during the time of development normally occupied by flight and after.” (Linden,P. 2006)

There you have only a taste of the research available, which documents the deleterious effects of hand-rearing on both mammals and birds. The conclusions are unanimous – the process of hand-rearing carries with it significant impact upon the developing young animals and will impact them throughout their lives.

Serving as companion to this body of science stands our own anecdotal evidence. Dogs and cats who were hand-reared are typically quite different, displaying abnormal and problematic behavior that often encompasses aggressive tendencies. I once had a bottle-fed black cat who would come up behind unassuming visitors and bite them hard on the back of the leg. That adorable bottle-feeding kitten evolved into an adult cat who caused a lot of problems.

So…yes. The manner in which our companion parrots are reared matters. It is critical to their entire life experience. I often assist owners in locating adult parrots for adoption and during the transition once the parrot is home. I can state with certainty that well-reared parrots adapt very differently, and much more easily, to their new homes. (By “well-reared,” I am referring to hand-rearing that included Abundance Weaning™ and a full fledging experience, at a minimum.) Further, if the previous home had included elements of deprivation, these individuals literally blossom when placed once again into more benevolent circumstances.

Further, I see behavioral similarities among the population of parrots who were weaned according to artificial time frames and whose wings were clipped before they ever learned to fly. These include dependent and sexually-oriented behavior toward one person, a lack of foraging ability, and fearful behavior that is inappropriate to the environmental context. I see these birds as permanently impaired and destined to a long existence in captivity that includes significant levels of stress. Often, the consulting process can improve their quality of life, but they will never be the birds that they would have been had they enjoyed a better beginning.

Chris’ blog post generated many comments on my Facebook page and a respectful discussion took place, although participants embrace many strongly-held and widely-divergent opinions. One breeder shared that she chooses to incubator-hatch her parrot eggs so that she can avoid the stress to the parents of having their babies repeatedly removed. Another disagreed with this approach because of the proven detrimental effects that accrue when babies are not allowed contact with their parents. My gratitude goes out to all who participated. Chris Shank, in various episodes of her guest blog, has brought to our attention the necessary components to successful parent-rearing. However, she herself questions whether the time frames for taming and training the babies produced this way are realistic when breeding for the pet trade.

Co-parenting seems to be a more viable answer. This is the process during which babies remain with their parents, thus receiving all the benefits of a parent-reared bird, but also have regular positive contact with people for both play and supplemental feeding. For this to be a viable approach, however, the parent birds must themselves be friendly enough toward humans. However, finding breeders who co-parent is next to impossible. Further, at this stage, just trying to find a breeder who is knowledgeable about behavior, practices Abundance Weaning, and fledges her babies is also next to impossible. I know this first-hand. Over the past two years, I have had several clients ask me to help them find a good breeder. We determine the species that they prefer to adopt and identify the geographical areas they can consider. We then identify potential breeders and I provide to the client a list of questions to ask the breeder to determine whether she really is a viable candidate. We then evaluate the answers together. Initially, I believed that to be an approach designed to ensure success.

I had a total of seven such experiences in the past two years and not one of them turned out satisfactorily. We found breeders who talked the talk, but that was as far as it went. One breeder agreed to fledge the baby parrot, but then clipped the wings without telling my client beforehand. She later explained that she was afraid the baby would hurt himself. She had said that she fledges her babies, but in the end clearly knew nothing about the process and did not understand the value. Another breeder was unable to support the baby into becoming food independent and finally insisted that the owner come and adopt her unweaned baby parrot. (This bird was well past the age when independent eating skills could be expected.) These experiences should never happen; yet, they are the norm.

The solution? If you really love parrots, then vote with your dollars. Simply refuse to purchase unweaned babies. Don’t purchase babies who can’t fly because their wings were clipped before they ever had a chance to fledge. Don’t purchase a baby who is “weaned” at an age before they would have fledged in the wild. Don’t purchase a baby whose early beginnings are going to commit him to a life of dependence, fear, and behavior problems. Educate yourselves and then drive this market toward improvement. We don’t want family members that have been reared by “farming industry practices.” That is the answer. You are the answer.

That will be solution enough until we can figure out an even better way of rearing baby parrots…until breeders realize that the market is demanding higher standards of them. My hope is that we will see a great deal more co-parenting and parent-rearing.

And in the meantime, consider seriously adopting an older parrot who needs a home. I can assure you that adopting a baby is no insurance policy against having behavior issues. All parrots will present you with challenges. There are so many adult parrots who need homes. If they come with problems, then get an experienced behavior consultant to help you. Problems can be solved!

Let’s keep this discussion alive, so that another 26 years doesn’t slip between our fingers, characterized by a lack of awareness and change. Captive parrots deserve better from us.

Addendum: If you are a breeder who co-parents or parent-rears and sends babies home fully-flighted, I would love to hear from you: pamelaclarkcvt@gmail.com.

Pamela Clark’s References  (click on link and scroll down)

Appendix IV: Position: Hand-Feeding: World Parrot Trust

Article by:  Jeannine Miesle, M.A., M.Ed

Main Article: Hand-raised or Parent-raised: Which Is Better For The Birds? by Jeannine Miesle M.A., M.Ed.

Appendix IV: Position: Hand-Feeding: World Parrot Trust

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Article and images courtesy World Parrot Trust; used with permission. https://www.parrots.org/about-wpt/position-hand-feeding, http://www.echobonaire.org/

One of the emerging and recurrent debates in parrot keeping is the question of whether to hand-feed baby parrots or to let the parent birds raise their chicks. Some claim that hand-feeding a young parrot will lead to a happier pet bird which is more tame and more strongly bonded with its owner. Others have asserted that allowing the parents to raise their own young will produce healthier and better-adjusted birds, which themselves will make better parents later in life. Not surprisingly, there is some truth to both assertions, and of course there are exceptions to every rule.

In principle, the World Parrot Trust supports husbandry choices for parrots which most closely reflect what these birds have experienced through millions of years of evolution. In the case of feeding baby parrots, with a few important caveats, their own parents are uniquely qualified for the job.

The importance of parental nurturing

If you ever get the privilege to watch the process in person you will find there is a lot more going on inside a parrot nest than just the deposit of food from adult to chick. There are complex interactions between the chick and its mother and father, and of course, for most parrots, among siblings as well. In the wild, these interactions go even further to include insects in the nest litter, or bats hanging from the top of the cavity, and other animals coming and going from the cavity. In one of our studies of a Caribbean Amazon, a nest camera revealed a chick perched happily on the end of an iguana’s tail!

Based on what we know about the development of other complex, intelligent, and slow-to-mature species, these early experiences, particularly relations with parents and siblings, are likely to be very important to the healthy development and successful fledging of the chicks. It’s nearly impossible for a hand-rearer to mimic such complex interactions throughout the day and night, whereas a parrot parent will very often do an outstanding job (particularly, it turns out, if it was too were raised by its own parents).

The positives of hand-rearing

Like nearly everything else with parrots, the reality isn’t so black-and-white. In the case of hand-rearing, there are of course instances when one or both parents, for whatever reason, choose not to rear their chicks, or make parenting decisions which threaten the chicks’ survival. Or in some cases, one of the parents is unable to care for the young. In these instances, very often it becomes essential for the chicks to be pulled from the nest and hand-fed, or left in the nest and given supplementary feeding. There is ample evidence that such birds, particularly if socialized well through fledging and independence, can grow to be happy and healthy parrots.

One final detail worth thinking about regardless of whether a parrot is hand-reared or parent-reared is that for nearly all parrot species, companion birds will consume a diet which bears only the faintest resemblance to what birds of the same species would eat in the wild. While of course this matters from a nutritional standpoint, there are other issues as well. One has to do with the phenomenally complex chemistry of wild tree seeds, fruits, buds, and bark, and the other has to do with their structure. Studies of wild parrots which sample the foods in chicks’ crops generally find a complex and coarse collection of ingredients – whole seeds with hard shells, insects, bark, soil, and other contents, none of which one is likely to find in a companion chick’s crop whether it’s fed by a human or its parent. In light of this, not only should parrot parents rear their chicks whenever possible, caregivers should be providing the adult parrots with as diverse and complex a collection of foods as they can manage, which will enable the parents the choice to feed their chicks the best possible combination of foods.

In sum, a parrot is the best parent for a parrot youngster.

Physical Illnesses & Conditions Brought About by Improper Hand-feeding

Article by:  Jeannine Miesle, M.A., M.Ed

Main Article: Hand-raised or Parent-raised: Which Is Better For The Birds? by Jeannine Miesle M.A., M.Ed.

Physical Illnesses and Conditions Brought About by Improper Hand-feeding

16.1 Beak Deformities from Poor Hand-feeding Techniques
16.1.1 Maxillary Brachygnathism
16.1.2 Mandibular Prognathism
16.1.3 Scissors Beak
16.2. Damage to the Crop
16.2.1 Crop Stasis—a Case Study
16.2.2 Crop Burns
16.2.3 Trauma to the Crop Caused by Improper Handling

Image 17: This breeder is correctly hand-feeding a chick; however, one can see how easy it would be for someone not experienced to cause beak trauma (image courtesy Thaddeus Tumanen; used with permission).

16.1 Beak Deformities from Poor Hand-feeding Techniques

Many people think they can hand-raise baby birds when they have had no experience or education from an experienced breeder on how to do this. They unintentionally harm the bird’s mouth, feet, and beak, and sometimes the deformities cannot be undone.

Hand-feeding techniques are a common cause of beak deformities. Brian Speer explains this:: “Incorrect incubation and/or hand feeding practices may be the more common causative factors, but the specifics of what those deficits may be are poorly understood. It is theorized by many that bruising of the rictal phalanges (the upper rictal area is where the beak meets the cere, and the lower rictal phalanges are where the under part of the beak meets the skin.) occurs during hand-feeding. There are feather bristles in these areas; damage to one side or the other leads to uneven growth, and most likely results in a scissoring deformity. Hand-feeding technique flaws resulting in bruising of the rictal phalanges, incubation flaws, genetic etiologies, sub-clinical malnutrition, infectious sinusitis, trauma and viral disease have all been suggested as possible contributing causes. Corrective procedures in young birds are designed to alter the forces that direct the rostral growth of the rhinotheca.” 10

Image 18: Anatomy of the beak (image courtesy PetEducation.com; used with permission).

• The rhinotheca is the outer surface of the beak. It is composed of a horny layer of keratin which covers the beak.
• The rhampotheca is the layer of keratin on the maxilla (upper beak). The gnathotheca is the layer on the mandible (lower beak).
• The commissure is the soft tissue at the back of the beak where the two parts meet. It is composed of soft tissue for the opening and closing of the beak to take place.
• The rictal phalanges are the areas of the beak just below the commissure where the maxilla and mandible meet. There are usually bristle feathers in that area.
• Tomia: cutting edges of the beak
• Malocclusion (poor closure of the beak) is a consequence of trauma due to damage to the germinative layer of the beak, improper hand feeding, poor nutrition, or heredity. The practitioner may be able to use composite or acrylic materials to shape the beak properly and encourage normal growth following trauma. 7

16.1.1 Maxillary Brachygnathism

This is one condition that is sometimes caused by improper hand-feeding. With it, the maxilla extends well past the mandible. It is usually a congenital condition, and cockatoos are most frequently affected species. It is most often caused by trauma which damages the germinal epithelium of the beak. “Young birds with this condition are often more receptive to having this condition corrected since their beaks are more pliable than adults’ beaks. Wiring or prostheses may be used to gently put the beak back in alignment.” 7

Image 19: Maxillary brachygnathism, or overgrown beak, in an Amazon (image courtesy Dan Razdik; used with permission).

Image 20: Mandibular prognathism, or maxilla inside mandible, in a cockatoo (image courtesy Melanie Canatella; used with permission)

16.1.2 Mandibular Prognathism

This is another recognized pediatric condition sometimes caused by improper hand feeding. With this, the maxilla lies inside of the mandible, and it is most often observed in cockatoos. One technique which has been used to correction this deformity has been the application of acrylic to the maxilla. This technique “functionally extends the maxilla, making it more challenging for it to be placed inside of the mandible, and guides occlusion (closure of the beak) properly. Typically, when the acrylic loosens and comes off in 1-2 weeks, the problem is corrected.” 10

16.1.3 Scissors Beak

Young, hand-fed cockatoos and macaws are frequently afflicted with scissors beak. “Scissors beak deformities are characterized by a bending of the upper beak rhinothecal keratin and/or bone to one side to varying degrees, with the resultant overgrowth of the opposing lower gnathotheca. As force vectors are applied during the bird’s growth and regular use of its beak, this deformity usually will become progressive, ultimately generating a ‘scissors’ effect.’ In addition, secondary deformities of the occlusal ledge of the rhinothecal keratin may develop.” 4 “The occlusal edge is the underside of the maxilla or upper beak where it meets the mandible or lower beak; it acts as an anvil by which the bird can crush nuts and seeds and other foods.” (R. Dahlhausen, personal communication) “This deformity carries a significant impact on the salability and potential breeding performance of the birds.” 10

Due to the stress put on the bird from trying to eat and perform the usual beak grinding, an increase in the fear-based behavioral problems will occur. The owner should be encouraged to consider having these conditions surgically corrected. “The corrective techniques that are available today are vastly superior than in the past and are worth considering when one takes into account the quality of life and long-life expectancies of the larger species.” 10

Scissors-beak is most commonly seen in macaws, and the trans-sinus pinning technique as well as others are being used to correct this deformity. Application of corrective techniques for both conditions have been limited to use in young birds since they have not been successful in correcting these deformities in adult birds. 10 In adults, the beaks must be constantly trimmed and reshaped in order for the bird to be able to eat.

Images 21 and 22: Scissors beak in a cockatiel (image courtesy Dr. Maria Angela Panelli Marchio; used with permission).

16.2. Damage to the Crop

16.2.1 Crop Stasis—a Case Study

A twelve-week-old blue and gold macaw was presented with a history of crop stasis of 24 hours duration. The bird had been purchased from a breeder in Georgia at the age of 6 weeks. The baby had been parent-fed for the first four weeks of its life and then switched to a commercial hand-feeding formula. On physical examination, the bird was bright, alert, and responsive and had a brisk feeding response. It was well grown for its age and was completely feathered. However, the crop was still full from the feeding the night before and the bird was mildly dehydrated, slightly thin, and there were many stress bars on the growing feathers. Gram’s stains of the crop showed budding yeasts and Gram-negative rod-shaped bacteria. “A Gram stain of a cloaca swab showed moderate numbers of Gram positive coccoid and large rod-shaped bacteria.” 8 The white blood cell count was normal, but radiographs showed a distended proventriculus. A fecal float and direct smear were negative for parasites. 8

This was a case of crop stasis that in nestlings can have any number of causes, “ranging from improper husbandry to systemic infectious diseases.” 8 It is not normal for fledglings to develop crop stasis, and it appeared that this bird had been under a great deal of stress for several days, as evidenced by the number of the stress bars on his newly formed feathers. 8 The bird had not been digesting its food very well, and it resulted in an overgrowth of yeasts and bacteria in the crop. Some birds will develop distention of the proventriculus, but that also might be a sign of a primary disease of the gastrointestinal tract which affects motility. 8

16.2.2 Crop Burns

Crop burns that lead to fistulation normally occur in unweaned psittacines fed formulas that are too hot. Microwaving formula is often the cause due to uneven heating. Damage to the crop may interfere with crop motility. Mild burns may cause inflammation and edema that may resolve. Extreme heat may cause a fistula (a hole leading to the outside) into subcutaneous space or a full-thickness fistula. 1

Birds will present with voracious appetite and weight loss. On physical examination, moistened feathers are noted in the area of the crop; normally a scab is present. It is recommended to wait 3-‐5 days in the case of full-thickness fistula. The tissue needs time to show the extent of the damage, otherwise repair may fail. Extensive burns require removal of an extensive area of the crop; prognosis may be poor due to lack of normal function. 1

Images 23. African Grey: Crop burn from hand-feeding with formula that was too hot from being heated in a microwave. A large fistula was present and needed to be repaired surgically (image courtesy Aswathy Sathi; used with permission).

When the crop is burned or traumatized, there may be loss of significant portions of tissue. In some birds there will be a true fistula with food dropping out. In more acute burns, it may be difficult to distinguish viable from devitalized tissues. In these cases it is best to wait 3-5 days for a line of demarcation between necrotic and viable tissue to develop. The wound edges should be debrided until the skin can be separated from the crop wall. The skin and crop are sutured closed as separate structures. Placing a feeding tube through the crop will help identify the lumen. “In cases where there is significant loss of crop tissue, it is best to maintain the longitudinal integrity of the esophagus (crop) as there is a higher likelihood of stricture formation with resection and anastomosis.” 1,3 (Anastomosis a connection made surgically between adjacent blood vessels, parts of the intestine, or other channels of the body, or the operation in which this is constructed (Wikipedia).

16.2.3 Trauma to the Crop Caused by Improper Handling

Laceration of the esophagus can occur following the use of a rigid feeding tube. 7 The ingluvies refers to the crop, an outpouching and storage area in the esophagus that is often full and protruding, making it susceptible to trauma. It may also be the site where a foreign body has lodged. 1

Image 24: Full-thickness crop burn in an umbrella cockatoo. The scab is being pulled away to reveal the large fistula from which formula is leaking out (image courtesy Scott McDonald; used with permission).

Image 25: The umbrella cockatoo after crop-burn repair. The crop and skin are closed in separate layers after unhealthy tissue from wound edges is trimmed away (image courtesy Scott McDonald; used with permission). http://scottemcdonald.com/pdfs/Crop%20Disorders.pdf

Pet Birds: Hand-raised or Parent-raised: Behavioral Issues Associated with Hand-reared Chicks

Article by:  Jeannine Miesle, M.A., M.Ed

Main Article: Hand-raised or Parent-raised: Which Is Better For The Birds? by Jeannine Miesle M.A., M.Ed.

10. Behavioral Issues Associated with Hand-reared Chicks

So what are the consequences of hand-raising chicks? Because these birds were raised in an unnatural manner, they “never developed an appropriate sense of self.” 2 Pulling the eggs, artificially incubating them, and hand-feeding the chicks result in birds which have imprinted on humans instead of other birds. Even if they are allowed a few weeks in the nest before being pulled, the result is almost the same. The imprinting is not quite the same as it is with the artificially incubated chicks, but very close. Consequently, these birds “often have a human self-orientation, leading to the development of an abnormal human‐bird bond.” 2

10.1 Aberrant Behavior Involving Developmental Skills

According to A. Gallagher, There is a specific window of time during which birds learn initial, social developmental skills. They are learning how to be birds from other birds in the nest during this time. If this learning time is not permitted, and is instead replaced with abnormal human self-identification, it is essentially impossible to reverse. This bond produces many undesirable behaviors:

• “Separation anxiety. The new human family becomes the bird’s flock. The bird does not understand why the flock leaves it alone all day, defenseless. If this were a wild scenario, a lone bird would be defenseless against a predator. This situation causes severe anxieties for many companion birds. 2
• “Aggression. The new owners generally have no real understanding of the techniques required to discipline or train their bird as would naturally occur in the flock situation. This is why you will hear of many birds becoming ‘feral’ and aggressive after being cuddly babies. 2
• Sexually-fueled separation anxiety. Before maturity, the bird will choose a mate from the human flock. The bird has the same expectations as the wild-breeding pairs. The bird expects to never be more than a few yards from its breeding mate. It does not understand the need for us to enter another room without it, go to work or leave for holidays. Again, extreme separation anxiety and neurotic behaviors occur, resulting in screaming, feather plucking and self-mutilation, stereotypic behaviors, nervous tics, aggression, and destructive behaviors. 2
• “Mate aggression. The bird will adore one family member (its breeding mate) but attack all others who come close. 2:  (Aviaweb Note: Also refer Breeding Mate Aggression / aggressive behavior towards a breeding partner.)
• Territorial aggression. These birds will defend their cage from other flock members, biting anyone who ventures too near the nest site (cage). Often birds will develop a predilection for other sites around the house for nesting and defense, e.g. behind kitchen appliances, in drawers, behind cushions, under beds or other furniture, even inside the owner’s clothes while being worn! 2
• “Sexual frustration. Aggression is usually a result of failure on the part of the human to provide gratification. The human is the “chosen one,” the mate they want to reproduce with. When you pet and love on her, that’s foreplay to a bird who doesn’t have another bird for a mate. When the attention you give the bird doesn’t result in continuing the natural progression to breeding, she is frustrated and takes her anger out on the “chosen person” for not finishing what he/she started. The frustration can be huge, and the bird will often turn on herself or himself to relieve the frustration. Because hand-fed birds are abnormally attached to the chosen person, they will scream, self-mutilate, attack, masturbate, and lay eggs more than parent-raised birds. 2
• “Excessive egg production. Female birds (hens) breed as a result of several external factors. The primary factors are generally long day lengths, a high-energy, high-calorie diet, frequent bathing, a stable mate, and nesting environment. Birds with an abnormal human‐bird bond, kept under artificial light after dusk and on a seed-based diet, have all the prerequisites for egg-laying. These birds generally lay large numbers of eggs. “This excess production has a dramatic impact of the hen’s nutritional status and often results in osteopenia (low bone density leading to osteoporosis), cloacal prolapses, fractures, and reproductive complications. When laying, most birds will display territorial aggression around the nest site.” 2

Some owners attempt to relieve the bird’s anxiety by obtaining another bird, but often neither bird has the skills needed for social interaction, so “they often appear to live like ‘two lamps on a shelf’ with no recognition of each other.” 2 Once this abnormal human-bird bond develops and problem behaviors begin, it is very difficult to completely eliminate them, but these behaviors can be modified with education and training. 2

Pamela Clark’s Blog, Early Beginnings for Parrots, Appendix  III 

10.2 The Connection between Hand-Rearing, Aberrant Behaviors, and Health Issues in Specific Species

There is evidence of a pathological connection between hand-rearing and aberrant behavior in adult companion birds. Any species may exhibit these unwanted behaviors, but the groups in which these are most often seen are the cockatoos, Amazons, and to a somewhat lesser extent, macaws. Behavioral disorders are most frequently encountered in the larger psittacine species, although they can be found in the smaller species as well. And although physical health issues are more commonly seen in the smaller species, such as the cockatiel, budgerigar and parrotlets as a result of hand-rearing, they may be found in the larger species as well. 2

10.3 Differences in Behavioral Development toward Novel Objects

Parental separation and hand-rearing affect the development of other behaviors. When first introduced to new objects, hand-raised birds did not display as much fear as parent-raised birds. However, this fear was only postponed. By the time the birds were a year old, both hand-reared and parent-reared birds, housed under similar conditions after weaning, reacted in the same way after being exposed to new objects. It’s possible that delayed maturation or “generalized exposure to new items” played a part in the difference. 12 Birds become less fearful of new things in their environment, indicating that they are sensitive to changes for quite a while after weaning; then they gradually adapt to new environmental conditions. “In the wild, this may aid them in decreasing the risks of predation or ingestion of toxic materials. It also may increase the chances that they’ll find new foraging sites, nest sites, or mates.” 12

As a result, parrots that dwell in frequently changing environments tend to be less fearful of new situations and objects than those that inhabit relatively constant, predictable environments. Birds in captivity display the same behaviors. When young birds are exposed to items that are new or frequently rotated and environments that are diverse, they have less fear of new places or objects. These findings emphasize the importance of regular rotation of toys and other enrichments; simply providing the enrichments and leaving them indefinitely is not stimulating for the bird. There must be frequent changes in their environments. However, we must be very careful when presenting new objects or housing to fearful birds; too many changes too close together can intensify the fearful behaviors. “Individual differences in reactivity to novel experiences must always be considered when providing enrichment opportunities or new environments to birds.” 12

Image 10A: This hand-raised African grey parrot on the left (Psittacus erithacus) was presented with a novel object, a child’s teething toy in the shape of a monkey. Although the bird did not panic, it was reluctant to approach this new toy. The reluctance to approach a novel object is referred to as “neophobia” (image courtesy Yvonne Van Zeeland, in Speer: Current Therapy in Avian Medicine and Surgery).:

Image 10B: This parent-raised African grey parrot (Psittacus erithacus) was presented with the same novel object as the parrot in Figure 6- A. Despite the fact that this bird had also never been in contact with the toy, it immediately approached this new toy and started to explore it with its beak and feet (image courtesy Yvonne Van Zeeland in Speer: Current Therapy in Avian Medicine and Surgery).

10.4 Abnormal Sexual Behaviors in Hand-reared Birds.

Hand-raised birds are also more prone to develop abnormal sexual behaviors toward humans. These include regurgitation, masturbation, courtship behavior, territorial aggression, sudden onset of phobic behaviors, excessive vocalizations, continued begging and whining for food (including delayed weaning), and feather-damaging behavior. “Many of these abnormal behaviors may develop as a result of frustration (e.g., inability to sexually bond with humans) or to seek attention from the caregiver. As such, they appear similar to the “orphanage syndrome” or “relative-attachment disorder” described in human children who have been deprived of affection and stability in their early childhood.” 12 Birds that are hand-reared are deprived of the necessary contact with other birds of the same species as well as with their parents and siblings. This contact with conspecifics is needed to establish normal social and sexual behaviors. 12

Image 11: Loving parents feeding their baby (image courtesy Alona Samorodska; used with permission).

Image 12: Three of this pair’s chicks at 3 weeks (image courtesy Alona Samorodska; used with permission).

Comments from “The Science of Avian Health” Members and Breeders

Article by:  Jeannine Miesle, M.A., M.Ed

Main Article: Hand-raised or Parent-raised: Which Is Better For The Birds? by Jeannine Miesle M.A., M.Ed.

Appendix II: Comments from “The Science of Avian Health” Members and Breeders

Member 1: Well said. It would be good for you to post this on the African Grey Parrot Asian Forum. I find it heartbreaking the amount of breeding that’s going on and chicks being sold at a few weeks old to people who don’t know the first thing about hand feeding let alone looking after a young bird.

My boy was co-raised by both parents and the breeder. He was fully fledged at 12 weeks old and a handful then. He’s still a handful but a very independent handful. He is not bothered by changes in routine and eats just about anything I give him.

My first bird is the same. He wasn’t taken away from the parents for about 10 weeks and then he was weaned by the breeder for a couple of weeks. He too was a handful but he is so adventurous, brave, and inquisitive, he really knows how to play and have a great time and accepts change easily. In fact he seems to relish change and sees it as a new adventure. It is so rewarding to see a bird display ‘bird’ behavior rather than a modified behavior because they haven’t spent time with parents and siblings like many hand-reared birds.

Yes, mine is like yours. He enjoys new people and is friendly with them. He’s not a cuddly bird by any means but likes your company. He flies like a jet plane around the house every morning then settles down to have his breakfast while I read the paper. He eats beside me every day. He even asks to go outside in his aviary that’s just like Morgan and my other one, Flint; they were both parent reared. They say to me, “Do you want to go outside?” in such a sweet voice when they want to go in the aviary. We are so lucky to have such independent birds. Mine are not as cuddly as some birds I see but they fly to me, and I have no problems with them stepping up. I am just so happy that they are birds and not pets. (No offense meant to anyone else or any other bird, I know we all love our birds.

I remember getting into a very heated argument with one of my former investors about this very subject, swearing I was somehow cheating the customer. It has been my experience through hands-on work that baby parrots that are raised by their parents are healthier, easier to train, have better plumage and behavior. I’ve raised hundreds of conures, and every single hand-fed chick has turned into a screamer or has some sort of anxiety problem. On the other side of things, almost every parent-raised conure has been quieter and more calm (as a conure can be) and relaxed in day-to-day life. I’ve noticed this in cockatiels and Ringnecks as well.

Member 2: “I got her from a breeder and yes, she was hand-raised but not with a caring hand. This guy is a huge breeder and has birds of ever kind, so it’s more of a feed-and-go. So she isn’t very tame because no one ever spend time with her.” It’s not just the feeding that counts, it’s the interaction and loving environment that’s important. This is a good case for not hand-feeding. Birds that are parent-raised and given a lot of human interaction and love will turn out to be caring, loving adults, no matter how their fed. (Kim Martin; used with permission)

Member 3: I have recently had two clutches of baby budgies hatch at the same time. I lifted one clutch at the usual three weeks mark and with the other clutch just handled them every day (as often as I could through the day). I have to say I don’t actually see a difference in the friendliness of them, but I must admit the transition to ‘hard’ food appeared easier with the parent-raised babies. Whilst dependent on being fed for survival, the babies that were co-parented appear cuddlier, seeking the contact for reasons other than food. The hand-raised babies initially only want the contact for food. I still enjoy feeding the babies but now share the load with the parents. (Clair Bear; used with permission)

Member 4:

· There are times when hand-rearing is the only way to save a baby.

· Co-parenting should become standard in avian production,

· Abundance-weaning and full-fledging are crucial to the emotional and physical development of the birds.

· Forced-weaning and early clipping are cruel practices that damage the mental physical, and emotional health of parrots..

· Although there are some species in which co-parenting may not always be successful, every effort should be made to do so because of the benefits to the birds.

· Bird mills do not want to parent-raise because it will decrease their production, but they are producing inferior-quality birds; this is why many of them do not live long, are often sick, have birth defects, and don’t breed as well as parent-raised birds.

Member 5: “The chicks I hand-raised were much friendlier than those that were parent-raised without any human interaction. However, I did it for the love of birds and never raised more than I had time for. It took a lot of time and commitment to make sure that each chick got enough attention. I would spend the evenings playing with them – and that is what I enjoyed so much. There is no way anyone can do that if they have hundreds of birds.

What I have noticed is that many breeders who hand-raise chicks don’t put any time in other than forcing food down the crop using a crop needle. That, and cleaning up, was all the chicks ever got to do with the human caretaker. That will not result in tame adults. Hand-raised birds will never have experienced the nurturing of parent-raised birds. And since the chicks never experienced parenting , so many of them became bad breeders later. So – really – there was no point in denying chicks the nurturing care of their natural parents and denying their parents the joy and right to raise their own chicks.

Once I noticed that, I left the chicks with the parents to raise, but took them out every day for half an hour or so to get them used to humans. That worked well. Half an hour per chick sounds like a lot of time; but I used to sit on the couch with them and have all the chicks out on a blanket at the same time playing with them (or split them up in groups), and that worked well. Of course, this will never be possible for large aviaries, and that is the reason why the vast majority of “hand-raised” chicks available in stores aren’t really tame

I don’t like the crop needle that many breeders use because it is too fast. I understand its use if chicks or adults are too sick to feed, but that is all I would feel comfortable with.

I do believe that for the emotional and physical health of our captive birds, allowing them to be raised by their natural parents, but pulling chicks for at least half an hour a day for socialization, gives the chicks the best start in life. The only valid reason for pulling chicks out of the nest is if they are abused by their parents. That point alone brings us back to the very gist of this matter.

Many of the captive birds that have been “hand-raised” by humans have never been able to experience natural parenting, and many of them don’t know what they are doing when they become of breeding age. Some of them will figure it out over time; however, many of them never will and should be taken out of the breeding program as they will consistently damage their eggs (even eat them) or abuse their chicks (including killing them). In this case, pulling eggs or chicks out of the nest is necessary to save them. (Author’s note: If the parents had been allowed to raise their chicks from the start, they would likely not be damaging the eggs or chicks.JM)

Member 7:

I guess it’s a controversial topic amongst psittacine owners, but from the perspective of someone at high volume wild bird clinic, I simply cannot fathom why anyone would choose to separate a parent and its baby, barring abnormal/emergency type of situations that would warrant it.

Robbing a young baby from its parents is absolutely not a hard requirement for a “humanized” bird.

In my line of work, I see approximately 2,000 fledgling songbirds a year that are inadvertently kidnapped from their parents. The parents mourn these babies… the babies get depressed and sad… many die, crying weakly in vain for their parents. It’s heartbreaking.

To echo what’s been said above, certainly logic and a compassionate heart should tell us that the natural parenting method should be the first choice as much as feasible.

Member 8

The best babyhood is with its parents until it is fledged and weaned… it’s such a non-issue that they cannot be tamed at a later age. I have a 30 year old former naturalized, wild, born and raised macaw that is retired from his wild life due to sickness. He is a sweet heart and even better, he is calm, can deal with stress and he knows he’s a bird so no crazy behavior. We did some years of study on his life when he was still living wild together with a partner and his nests were poached almost every year. The utter heart break they experienced when their young were gone was such a heartbreak. They would search and call out for them for days. It’s beyond me how one would like to make a living with this as your business strategy while all rescues are filled to the brim.

Member 9.

Agree with your points 100%. I think most people grossly underestimate the emotional capabilities of birds.

I recently assisted the federal Fish and Wildlife Service with charging a couple for trapping wild house finches and selling them as pets on Craigslist. The people had successfully sold at least 2 dozen or so, but we were able to confiscate about half a dozen that they had.

Member 10: House finches have very close familiar bonds; they mate for life and are the most diligent animal parents I have ever seen, ever. They will even adopt babies that they know aren’t theirs.

When it came time to release the confiscated birds, I filmed some of the release. I was hoping maybe it would make for moving footage, seeing a trapped wild bird set free, but it was actually very very sad.

Each of the releases birds, upon being let out, perched on a nearby branch, and proceeded to call out for their mate. Of course, the trappers didn’t trap any mates together, so they were all separated from their respective partners.

When they realized they were outside again, which is where their mate last had been, they all began frantically calling and looking.

Weeks later, these birds are still looking and calling for their mates.

The birds are having no problem with survival, since they were born and raised outside, and they’ve joined a flock of conspecifics, but there is no question that they are depressed and heartbroken. I wish more people understood these aspects..

Author: People think they have no feelings, no emotions. But that is far from correct. They are sensient beings, with feelings that can be hurt very easily. In my research for this paper, I found that many pairs refuse to mate and lay eggs because of constant removal of the eggs or chicks. I don’t blame them.

Member 11: I would like to see this posted in every bird group. I don’t say anything because I get attacked if I do, but I don’t support human raised birds when the parents are there and doing a good job. And when I hear of a baby sold to someone WHO HAS NO IDEA HOW TO FEED THAT BABY I get angry, then sad knowing the probable outcome for the bird. I blame the breeders who do this for doing more harm than good to that baby and know they aren’t a breeder I’d ever buy from. The should be shamed but I’m quite aware standing up for the birds gets you blocked or in fb jail and that is extremely sad.

Member 12: I had a finch that the parents would not feed and I was afraid he would die. So i started hand feeding him until I could see him gaining weight and looking healthier. Once that happened I put him in with my societies and he became so attached to them he stayed and I lost a potential hand reared friend. But he needed to be with his kind.

Member 13: Great article. My CAG Poppy was allowed to remain in a more natural environment by her breeder. We did get to meet her several times before we were allowed to bring her home. I didn’t realize at the time how exceptional her breeder really was. Thank you for advocating for our precious birds.

Member 14: This is absolutely the best thing I have read so far. If only I could get them here to understand. All they do is hand feed pull the babies as soon as possible from the parents so that they will lay more and they can make more money.

Author: I’ve read about breeders that just feed them and leave, not spending any time socializing them to humans. Now they have nothing; no parents and siblings to learn to be birds from and no human interaction.

Member 15: This is mind blowing. When I have my parrot he’s only 5 months old. He didn’t know how to play with toys, he didn’t know how to interact with other birds, he still doesn’t. I was very stressed about that and didn’t even notice he might be more stressed. He is still very needy. After reading this everything makes more sense.

Second-and third-hand smoke are the most common causes of tobacco-related diseases; however, other forms of tobacco and nicotine products cause damage as well – damage that includes injury to the cardiovascular system, respiratory system, feathers, integument, and gastrointestinal system.

Unless the disease is too advanced, removal of the bird from the toxic environment, along with medical management, will usually result in a resolution of the clinical signs and healing of damaged tissue.

Introduction

Human beings have known of the dangers of smoking for hundreds of years. To deny the health risks posed by tobacco products is absurd.

A century ago, people were giving cigarettes the term, “coffin nails,” and for decades, health care providers have been attempting to warn their clients that they are jeopardizing their own well-being by inhaling or otherwise taking in the harmful by-products of nicotine.

If tobacco products are harmful to humans, with strong hearts and lungs, how much more detrimental are they to birds, which have extremely delicate circulatory, respiratory, pulmonary and integumentary systems?

Chronic illnesses abound: upper respiratory infection, coughing, sneezing, sinusitis, conjunctivitis, just to name a few. Secondary bacterial infections are common, and many of these illnesses can prove fatal.

The more the bird inhales the cigarette, cigar, or pipe smoke, or is handled by a smoker, the more his ability to tolerate the damaging effects of the tobacco products decreases.

However, removing the bird from a second-hand smoking environment, along with proper medical management, can result in the return of the bird to health if caught in time.

The Avian Respiratory System

Birds and other exotic animals have extremely sensitive respiratory systems.

Mammals’ lungs are strong and sturdy and are able to perform all the tasks necessary for breathing. But birds have small, fragile lungs, and their air sacs do most of the respiratory work.

Also, their lungs do not function as ours do; they are attached to the back bones, and so they do not expand and contract in the same way ours do. ²

1.1 Avian Air Sacs

Most birds have 9 air sacs throughout their bodies:

• One interclavicular sac
• Two cervical sacs
• Two anterior thoracic sacs
• Two posterior thoracic sacs
• Two abdominal sacs ²

“Air sacs and axial pneumatization in an extant avian. The body of the bird in left lateral view, showing the cervical (C), interclavicular (I), anterior thoracic (AT), posterior thoracic (PT), and abdominal (AB) air sacs.

The hatched area shows the volume change during exhalation. The cervical and anterior thoracic vertebrae are pneumatized by diverticulae of the cervical air sacs.

The posterior thoracic vertebrae and synsacrum are pneumatized by the abdominal air sacs in most taxa. Diverticulae of the abdominal air sacs usually invade the vertebral column at several points.

Diverticulae often unite when they come into contact, producing a system of continuous vertebral airways extending from the third cervical vertebra to the end of the synsacrum.” ¹⁷

Key Facts About Avian Lungs And Air Sacs

When birds breathe, two inhalations and exhalations are required to completely change

the air in the air sacs. It takes two breaths to complete a single respiration cycle and move air through the entire respiratory system. The second breath pushes the first through to the end of its cycle.

Most birds have 9 air sacs (some have 7) which extend into specific hollow bones. This makes them lightweight and enables flight.

The vertebrae are divided into two sections: The upper section is called the “notarium,” and the lower section is called the “synsacrum.” The bones of each are fused, but each section is able to move independently, thus enabling flight.

Air sacs have very thin walls with few blood vessels, so they do not directly control air exchange; instead, they act as bellows to ventilate the lungs.

The lungs are stationary; they are affixed to the bones of the spine, and they are not lobed like those of mammals.

Birds do not have a diaphragm. Air is drawn in and expelled by the contraction of muscles.

Because there is no diaphragm, and the air sacs extend into the bones, respiratory infections can also extend to the abdominal cavity and the pneumatized bones.

A bird’s respiration rate is slower than that of mammals of similar size, but its pulse rate and body temperature are higher.

The respiratory system of a bird is more efficient than ours in transferring oxygen; it readily extracts harmful gases and particles from inhaled air, increasing a bird’s sensitivity to inspired toxins.

Because of this efficiency, a parrot will succumb to the same level of toxic fumes that would be tolerated by a dog.

Birds cannot withstand inhalation of 100% oxygen for more than 12 hours. This treatment had been used, but was found to be fatal, with death occurring in four to eight days.

Exposed birds appeared stressed and uncomfortable as early as three days post-exposure. ^{2, 22}

2.1 Avian Respiration

Your parrot has a very different respiratory system than humans; birds have lungs, which are not lobed like our own.

They also have air sacs that extend into their bones and are hollow and lightweight; these enable them to fly. Air is drawn in and expelled by the contraction of muscles.

Because there is no diaphragm, and the air sacs extend into the bones, which means respiratory infections also can extend to the abdominal cavity and the bones.

Because the respiratory system of a bird is more efficient than ours in transferring oxygen, toxins inhaled are delivered equally as well. ²⁰

2.2 Movement Of Air Through The Air Sacs And Pneumatic Bones

Birds have nine air sacs and a syrinx (vocal center). Unlike mammals, they have no diaphragm, and there is a unidirectional airflow that requires two full inspiratory and expiratory cycles to complete.

Air enters through the nares, past the larynx and into the trachea (which has completely closed cartilaginous rings), past the syrinx at the bifurcation of the trachea into the bronchi.

Down the bronchi, the air enters the caudal air sacs (2 paired caudal thoracic and 2 paired abdominal air sacs) with a small amount bypassing directly towards the lungs.

At exhalation, the air is expelled from the caudal air sacs into the ventrobronchi and dorsobronchi and down continuously narrowing airways into the lungs where gas exchange takes place.

The exchange occurs in tubular air capillaries rather than saccular alveoli. The lungs are fixed anatomically and therefore do not expand or contract.

At the next inhalation, the air moves into the cranial air sacs (paired cranial thoracic, paired cervical and a single clavicular air sac). At the next exhalation the air is expelled through the trachea once again.

Since birds lack a diaphragm, the inhalation is achieved by expanding the chest, moving the ribs laterally, moving the sternum ventrally and cranially, and expanding the abdominal muscles. ⁷

2.3 Pneumatization

Air sacs are not limited to the individual balloon-like structures as seen in Figure 2; they also extend into the humerus (long) bones of the wings, some vertebrae and ribs, the femur bones, and even the skull.

These bones are then considered “pneumatized.” Only those bones are pneumatized; all others contain marrow. ¹⁷

Pneumatization occurs when “diverticulae,” (smaller sections of the air sacs), extend into the bones. Figure 3 shows a side view of the air sacs and pneumatized bones. The hatched area at the bottom depicts the volume change during exhalation. ²⁶

Pneumatic bones have air spaces in them; they’re structurally more like corrugated cardboard than solid bone. In birds, this system is “open” for air to move through, ²⁶

While most animals have just facial pneumatic bones, birds have them in their skulls and throughout their bodies.

These include their clavicle, humerus, keel, pelvic girdle, lumbar and sacral vertebrae. Attached to a bird’s lungs are eight or nine (up to eleven) air sacs; these are hollow, balloon-like sacs that hold air and act like bellows.

There are usually four or five around the front and underbelly of the bird and four at the back. These air sacs allow air to move one way, which is highly efficient.

Think about our breathing: It’s multi-directional, air goes in and air goes out the same way.

Old air mixes with new air and it’s pretty inefficient. In birds the air is moving around in one direction, and they’re always getting a “fresh breath of air” when they breathe in (no old air moving out past it and mixing). ²⁶

This is an excellent video on movement of respiratory system:

The cervical and anterior thoracic vertebrae are pneumatized by diverticulae of the cervical air sacs, which means that small sections of the air sacs extend into the bones (are diverted) into the upper spinal area. 17

The posterior thoracic vertebrae and synsacrum (the fused bones in the lower vertebrae of the back, see Figure 3) are pneumatized by the abdominal air sacs, meaning that small sections of the air sacs extend into the lower section of the backbones (the synsacrum).

Some diverticulae also enter the rib cage and skull. Diverticulae of the abdominal air sacs extend into the vertebral column at several points.

Diverticulae often unite when they come into contact, producing a system of continuous vertebral airways extending from the third cervical vertebra to the end of the synsacrum. ¹⁷

The function of this connection is thought to be that by having air sacs attached to the bones, their breath/air provides air pressure and strength to the skeleton, helps cool the bird by diffusing heated air, and helps the bird remain light for flight.

If you think about it, a bird is breathing through its lungs, air sacs, and bones all the time. ²⁶

3. Tobacco Toxicity In Birds

The extremely sensitive respiratory system of birds is affected by any form of air pollution. Second-hand and third-hand smoke are the most damaging.

Pet birds absorb nicotine and other chemicals through their skin and feathers. This can elevate their risk of developing lung cancer and a range of other conditions if they are exposed to second-hand smoke on a regular basis.

Most importantly, birds who live with smokers are prone to developing allergies, pneumonia, and chronic sinus trouble. ¹⁹

3.1 Signs Of Tobacco Toxicity Are:

“Signs develop quickly in most species, usually within 15 to 45 minutes, and many of the above signs develop. Death from nicotine toxicosis occurs secondary to respiratory paralysis.

A less serious but common response to cigarette smoke deposition on the feathers is feather-destructive behavior. One timneh grey that expired at 21 years of age reportedly had lived its entire life with a heavy smoker.

The histopathologic diagnosis of multiple masses in the lungs was carcinoma, but was not definitely labeled as bronchiogenic, (beginning in the bronchial tubes).” ²¹ Treatment is supportive and based on symptoms. ⁹

3.2 Nicotine Amounts In Tobacco Products

3.3 Nicotine Poisoning

Where there are smokers, there are nicotine products. Nicotine poisoning can occur when your bird finds and chews apart a cigarette like a shredder toy.

The butt of a cigarette alone contains 25% of the nicotine of the original cigarette.²⁰ Pets aren’t always picky about what they eat. This appetite can get the better of them if they make a meal of tobacco products.

Just a single cigarette may be enough to cause nicotine toxicity in a bird. Even discarded cigarette butts in ashtrays can poison pets with their small doses of potent nicotine. ¹⁹

3.4 Forms Of Tobacco-induced Toxicity Other Than Inhalation

Inhalation is not the only means of tobacco and nicotine absorption; animals may lick up toxic chemicals.

Nicotine, tar, and carcinogens may land on their fur or feathers after the smoke in the air settles, thus increasing their chances of developing cancer.

In addition, they may eat products containing nicotine, such as cigarettes, cigars, chewing tobacco, nicotine gums, and patches.

Nicotine is often used as an insecticide, so animals must not be allowed access to any such products or walk onto grass and other foliage that has been sprayed. ¹¹

4. Toxicity From Second-hand Smoke

The most common cause of tobacco-induced avian toxicity is second-hand smoke—the smoke that is exhaled from a smoker.

Primary respiratory disease and complications involving other systems of the body are caused by exposure to tobacco smoke.²⁹

Another name for second-hand smoke is “Environmental Tobacco Smoke” (ETS). It contains thousands of different chemicals that fill the air as either gases or particulates.²⁹

Even if the cigarette, pipe or cigar just sits burning in an ash tray, it also releases smoke and toxins from both the lit end and filtered end.

Thirty years of scientific research has proven that people constantly exposed to environmental tobacco smoke are more likely to develop and die from heart disease, lung cancer, and breathing illnesses.

Exposure to marijuana is also deadly for birds. ²⁹

To read more information on marijuana toxicity, see Appendix A, p. 35.

Smoke inhalation is just one source of potential health hazards for pets living with smokers. Dogs, cats, birds, and small pets are continually exposed to second- and third-hand tobacco throughout the day as they groom themselves and interact with their owners.

Birds are persnickety about personal hygiene too. ¹⁹ How much more likely are birds to developing these illnesses than cats and dogs.

4.1 Contents Of Second-hand Smoke

Second-hand smoke contains over 4000 chemicals, including 69 compounds that are known to cause cancer. Anyone who breathes second-hand smoke is breathing in

The concentration of these carcinogenic chemicals is actually higher in second-hand smoke than in the fumes directly inhaled by smokers. Their feathers will pick up the odor, and birds will try to rid themselves of it by plucking out the feathers! ²⁰

“Secondhand smoke is classified as a class-A carcinogen, the same classification given to asbestos.” ²⁹

Passive exposure to cigarette/cigar/pipe smoke is responsible for many clinical problems, including conjunctivitis, sinusitis, air sacculitis, rhinitis and dermatitis.

It is very difficult, if not impossible in some cases, to diagnose and treat respiratory diseases resulting from exposure to cigarette smoke; however, in many cases, all respiratory signs appear to cease if the bird is removed from the contaminated environment.

It may take from a few weeks to several months for this to happen, and medications may be necessary to detoxify the bird’s system. 27, 31

4.2 Second-hand Inhalation From Vaping

Even “vaping” (smoking of e-cigarettes) is a cause of illnesses in humans and birds.

“Formaldehyde, a known human carcinogen found in cigarette smoke, is also found in the vaporized liquid of electronic or e-cigarettes.

The exposure to formaldehyde from e-cigarettes, based on similar chronic use of tobacco, could be five to 15 times higher than from smoking cigarettes.

They found that vaping 3 milligrams of e-cigarette liquid at a high voltage can generate 14 milligrams of loosely affiliated or “hidden” formaldehyde.

According to the American Cancer Society, exposure to formaldehyde has been shown to cause cancer in laboratory animals and has also been linked to some cancers in humans.” ¹¹

Though they’re often billed as a safe, smoke-free alternative to the real thing, doctors and veterinarians aren’t so sure that e-cigs solve any of their predecessors’ problems.

The FDA suggests that vaporized tobacco may expose pets to especially high levels of nicotine and other toxic chemicals like formaldehyde. Pets’ sensitive respiratory tracts are vulnerable to absorbing11 these chemicals.

Birds can also re-expose themselves to these “third-hand vape” chemicals throughout the day as they groom, preen, and interact with owners.¹⁹

Among the components of a typical vaporizer is a small cartridge filled with a highly-concentrated solution of liquid nicotine and other chemicals. Pets can become seriously ill if they ingest even a small amount.

Nicotine toxicity from e-cigarette liquid will result in similar symptoms to poisoning from other tobacco products, but they may progress more quickly and prove more severe.

Contact your veterinarian immediately if your pet has ingested liquid nicotine.¹⁹

“Whether vaping is part of a smoking cessation plan or a permanent replacement for leaf tobacco, pet owners are advised to keep electronic cigarette components safely away from pets.” ¹⁹

4.3 Second-hand Smoke’s Effects On The Respiratory System And Air Sacs

For birds, it is suspected that long-term exposure to second-hand smoke in poorly ventilated areas predisposes them to pneumonia and other respiratory ailments, including lung cancer.

Unfortunately, many of the harmful products in smoke are in the form of gas; therefore, environmental tobacco smoke cannot be entirely filtered out through ventilation systems or special fans.

It can take many hours for the smoke of a single cigarette to clear. And the ventilation systems, including furnace and air conditioning ducts and units, are covered with these toxins, so the forced air will continue to put the toxins in the air.

These need to be cleaned often, especially when the indoor smoking terminates. ^{11, 27}

4.3.1 Sinusitis

4.4 Endoscopic Views Of The Air Sacs Of A Bird Exposed To Second And Third-hand Smoke

“Other abnormalities of the air sacs include increased vascularity, thickened walls and granulomas. These changes may be due to infectious processes or to inhalation of respiratory irritants such as tobacco smoke.

In some cases, a definitive diagnosis can be made from visualization, cytology and/or biopsy of air-sac lesions. Removal or debulking of such lesions has been described using laser and radiosurgery via the endoscope.” 12

5. Toxicity From Exposure To Third-hand Smoke

When smokers puff on cigarettes, cigars, pipes, and other combustible tobacco products, they consume smoke “first-hand.”

As they continue, they also expose themselves and anyone around them to second-hand smoke from their exhalations and the burnt end of their tobacco product.

Regularly inhaling second-hand smoke is especially harmful to infants and children, elevating the risk of ear infections, asthma, and sudden-infant-death syndrome. ¹⁹

5.1 What Is third-hand Smoke?

Both children and pets are especially vulnerable to another type of environmental tobacco: third hand smoke. If you’ve ever walked into a room that reeks of stale cigarettes despite a lack of visible clouds or tobacco products, you’ve experienced third-hand smoke.

Pets and children in smoking households often come into closer and more regular contact with third-hand smoke than adults because of their relative proximity to the floor.

In addition to settling on carpets and spreading through household dust, third hand tobacco particles cling to furniture, walls, curtains, and even the clothes, hair, and skin of smokers.

Nicotine from this lingering tobacco smoke and residue can mix with other chemicals in the air to produce additional cancer-causing compounds that will stick around as well. ¹⁹

Third-hand tobacco is remarkably resilient. A 2011 study published in Tobacco Control found that this residue could remain present in airborne dust and across household surfaces even after intensive cleaning and numerous smoke-free months. ¹⁹

Smokers who light up with pets nearby are forcing them to inhale the dangerous chemicals included in tobacco products. Studies into tobacco’s effect on pets suggest that they suffer many of the same health consequences from repeated exposure as humans do. ¹⁹

5.2 The Danger Of Exposing Birds To Third-hand Smoke.

Pet birds absorb nicotine and other chemicals through their skin and feathers.

This can elevate their risk of developing lung cancer and a range of other conditions if they are exposed to second-and third-hand smoke on a regular basis.

For example, birds who live with smokers are prone to developing allergies, pneumonia, and chronic sinus trouble. ¹⁹

As birds preen their feathers, they may continually ingest chemical particles that have settled on them. The problem is compounded when birds elect to preen their owners’ hair and clothes as well.

Even perching on a surface can prove dangerous, since birds absorb substances (including toxic ones) through their feet.

Standing on the owner’s hands, arms, clothes, furniture, or any surface containing particles of nicotine and tobacco will affect the bird’s feet. Many birds develop pododermatitis (bumblefoot) from these surfaces. ¹⁶

6. Internal Organ Diseases

Birds experience the same high-risk factors as humans. Smoke inhalation exacerbates hemochromatosis (Iron Storage Disease), and nicotine sulfate leads to severe skeletal malformation, reduced body weight, torticollis (aka Wry Neck: twisting of neck to one side), edema, muscular dystrophy, and malformation of the beak, heart, and kidneys. ⁶

6.1 Upper Respiratory Disease

6.1.1 Cataracts, Rhinitis, Sinusitis, And Conjunctivitis

Environmental factors which may precipitate the onset of rhinitis and sinusitis include cigarette smoke, which may damage the mucosa of the upper respiratory tract, allowing pathogens to colonize.

Antibiotics should be used with caution. The eyes, including the nictitating membrane, frequently suffer from exposure to cigarette smoke. The signs include Inflammation, excessive, tearing, redness and infection.

Passive inhalation of cigarette, cigar and pipe smoke can cause chronic ocular, dermatologic and respiratory disease in companion birds.

Birds that live in homes with smokers will often present with clinical signs including coughing, sneezing, sinusitis and conjunctivitis due to continuous irritation of the respiratory system.

The clinical signs may resolve without treatment if no secondary infectious agents are involved, the clients stop smoking, or the bird is placed in a location where there is no smoke. ²⁷

Canaries and finches are particularly susceptible to inhalant toxins because they exchange more air per gram of body weight than do larger birds.

Dangers include carbon monoxide exposure (cages in car garages, leaks from gas heaters), overheated polytetrafluoroethylene (non-stick cookware), carpet freshener, hair spray, glues, paints and smoke.

Birds must be protected from all types of smoke, not just tobacco smoke. Owners must be cautious about exposing birds to smoke from burned food, burned Teflon, and house fires. ²³

To read the photo essay of the author’s rescued cockatiel, who was exposed to years of second-hand smoke, see Appendix B, p. 38.

6.1.2 Oral fungal Infection And Damage To The Beak

“An eight-year-old Umbrella Cockatoo was presented with a nine-month history of progressive sneezing and nasal discharge. The feathers around the beak were moist from a serous nasal discharge.

The rhinotheca (the horn-like covering of the maxilla, or upper beak) had a deep groove that extended from the nostril to the rostral commissure of the upper beak (arrows).

The extent of this defect suggests that the germinative layer of the rhinotheca had been involved in a disease process for over six months. This bird belonged to a heavy smoker.

A mixed population of gram-positive and gram-negative bacteria were cultured from a sinus aspirate. The bird responded to nasal flushing, systemic antibiotics, frequent exposure to fresh air and sunlight, and being removed from a smoke-filled house.” ¹⁴

In another case, a three-month-old Blue and Gold Macaw was presented with a two-week history of serous nasal discharge. There was an accumulation of debris on the feathers of the face.

The nictitating membrane, which moves over the cornea during blinking and in the menace response, was normal. This bird’s rhinitis was caused by exposure to cigarette smoke. ¹⁵

6.2 Lower Respiratory Disease

6.2.1 The Air Sacs And Lungs

The lungs were congested, and also filled with black spots. This is known as anthracosis, and it is the result of accumulation of hydrocarbon particles from cigarette smoke in the respiratory system. (image courtesy Alan K. Jones, Toxic Fumes – The Parrot Society UK).

“A Blue and Gold Macaw was presented with severe dyspnea including a tail bob. He was sneezing and had both ocular and nasal discharges. The only abnormal clinicopathologic finding was WBC=18,000.

Radiographic changes included gaseous distension of the intestines (I) and thickening of the contiguous membrane of the caudal thoracic and abdominal air sac (open arrow).

The client was a heavy smoker, and the lesions resolved over a three-month period when the client quit smoking and the bird received daily exposure to fresh air and sunlight.” (M. McMillan 15

6.2.2 Pulmonary Parenchymatous Abscesses

6.2.3 Subcutaneous Emphysema

6.3 Heart Disease

Smoke intoxication leads to monocytopenia (the deficiency of monocytes, a type of white blood cells) in the blood.

In man, atherosclerosis of the coronary arteries is a major source of morbidityand mortality, and elevated serum lipids (cholesterol, triglycerides, and low-density lipoproteins), hypertension, and exposure to cigarette smoke are important risk factors. The same conditions exist in animals and birds. ¹³

6.3.1 Atherosclerosis

Atherosclerosis is most commonly found in older birds and leads to sudden clinical decline and death.

Risk factors include age, gender, species, increased plasma concentrations of lipids and lipoproteins, high energy diets, physical inactivity, genetics, and coinfection with Chlamydia

Psittaci. Females have a higher incidence of the disease due to the hormone estrogen build up during reproduction. The silent killer: Atherosclerosis in pet birds (Proceedings) (dvm360.com)

6.3.2 Congestive Heart Failure

Another heart condition which is more common in older birds is congestive heart failure. This occurs when the heart no longer acts as an effective pump, and the blood supply to the kidneys is often compromised.

In some cases, there is fluid in the sac around the heart itself, preventing it from pumping optimally. In other cases, the heart may become too muscular or too flabby, with both conditions causing ineffectual pumping.

If the right side ventricle fails (or both ventricles are failing), then usually there is an enlarged liver, fluid found in the body tissues (called edema), and also excessive fluid in the body cavity.

If the left ventricle fails, there is usually excess fluid in the lung tissue. Older birds, overweight birds and perhaps inbred birds are more likely to develop heart disease.

6.4 Damage To The Gastrointestinal Tract

Birds are curious creatures. They will find cigars, cigarettes, or even cigarette butts still containing tobacco on the floor, table, in the ash tray, or on any surface. These all can contain tobacco and poison the bird when ingested.

Common exposure for pocket pets and birds occurs when curious beaks or paws find cigars or cigarettes left within their reach or dropped on the floor. Even the butts of cigarettes can still contain tobacco and result in poisoning when ingested.

There is the risk associated with ingesting tobacco for birds. It can cause significant respiratory irritation (or potentially even cancer) as well.

Ingestion of just a tiny amount of tobacco for birds and pocket pets can result in significant poisoning. Tobacco poisoning can result in the following symptoms: hyperexcitability,

agitation, gastrointestinal (GI) upset (e.g., vomiting, diarrhea, or regurgitation), a racing or rapid heart rate, potential seizures and tremors, and even death.

Treatment includes decontamination (which may include the administration of activated charcoal to bind the tobacco from the intestinal tract), hospitalization for fluid therapy (which will help hydrate the patient), and careful monitoring. ⁹

7. Damage To The Skin And Feathers From Second- And Third-hand Smoke

When toxic particulates and gases in the air assault a bird’s respiratory system, skin, and feathers, feather destruction, plucking and self-mutilation result.

Heat causes the smoke to rise; then, when it cools, gravity brings it back down. The toxins land on the birds, their perches, their cage bars, toys and food. It is also on the smoker’s hands, arms, clothes, and any other exposed skin—even the hair.

If the smoker’s hands are coated with chemicals from holding the cigarette, it is easily transferred to his bird. In one case, an amazon, who turned out to be very sensitive to chemical exposure, began mutilating his feet.

The clinician determined the cause to be his perches which were covered with residue from cigarette smoke. ²⁹

7.1 Feather Discoloration

Of all the tobacco products, nicotine in cigarette smoke poses the greatest danger to birds’ skin and feathers, and second-hand smoke does the most damage, causing both dermatitis and feather damage at presentation.

In addition, the feathers will absorb the odor of the smoke and be discolored by it. Feather-destructive behavior has also been linked to exposure to smoke. ⁵

Some birds who have lived with smokers and are rehomed will continue to carry that odor even after having been bathed. During a bath, the water that rinses off them is often a brownish-yellow color.

Some will even carry the odor until all their feathers have molted out. One group member who rehomed an African grey from a smoker’s house reported that even after a full year, the odor remained on her bird, especially when he was wet.

Other parrots will simply remove the tainted feathers on their own, a practice that may become habit and lead to continued feather-pulling and self-mutilation. ²⁹

Exposure to aerosolized toxins such as cigarette/cigar/pipe smoke will cause these toxins to accumulate on the feathers and skin and cause irritation leading to lesions. S. aureus spp. is

frequently isolated from the lesions, but the birds will usually not respond to antibiotic therapy alone. The lesions may only resolve when the clients stop smoking.

If they continue to smoke, they must do so outdoors and wash their hands and arms and change clothes before handling the birds.

Some cases will only resolve if the bird is removed from the smoke-filled environment, its diet is changed, it is frequently exposed to sunlight, ventilation is improved, a chelator is prescribed, and a topical antimicrobial cream containing steroids is applied.

Topical steroids should be applied with caution to prevent toxicity. ⁴

7.2 Skin Infections

The clinician will look for predisposing factors when attempting to identify a common pathogenesis for the abnormalities he finds on physical examination.

He will be able to identify the true cause of the bird’s ailments when he finds that there is a connection between multiple clinical signs.

When the bird presents with feather abnormalities, respiratory disease, smoke odor on the feathers, systemic fungal infection, poor nutrition, and inadequate exposure to sunlight and fresh air, he will determine that the etiology of the disease is constant exposure to tobacco smoke. ⁵

7.2.1 Staphylococcus Infections

The organism is found in abundant quantities in air and dust. Isolation of the organism can frequently be accomplished from the skin and the mucosa of the respiratory or digestive tract of clinically normal birds.

S. aureus, like other Staphylococcus species, is relatively stable in the environment and can remain infectious for long periods of time outside the host. Given proper conditions, the organism can propagate in an external environment.

Like many bacteria, S. aureus can also develop resistance to disinfectants following continuous exposure, and frequent hanging of disinfectants is required to prevent the development of resistant strains. ⁶

“A five-year-old Amazon parrot was presented with an acute onset of picking at the feet and legs which caused hyperemia and scab formation.

This syndrome, called Amazon foot necrosis, has been reported in Amazona spp., and S. aureus spp. is frequently isolated from the lesions.

However, S. aureus was probably not the primary cause of this problem. This affected Amazon parrot belonged to a client who smoked, and when the owner started washing her hands after

smoking, the foot and leg lesions resolved. The client eventually stopped smoking, and the bird had no further episodes of Amazon foot necrosis.” 8

Case Study

Another bird taken in by the author (Jan. 2022) had a severe Staph infection in his right foot and leg from contact with the owner’s smoke and skin and from his cage and home surfaces.

His foot contained a nidus of infected material on the plantar surface. A nidus is a “nest” of bacteria that settles in one place. If it is disturbed, it will spread along the other skin surfaces. This one had spread to the dorsal foot surface, up the leg, and to several toes.

The leg was inflamed from the foot all the way up to and past the knee joint. One toe was filled with yellow plaque, a sign of Staph infection, and the rest of the toes were red and hot. The bird was in so much pain he held that foot up for months as he was healing.

He could not walk on it without pain. He walked on both his heels of his feet instead. It would be months before the infection resolved sufficiently that he could walk on both feet normally.

The top of the foot had a large, raised section of infection which was spreading across the foot.

This bird was treated aggressively by his avian vet.

He was put on multiple antibiotics until the best one for his condition was found, Robenacoxib at first then celecoxib orally for pain and inflammation, underwent daily soaking, and received topical cream antibiotics.

By the third month, the author began to see an improvement. The redness in the leg and other wound areas resolved. After six months, all but the nidus had healed; it would be another 3 months before

the nidus became flat to the foot. This took a toll on the bird that continues to this day. The bird slept most of the time and had very little energy for quite a while. As time went on, these improved slightly.

The following images describe the infection and healing process (text and images courtesy J. Miesle, Aug. 2022).

7.3 Picking And Self-mutilation Caused By Tobacco Smoke

Many birds self-mutilate. There are numerous possible therapies for the resolution of feather-picking, but before any can be recommended, the underlying medical causes need to be identified and corrected.

When smoking is found to be the underlying cause of the picking, other therapies are required to resolve issues stemming from it.

Treatment of bacterial or fungal folliculitis will need to be initiated, as well as wound management for any other skin or feather diseases and conditions.

Many birds with severe feather-picking issues will resume normal preening behavior when removed from exposure to cigarette smoke.

7.4 Damage To The Feet, Legs, And Face

“The feet and legs should be uniform in texture and color. The feet should have prominent scale patterns on both the dorsal and plantar surfaces.

Changes that result in smoothing of the plantar foot surface can instigate chronic and severe foot and leg diseases.

One of the common etiologies of foot abnormalities is contact with nicotine sulfate from the hands of cigarette smokers. The feet are particularly vulnerable to fungal diseases due to smoking toxicity” ⁶

7.4.1 Pododermatitis

Pododermatitis has been observed in some birds handled by people who smoke routinely. Repeated exposure to the nicotine residues on the hands, arms and clothing of smokers is thought to cause this local irritation.

Macaws and other birds with featherless faces may suffer a similar dermatitis on the bare cheek patches following repeated contact with a smoker’s hands and airborne toxins. ⁶

“An adult Amazon parrot was presented with a ten-day history of progressive picking at the feet with scab formation. The bird was fed a formulated diet supplemented with some fresh vegetables.

The feet were hyperemic (possessing increased blood flow to the tissues), and the feathers were dull and appeared tattered, particularly at the ends. The bird had mild epiphora (excessive secretion of tears) and a serous (watery) nasal discharge.

Both adult clients were heavy smokers. The bird’s ocular, respiratory and foot problems resolved when the clients stopped smoking in the house and washed their hands before handling the bird. ⁶

Smoking-related Diseases

8.1 Aspergillus

Aspergillus is generally found in the respiratory tract, but it can invade any organ and even the skin of the bird. The fungal spores are everywhere, and infections should always be considered to occur secondarily to an immunosuppressive event.

It has been suggested that healthy birds exposed to high concentrations of spores are generally resistant to infections, while immunocompromised hosts exposed to small concentrations of spores are frequently infected.

Factors that influence the susceptibility of a bird to aspergillosis include shipping, overcrowding, malnutrition, poor ventilation, very young or old age, antibiotic therapy (particularly Tetracyclines), corticosteroid administration, respiratory irritants (e.g., disinfectant fumes, cigarette smoke, and ammonia) or concurrent disease (other diseases occurring at the same time). ^{1, 8}

8.2 Pneumoconiosis

“Pneumoconiosis refers to a pathological reaction in the lungs and air sacs due to air pollution. While it commonly involves humans, it has been described in a number of avian species.

It generally involves inhalation, usually of dust and other particulate foreign materials. Chronic exposure to cigarette smoke could result in the accumulation of particulates within the respiratory tract of affected birds” (Bob Dahlhausen, personal communication; used with permission).

8.3 Pneumonia

With pneumonia, the lungs turn a dark pink, and the lung tissue takes on a yellow discoloration. Birds who live in cities, industrial areas, or the homes of smokers generally develop anthracosis, or black spots on the lungs.

The trauma from exposure to these pollutants often causes bleeding within the lungs which can be diagnosed by endoscopic examination. ⁶

8.4 Bacterial Infections

Secondary bacterial invasion of the damaged respiratory epithelium is common and requires therapy; however, therapy for these infections will be of little value if the bird is continuously exposed to smoke. In order to keep pet birds healthy, they should be maintained in well-ventilated, smoke-free environments. ⁶

8.5 Cancer

Smoke-filled environments lead to cancer. Squamous cell carcinomas (skin cancer) are malignant neoplasias that are being reported by clinicians more and more frequently in captive avian species.

These SCCs have been diagnosed in areas such as the beak, eyes, oropharyngeal region, pygostyle (tail base), uropygial gland, and axillary skin.

Although the number of tumors in the captive avian population is unknown, there is increasing evidence that tobacco products from cigar/cigarette smoking contribute to the development of malignant tumors.

The general lifestyle and environment play a vital role in the risk of developing cancer in pets as well as people. ^{11, 18, 30}

“This bird’s beak grew progressively worse until it produced huge amounts of necrotic tissue and the area hemorrhaging excessively.

It was therefore euthanized. Second picture is same bird with material pulled out of the inside of his upper beak.

He spent two years with his beak growing abnormally, getting progressively thicker and more flaky, and finally the inner surface of the upper beak eroded away.

We would periodically put him under anesthesia and clean the impacted food out, but the pulp of the beak was exposed and it would bleed heavily.

At first, I thought it was just an infection and treated it with multiple rounds of antibiotics.

It wasn’t until the pink mass started to appear at the side of the beak that I determined it was neoplasia, and I had to euthanize him within about a week because it grew so fast.” (Julie Burge, personal communication; used with permission).

8.6 Inhalation Toxicosis From Household Sources

Birds are sensitive to inhaled toxins and have historically been used as sentinel animals to detect toxic levels of poisonous gases.

Clients should be educated with respect to the adverse effects that fumes from common household compounds can have on their companion birds.

The clinical changes following inhalation of household fumes may include irritation of mucous membranes, conjunctivitis, rhinitis, dyspnea, or peracute death (peracute: very severe and of very short duration, quickly fatal).⁶

Canaries and finches are particularly susceptible to inhalant toxins because they exchange more air per gram of body weight than do larger birds.

Dangers include carbon monoxide exposure (cages in car garages, leaks from gas heaters), overheated polytetrafluoroethylene (PTFE-non-stick cookware), carpet freshener, hair spray, glues, paints and smoke.

All birds must be protected from all types of smoke, not just tobacco smoke. Owners must be cautious about exposing birds to smoke from burned food, burned Teflon, and house fires. ²³

To print a handout to give to bird owners who smoke, see Appendix C, p. 43

Recommendations:

• Tobacco products can cause significant respiratory irritation or cancer. Ingestion of just a tiny amount of tobacco for birds and pocket pets can result in significant poisoning.
  
  Take the bird to an avian veterinarian immediately if you suspect nicotine toxicity. He will administer chelators such as DMSA (dimercaptosuccinic acid) to decontaminate the bird’s system.
  
  These medications include activated charcoal to bind the tobacco from the intestinal tract. Treatment may also include hospitalization for fluid therapy, which will help hydrate the patient, and careful monitoring.
  
  
• A well-balanced and positive emotional environment helps set the tone for health. Toxic conditions, such as smoke, chemical products, strong aerosolized sprays and odors, should be avoided.
  
  Exposure to cooking in coated cookware or plastics should be minimized. Provide fresh, clean air in a well-ventilated room and natural unfiltered sunlight. Encourage the bird to fly and/or otherwise exercise.
  
  
• Houses are also contaminated by smoking, and this contamination of air, furniture, draperies, etc. lingers for a long time. Those who smoke need to do so outside the house, and visitors should do likewise. Smokers should change their clothing and wash their hands and arms before handling birds.
  
  
• Provide good ventilation. Toxic by-products of tobacco and smoking may take several hours to be eliminated from the air. Hepa® filters on the furnace work best to remove particulates from the air. Providing fresh air is always advisable.
  
  
• Keep all nicotine-containing items, including ashtrays, chewed nicotine gum, and used nicotine patches, out of the reach of pets to prevent accidental consumption.
  
  Birds and other pets may find carelessly discarded cigarettes, cigars, pipes, chewing tobacco, and other tobacco products; these will cause significant poisoning.
  
  
• Watch pets carefully when they are outside since used products and ash still contain residual nicotine. Do not let them pick up cigarette butts, ashes, discarded chewing tobacco, or other tobacco products.
  
  These can attract dogs, as these products are flavored with sugars to hide the naturally bitter taste of tobacco.
  
  Birds in particular should be watched carefully since they may walk on or eat grass that has been treated with garden sprays that may contain nicotine. It is also an ingredient in some natural insecticides.
  
  
• Covered outdoor aviaries for your birds will give them plenty of fresh air and natural light. Covering their cages and play stands while they are outside will help to keep harmful residue from settling on surfaces where they spend their time and prevent wild birds and other animals from defecating on the cages.
  
  Cleaning these aviaries and perches often will help cut down on the possibility of contamination. Frequent bathing is a must for your parrot if you are a smoker. ⁹
  

Conclusion

Today, people know far more about the dangers presented by the use of tobacco products than ever before. If they choose to continue smoking in spite of that, it is at their own risk.

However, they must be aware of the dangers of this habit to their pets. Birds in particular are unable to tolerate second-hand smoke and will become seriously ill when exposed to it.

They require consistent fresh, untainted air to function properly, and it is the owner’s responsibility to provide that for them. Smokers with birds and other pets should seriously consider stopping their tobacco habit for the sake of their pets.

References

1. Bauch L. Mycoses. In: Avian Medicine, Principles and Applications, Ed: Harrison and Lightfoot,. Spix Press, 2006.
   
   
2. Bird Supplies.  Your Parrot’s Respiratory System..
   
   
3. Burroughs D. What is second-hand smoke? Birdtricks.com http://www.birdtricks.com/blog/smoking-around-your-birds/
   
   
4. Cooper J, Harrison G. Dermatology. In: Avian Medicine, Principles and Applications. Ed: Harrison and Lightfoot. Spix Press, 2006.
   
   
5. Doneley B, Harrison G, Lightfoot T. Maximizing Information for the Physical Examination. In: Clinical Avian Medicine. Ed: Harrison and Lightfoot, Spix Press, 2006.
   
   
6. Dumonceaux G, Harrison G. Toxins. In: Avian Medicine, Principles and Applications. Ed: Harrison and Lightfoot. Spix Press, 2006.
   
   
7. Ethos. Veterinary Health, Really Cool Anatomy and Physiology: Avian Respiratory Systems. January 17, 2020
   
   
8. Gerlach H. Bacteria. In: Avian Medicine, Principles and Applications. Ed: Harrison and Lightfoot. Spix Press, 2006.
   
   
9. Guindon S. What’s poisonous to birds and pocket pets? Pet Poison helpline 2011.
   
   
10. Jones M.P. A Case of Squamous Cell Carcinoma of the Beak. In: NAVC Proceedings 2007, North American Veterinary Conference. (Ed). Publisher: NAVC (www.tnavc.org). InternetPublisher: International Veterinary Information Service, Ithaca NY (www.ivis.org) 13-Jan-2007.
    
    
11. Latimer K. Oncology. In: Avian Medicine, Principles and Applications. Ed: Harrison and Lightfoot. Spix Press, 2006.
    
    
12. Lierz M. Diagnostic Value of Endoscopy and Biopsy. In: Clinical Avian Medicine. Ed: Harrison and Lightfoot. Spix Press, 2006.
    
    
13. Lumeij JT, Ritchie B.. Cardiology. In: Avian Medicine, Principles and Applications. Ed: Harrison and Lightfoot. Spix Press, 2006. P. 719
    
    
14. Lumeij JT. Gastroenterology. In: Avian Medicine, Principles and Applications. Ed: Harrison and Lightfoot. Spix Press, 2006″
    
    
15. McMillan. Imaging Techniques. In: Avian Medicine, Principles and Applications. Ed: Harrison and Lightfoot. Spix Press, 2006.P. 317
    
    
16. Miesle. Pododermatitis (Bumblefoot): Diagnosis, Treatment, and Resolution. In: Reviews in Veterinary Medicine,. Ed. Revah I, Publ: International Veterinary Information Service (IVIS).March 8, 2021.
    https://www.ivis.org/library/reviews-veterinary-medicine
    
    
17. Naish D. Publishing with a Hidden Agenda: Why birds simply cannot be dinosaurs. From: Science Blogs: Tetrapod Zoology, 2009.
    
    
18. Ness R. Integrative Therapies. In: Clinical Avian Medicine. Ed: Harrison and Lightfoot. Spix Press, 2006.
    
    
19. Pet Place. Second-Hand Smoke and Pets.
    
    
20. Pine Mountain Vet. Second-hand Smoke and Birds.
    
    
21. Richardson J. Implications of Toxic Substances. In: Clinical Avian Medicine. Ed: Harrison and Lightfoot. Spix Press, 2006.
    
    
22. Samour J. Diagnostic Value of Hematology. In: Clinical Avian Medicine. Ed: Harrison and Lightfoot. Spix Press, 2006.
    
    
23. Sandmeier P, Coutteel P. Management of Canaries, Finches, and Mynahs. In: Clinical Avian Medicine. Ed: Harrison and Lightfoot. Spix Press, 2006. P.908
    
    
24. Seger M. Before you vape: High levels of formaldehyde hidden in E-cigs. In: Health. Jan 21, 2015
    
    
25. Smith, Travis: Does Marijuana have Nicotine?
    
    
26. The Infinite Spider. Blog, Pneumatic Bones: Birds and you.
    
    
27. Tully T, Harrison G. Pulmonology. In: Avian Medicine, Principles and Applications. Ed: Harrison and Lightfoot. Spix Press, 2006. P. 576
    
    
28. What is Marijuana? Drug facts: National Institute on Drug Abuse: National Institute on Drug Abuse; National Institutes of Health; U.S. Department of Health and Human Services.
    
    
29. What is second hand smoke? Bird Tricks. http://www.birdtricks.com/blog/smoking-around-your-birds/ 2009

30. Williams D. Ophthalmology. In: Avian Medicine, Principles and Applications. Ed: Harrison and Lightfoot. Spix Press, 2006.

31. Wissman M. The Top Ten Bird Killers.  Exotic Pet Vet, www.Exoticpetvet.net  2006.

Appendices

Appendix A: Selected Excerpts from Papers Discussing Marijuana’s Effect on Birds

Excerpt 1: Marijuana Toxicity by Travis Smith (text used with permission).

What Is Marijuana?

Marijuana is a drug that affects the entire nervous system of the bird. Birds and other animals are affected by the toxins produced by smoking or consuming marijuana products and byproducts, just as humans do.

In fact, it affects birds more seriously since they have more sensitive respiratory systems, and it would require far less for them to suffer from toxicity. In birds, exposure to marijuana causes severe depression and regurgitation and should be strictly avoided.

Marijuana contains a number of hazardous chemicals. When combustion occurs in smoking materials, the combustion process does not completely reduce the burned material to ash.

The partial combustion of these materials results in large quantities of hundreds of different chemical compounds, such as carbon monoxide, soot, and other particulate matter being given off.

Smokers tend to “hold in” the smoke longer, particularly when smoking marijuana. This allows greater THC uptake (delta-9-tetrahydrocannabinol), which is the reason it is smoked; in addition, sustained “holding in” allows for greater uptake of all the other byproducts in the smoke.

The other particulate matter in the byproducts, such as tiny particles of soot, have more time to get absorbed by the lungs and not be exhaled. There are a number of organic compounds that are known carcinogens in marijuana smoke.

Even though there is no nicotine, some of the other cancer-causing chemicals in tobacco are present in cannabis smoke – and at twice the levels they are in smoke from tobacco. Any type of smoking will damage the lungs; it maybe a quick way to maximize uptake of THC, but it comes at a price. ²⁸

Excerpt 2. High Crimes & Parrot Health: Implications Of Loosening Marijuana Restrictions

An increasing number of cities and states have moved ahead with legislation to legalize or decriminalize marijuana for medical or recreational use. Medical marijuana is now legal in 23 states and Washington, D.C. In November, Alaska, Oregon and Washington, D.C. joined Colorado and Washington State when ballot measures passed to allow the sale and use of recreational marijuana.

The increase in availability of legal marijuana has legal, health, and medical implications for pet birds and their owners.

Although there is not yet extensive research available on the specific effects of marijuana smoke on pet birds, veterinarian Cassee Terry of Redmond, Oregon cautions that the effects could be severe.

“Birds are much more sensitive to smoke inhalation toxicity than other animals,” she explained. “Generally,” Terry observed, “Lung toxicities are more severe in birds.”

There are several reasons for this. Birds have very efficient respiratory systems, which means that with each breath, birds extract many more air particulates than humans.

In addition, birds breathe at an increased rate compared to humans, so airborne toxins such as smoke will have an increased impact on birds. Bird anatomy also plays a role.

In addition to their lungs, “Birds have a system of air sacs,” explained Megan Jones, a researcher in bird behavior at Florida State University, “so when they inhale, the air goes first into the posterior air sacs, then into the lungs when they exhale.”

But that breath remains in the bird, Jones explained, for yet another breath. The air travels “then through the lungs to the anterior air sacs on the second inhale, and is exhaled out of the body on the second exhale.”

Exposure to second-hand smoke of any kind, even from kitchens, can have negative health consequences for pet birds. Repeated exposure can cause skin and eye irritation and infection, respiratory infections, and chronic respiratory disease.

Birds can develop symptoms such as coughing, sneezing, and sinus and eye infections, and these may lead to secondary bacterial infections which may even be fatal.

How Marijuana Can Affect Pet Birds

Peer-reviewed studies have not yet been published on the effects of so-called “edibles,” or edible products infused with THC oil, on birds.

Because all species of animals process different chemicals differently, don’t assume that you can accurately determine how much of a cannabis-edible product a bird could safely ingest based merely on its weight as compared to your own.

In addition, effects such as distortions of balance and the senses, which humans might experience as a pleasurable “buzz,” can be uncomfortable, disorienting and even frightening for animals.

Terry cautioned that in general, “The effects last longer when ingested than smoked in birds and other species.” Therefore, even if a small amount of edible marijuana did not prove fatal or cause illness, a bird could experience any unsettling effects for longer if exposed to an edible product.

Some ingestion of marijuana by pets occurs by accident, through exposure to second-hand smoke, or when a pet raids its owner’s unattended stash of marijuana or edible products.

The Legal Ramifications For Exposing Your Pet Bird To Marijuana

Although there are some reports of pet owners attempting to treat their pet’s diseases with marijuana, many anecdotal reports of bird exposure to marijuana appear to result from the owner’s own use when their diminished judgment leads them, or their friends, to feed marijuana or its by-products (such as bong-water) to pets or blow smoke in their faces to see their response.

Before intentionally administering marijuana to your bird, either medicinally or in fun, you should be aware that there could be legal consequences for you. Intentionally subjecting your pet to the effects of marijuana could be viewed as animal abuse or cruelty in some states.

Twenty-nine states have laws either requiring or permitting veterinarians to report animal neglect, cruelty, or abuse to authorities.

Although there are numerous examples on social media of people intentionally getting their birds high, some people who intentionally expose their pets to this drug are prosecuted.

You should make yourself aware of criminal drug laws and animal abuse and cruelty laws in your state.

As you could be held legally responsible for actions that are seen by authorities as animal cruelty or abuse, you should make it clear to your friends that any acts which might be illegal or harmful to your bird’s health are unacceptable.

To reduce the temptation for your friends to do something irresponsible, you should keep your bird in a separate room, away from potentially toxic fumes, in an area not connected by shared ventilation systems.

If your bird does inhale smoke or consume marijuana products and becomes ill, taking prompt action to save her, like bringing her to a vet, could still be seen as a mitigating factor in your favor.

Even in states where medical marijuana is approved for human use, veterinarians are not permitted to prescribe it for animals.

According to an article on the American Veterinary Medical Association website, which explores the medical marijuana debate in veterinary circles, “Physicians in states where medical marijuana is sanctioned are exempt from prosecution by the state for recommending the Schedule I drug to patients.

Such protections do not apply to veterinarians, for whom it is illegal in every state to prescribe or recommend marijuana to treat a patient.”

Some people are nonetheless using marijuana, usually in edible form, to treat chronic pain and illness in their pets.

However, due to the lack of available medical research, dosage and administration is often a matter of guesswork.

For bird owners, in addition to moral and ethical considerations, there may be criminal consequences for administering marijuana to your bird.

Appendix B: A Photo Essay—Pedro’s Case Study by J. Miesle

Pedro was an older cockatiel of indeterminate age that was surrendered to Sugarcreek Bird Farm in Bellbrook, Ohio on Saturday, Dec. 12, 2015. I picked him up the following day.

At first glance, he didn’t look bad. From a distance, there just seemed to be a few feathers missing on his shoulders, but there was so much more. He had led a very hard life.

He’d been neglected, fed a terrible, cheap seed diet, subjected to years of toxic cigarette smoke by several adults, and confined to a filthy, small cage his entire life. He couldn’t even spread his wings—his muscles had atrophied. His feathers hid a much more serious condition.

His skin was dry, pruritic, infected, and damaged. Open wounds covered some of his skin, particularly on the tops of the wings and the underwing areas.

His feathers were substandard and blunted; it was obvious he had not grown in new feathers in a very long time.

His feet were very dry, flaking, and had lesions on the dorsal and planter surfaces of the feet and up the legs.

His head was missing feathers, and the skin on the crown was bare and infected. His feathers were barbered from being confined in such a small cage. He couldn’t even stretch them without scraping the sides of the cage. His beak showed signs of beginning hyperkeratinization on the tip and at the tomia, or cutting edges of the beak.

His body position was abnormal; he would perch on both feet and lean forward, as if unable to balance otherwise.

His back was rounded and his tail curved down. The tail bobbed as he breathed, a sign of respiratory distress. He kept his head down most of the time, and his crest was low, indicating depression and fatigue.

His body has been ravaged by pruritis–dry, red, sore, inflamed, infected, pus-filled skin. His feathers, thin and dystrophic, would fall out with little provocation. His nares were filled with debris.

His dry feet had sores on them, and he was missing nails on two of his toes, one on each foot. His uropygial gland was beginning to atrophy, although the feather tuft was still there.

I suspected he was suffering from severe Vitamin A deficiency as evidenced in the blunted choanal papillae in the roof of his mouth and the pruritic, inflamed condition of his skin.

The tissue on his wing was extremely thin and completely unfeathered, making the patagia (wing web) transparent. He was underweight, only 79 grams, and his keel protruded. The muscle mass in his breast was soft and thin. A pitiful little creature, indeed.

Dec. 12

First, I cleaned out his nares. They were full of debris, but fortunately there was no concretion yet, and so no rhinoliths had formed. I trimmed his overly long nails and took my time examining him more thoroughly this time.

He was very dirty, and his feathers reeked of cigarette smoke. I bathed him so that I could get a really good look at his entire body, especially his feathers and skin, and also to remove as much of the nicotine residue and odor as possible.

I was surprised to see how much of his skin was pruritic and featherless. I couldn’t see this from a distance because the wings hid the unfeathered areas under them, and the breast feathers hid the bare skin on the axial areas and area around the vent.

Everything I did was painful; he did not want to be touched. There was poor feathering on his entire body, and the feathers that were there were dystrophic and matted, even after the bath.

There were sores at the shoulder and elbow joints, on the patagium, and on the bones of the wings. There were no feathers under his wings or on the sides of his body.

His bare thighs also indicated an allergic reaction to the smoke. The vent seemed unusually small and tight, as though his droppings had been abnormal.

Dec. 13-30

We had a 9:30 appointment with my avian veterinarian, Bob Dahlhausen, that day. He examinined him and took choanal and fecal samples for Gram’s stains and skin impressions of the pruritic areas.

He didn’t think he was very old, possibly in his late teens. Since cockatiels can live as long as 30 years, that’s not very old at all. But longevity is determined also by living conditions.

The Gram’s stains were normal—and I was quite surprised by this. The fecal grams showed normal flora in the intestinal tract, and the oral stains showed only a small amount of debris. No infection.

The skin was pruritic from the heavy smoking environment and his picking. His feet were dry and had small sores on them from poor perches and contact with smoke on perches or hands.

He confirmed that the uropygial gland had begun to atrophy, but we might be able to stop it from continuing since it still had the little feather tuft, and he was able to express a small amount of sebum.

Pedro was suffering from severe Vitamin A deficiency as evidenced by the lack of papillae surrounding the choanal slit and his skin and feather condition.

Pedro was given the chelator, DMSA, to clear the lungs and air sacs of the poison inflicted by years of exposure to smoke.

Dr. Bob also gave him an injection of doxycycline and Robenacoxib to begin the healing of the skin infection; they would reduce the pain and inflammation he was experiencing.

At home, I was to give him Optomega (now Vetomega), Emeraid with additional vitamins, Celecoxib after a week had passed, and apply topical Aloe Vera liquid gel.

At the office, his weight had dropped to 73 grams. I attributed that to the stress of the day–the trip to and from the office, lack of food during that time, the handling, and the newness of everything.

He did not do well on Wednesday. He had very little energy and slept most of the time.

He sat hunched over, and he ate very little all day. I think he was exhausted from his visit—the drive to and from, the exam, the injections, tests—it was all too much for him.

His weight plummeted to 69 grams by evening. I was giving him Emeraid all day, hoping to stimulate his appetite, but it wasn’t doing the job. I considered that the DMSA, nasty concoction that it is, had upset his crop, and that could be why he wasn’t eating.

So I decided to hold off on giving this to him for a while until he had gained some weight and was more stable. He hadn’t had the medication since the morning, and by later in the evening he had begun to eat.

I kept him up later than the rest of the flock so I could get more Emeraid and food into him and spend some quality time with him. This would be our evenings for a long time.

2016

Jan 4-20

He was able to keep down half dosage of DMSA, and his weight had stabilized at around 78 g. His skin condition was improving slightly.

He was no longer pruritic. It would be a long time, though, before we saw any feather growth. To encourage molting and feather regrowth, I was told to begin oral Thyrosyn.

We were finishing up the second week of DMSA and I was to wait two weeks and do another round. I had begun giving him Celebrex (celecoxib) the week before to aid in decreasing the discomfort from the skin irritation.

Today, I had him in to see the Dr. Bob again. He determined that the skin was vastly improved, and he recommended continuing the medications—Emeraid, vitamins, Vetomega, and celecoxib—and to finish out the DMSA.

At this point, any redness on the skin was due to his picking, not infection. The celecoxib had made a huge improvement in his skin irritation, and he rarely picked at his wings anymore.

Jan. 14

March 1-17

I felt he had done well with his appetite, skin improvement, and general health, although he still was sitting slumped a lot. We had finished up the DMSA and I was giving him all the meds.

By this time I had begun giving him Silymarin, or Milk Thistle, since I felt there was probably some degree of liver damage. I based this assumption on the dark, greasy appearance of his feathers and some slight hyperkeratinization of his beak.

I dremmeled it a little in the beginning from time to time, but by this time it had ceased to overgrow.

I took him back to see Dr. Bob. I had noticed that the top, round bones on his elbow joints were becoming quite enlarged. The left was larger than the right, but it too was beginning to grow.

It was fixed and immovable, so I doubted it were a neoplasm. Still, it was abnormal and I wanted him to take a look at it. He manipulated it, noted that it articulated well, and the movement wasn’t painful to him. I was to let it alone and just keep an eye on it. He removed an ingrowing feather.

March 17

Pedro only lived with us for four months before he passed away. We have no idea how many years this poor bird was forced to live with cigarette-smoke toxicity. I don’t know what condition his lungs and air sacs were in.

His body had been enduring so much pain, and his life had been so miserable.

I can only hope the readers understand the dangers of imposing their smoking habits onto their birds and that they are motivated to stop smoking—for their sakes as well as their birds’.

His was by far the worst case of nicotine toxicosis the author had ever seen, and one of the worse Dr. Bob had ever seen.

Appendix C. Handout for Bird Owners Who Smoke.

You may print pages 44-47 and give it to people you know who smoke and have pet birds.

Smoking And The Damage To Your Bird’s Health

Birds and other exotic animals have extremely sensitive respiratory systems. They have small, fragile lungs, and their air sacs do most of the respiratory work.

It takes very little to negatively impact the lungs and air sacs of birds. The respiratory system of birds is adversely affected by any form of air pollution.

Signs Of Tobacco Toxicity Are:

Tobacco Products Contain Varying Amounts Of Nicotine: 

Animals may lick up toxic chemicals. Nicotine, tar and carcinogens may land on their feathers after the smoke in the air settles, thus increasing their chances of developing cancer.

In addition, they may eat products containing nicotine, such as cigarettes, cigars and chewing tobacco, nicotine gums and patches.

Nicotine is often used as an insecticide, so birds must not be allowed access to any such products or be permitted to walk onto grass and other foliage that has been sprayed.

Marijuana

The toxins produced by smoking marijuana are dangerous to birds because of their sensitive respiratory systems; they require far less to suffer from toxicity. In birds, exposure to marijuana causes severe depression and regurgitation and should be strictly avoided.

Marijuana may be smoked, eaten, drunk, or inhaled. Although it does not contain nicotine, it is often rolled up with tobacco or inside cigar leaves, so nicotine will be included in the smoke.

Combustion produces large quantities of hundreds of hazardous chemical compounds, such as carbon monoxide, soot, and other particulates.

Holding in the smoke allows for more time for THC and other bi-products to be absorbed by the lungs and not be exhaled.

Cancer-causing chemicals in tobacco are present in cannabis smoke – and at twice the levels they are in smoke from tobacco.

The Marijuana Smoker And His Pets Will Encounter:

Toxicity From Second-hand Smoke

Exposure to tobacco smoke causes respiratory disease and diseases involving other systems of the body. A lit cigarette, pipe or cigar releases smoke and toxins, from both the lit end and filtered end.

People and animals constantly exposed to tobacco smoke are more likely to develop and die from heart disease, lung cancer, and breathing illnesses.

Tobacco smoke contains over 4,000 thousand different chemicals that fill the air as either gases or particulates, including 69 compounds that are known to cause cancer.

These include formaldehyde, ammonia, cyanide, nicotine, benzene, chromium, nickel, vinyl chloride, arsenic, carbon monoxide, methane, tar, carcinogens (cancer-causing agents).

The concentration of these carcinogenic chemicals is actually higher in secondhand smoke than in the fumes directly inhaled by smokers.

Second-hand smoke is classified as a class-A carcinogen, the same classification given to asbestos.

Passive exposure to tobacco smoke is responsible for many clinical illnesses, including conjunctivitis, sinusitis, air sacculitis, rhinitis and dermatitis.

In many cases, respiratory signs will cease if the bird is removed from the contaminated environment.

It may take from a few weeks to several months for this to happen, and medications, such as chelators, may be necessary to detoxify the bird’s system.

Vaping

Vaporized tobacco may expose pets to especially high levels of nicotine and other toxic chemicals like formaldehyde.

Birds’ sensitive respiratory tracts are vulnerable to absorbing these chemicals. Birds can also re-expose themselves to these “third hand vape” chemicals throughout the day as they groom, preen, and interact with owners.

The cartridge is filled with a highly-concentrated solution of liquid nicotine. Birds can become seriously ill if they ingest even a small amount.

Nicotine toxicity from e-cigarette liquid will result in similar symptoms to poisoning from other tobacco products, but they may progress more quickly and prove more severe.

Formaldehyde, a known carcinogen, is present in the vaporized liquid of e-cigarettes, and it could be 25 times higher than that found in cigarettes.

Contact your veterinarian immediately if your pet has ingested liquid nicotine. Keep electronic cigarette components safely away from birds

Smoking’s Effects On The Bird’s Respiratory System

Second-hand smoke predisposes birds to pneumonia and other respiratory ailments, including lung cancer.

It cannot be entirely filtered out through ventilation systems or fans. It can take many hours for the smoke of a single cigarette to clear.

And the furnace and air conditioning ducts and units are covered with these toxins, so the forced-air furnace will continue to put the toxins in the air.

Furnaces, vents, and ducts need to be cleaned often, especially when the indoor smoking terminates.

Endoscopic Views Of The Air Sacs Of A Bird Who Lives With A Smoker

Upper Respiratory Disease In Birds. Rhinitis and sinusitis from cigarette smoke damage the mucosa of the upper respiratory tract, allowing pathogens to colonize.

The eyes, including the nictitating membrane, frequently suffer inflammation, excessive tearing, redness and infection.

Smoking Toxicity’s Effects on Other Systems and Parts of the Body. Smoke inhalation exacerbates Iron Storage Disease, and nicotine sulfate leads to severe skeletal malformation, reduced body weight, torticollis (twisting of neck to one side), edema, muscular dystrophy, and malformation of the beak, heart, and kidneys.

Effects on the Circulatory System and the Heart. Smoke intoxication leads to poor white blood cell development, hypertension, atherosclerosis, congestive heart failure, and heart attack in animals and birds.

Effects on the Skin and Feathers Nicotine in cigarette smoke poses the greatest danger to birds’ skin and feathers, and second-hand smoke does the most damage, causing both dermatitis and feather damage.

The feathers will absorb the odor of the smoke and be discolored by it. Feather-destructive behavior has also been linked to exposure to smoke.

Smoke toxins accumulate on the feathers and skin and cause irritation leading to lesions. Staphylococcus ssp.is frequently isolated from the lesions, and antibiotic therapy is needed.

Many birdshave bacterial infections or fungal folliculitis from smoke exposure and require wound management.

Smoke lands on the birds, their perches, cage bars, toys, and food. It is also on the smoker’s hands, arms, clothes, skin, and hair.

Smoker’s hands transfer toxic chemicals to the bird. Birds will mutilating their legs and feet because their perches were covered with smoke residue.

Some rehomed birds carry that odor even after having been bathed and will carry it until all their feathers have molted out.

Some resort to feather picking to remove the tainted feathers. Many birds will resume normal preening behavior when removed from exposure to cigarette smoke.

Effects On The Feet, Legs And Face

The feet are particularly vulnerable to fungal diseases as a result of smoking toxicity. The feet and legs should have prominent scale patterns both top and bottom of the foot.

Smoothing of the bottom of the foot’s scale pattern can lead to severe foot and leg diseases.

Nicotine contact is a common cause of foot abnormalities. Foot infections are due to handling by smokers since nicotine residue on the hands causes irritation.

Macaws suffer dermatitis on the bare cheek patches following repeated contact with a smoker’s hands.

Smoking-related Diseases

Aspergillus. Aspergillus is generally found in the bird’s respiratory tract, but it can invade any organ and even the skin. The fungal spores are everywhere, and birds exposed to smoke have immune systems that are weak, so they are unable to fight off the disease.

Pneumonia. With pneumonia, the lungs turn a dark pink, and the lung tissue takes on a yellow discoloration.

Birds exposed to cigarette smoker generally develop black spots on the lungs. The trauma from exposure to these pollutants often causes bleeding within the lungs.

Bacterial infections. Secondary bacterial infections are common and require medical therapy. Staphylococcus,. Staph is found in abundant quantities in air and dust.

S. aureus can remain infectious for long periods of time outside the host. It can also develop resistance to disinfectants following continuous exposure, and frequent changing of disinfectants is required.

Cancer. Exposure to cigarette smoke leads to cancer. Skin cancer is being reported by clinicians more and more frequently in pet birds.

It has been diagnosed in areas such as the beak, eyes, mouth, tail base, preen gland, and skin on the body.

Recommendations: take the bird to an avian veterinarian immediately if you suspect nicotine toxicity. Treatment may include medications, hospitalization for fluid therapy, and careful monitoring.

Houses are also contaminated by smoking, and this contamination of air, furniture, draperies, etc. lingers for a long time.

These must be cleaned often. Smoking must be done outside, and smokers should change their clothing and wash their hands and arms before handling birds.

Provide good ventilation. Toxic by-products of smoking may take several hours to be eliminated from the air. Hepa® filters on the furnace work best to remove particulates from the air.

Provide fresh air. Keep all nicotine-containing items, including ashtrays, chewed nicotine gum, and used nicotine patches out of the reach of pets to prevent accidental consumption.

Birds and other pets may find carelessly discarded cigarettes, cigars, pipes, chewing tobacco, and other tobacco products; these will cause significant poisoning.

Clean cages and perches daily. Frequent bathing is a must for your parrot if you are a smoker. Other pets suffer significantly too. It takes very little tobacco or nicotine to be toxic to a dog or cat.

Images:   Relevant Avian Anatomy Image Gallery 

Commonly Used Avian Medical Terms

Abdomen/Abdominal region:  between the thorax and pelvis: ventral part of bird, between vent and posterior sternum; flight muscles located between belly and breast

Abdominocentesis: drawing out fluid from abdominal cavity

Absess: localized accumulation of puss; associated with infection

Acanthosis: benign overgrowth of prickle-cell layer of skin; increased thickness of stratus spinosum (layer of epidermis containing prickle cells, also called spinosa layer and prickle cell layer), due to hypertrophy of cells

Accipiter: a certain group of hawks, including Sharp-shinned, Cooper’s and Northern Goshawk

ACE inhibitor: Angliotensin-converting enzyme; decreases function of this enzyme. Dilates blood vessels.

Acetabulum: hipbone socket that receives head of femur. The cup-shaped cavity at the base of the hipbone into which the ballshaped head of the femur fits.

Achromatosis: failure to lay down normal feather pigment

Acid: fluid containing high proportion of hydrogen ions, gives fluid sour taste; measured by pH units, 2 the most acid, 14 the least, chemical reactions in body take place at/near neutrality

ACTH: Adrenocorticotropic hormone secreted by pituitary gland which stimulates the adrenal gland to work

Acinar holocrine sebaceous glands: smallest secreting portion of the gland, releases the secretion, sebum. Small glands that release sebum, e.g., uropygial gland

Acinetobacter: a gram neg. pathogen bacteria; a milder pathogen

Acquired disease: caused by disorder, injury, tumor

Activated charcoal: treated to increase adsorptive power (ability to have chemicals adhere to it), used to treat poisoning

Active immunity: produced when immune system reacts to a stimulus (virus or bacteria) and produces antibodies and cells which protect it from the disease

Acuminate: abruptly narrow to sharp point

Acute: sharp, severe, sudden, rapid onset, short-course symptoms

Adenitis: gland inflammation

Adenocarcinoma: malignant tumor or gland-like structure arising from secretory epithelium 

Adenoma: benign epithelial tumor composed of cells from glandular epithelium

Adenovirus: causes hepatitis in birds

Adhesion: band of fibers that hold structures together in abnormal way

Adipose: fatty tissue, cells that store fat

Adjuvant: substance added to killed vaccines to stimulate stronger or faster immune response by body; common ones contain aluminum compounds, drugs or chemo/radiation therapy; supplemental treatment

Adrenal cortex: large, outer, firm layer of adrenal gland

Adrenal glands: 2 small glands near kidneys, produce hormones

Adrenaline: hormone produced by adrenal glands, elevates heart and respiration rates, aka epinephrine

Adsorb/Adsorbent: solid substance which attracts other molecules to its surface

Aerobe/Aerobic bacteria: organism that lives only in presence of oxygen

Anaerobic grows in absence of oxygen

Aeromonas: gram-negative, anaerobic, rod-shaped bacteria, grows in water and soil, aerobic,

Aerophagia: gulping air, spasmodic swallowing of air, nervousness and anxiety, gas in intestinal tract

Aerosol: system in which solid or liquid particles are suspended in air or other gas

Afferent and Efferent nervous system: sends impulses or signals to and from the brain/central nervous system

Aflatoxins: toxic compound composed of molds, contaminates, in stored food, cases aspergillosis

Agenesis: absence of body part

Agglutination: sticking together of insoluble antigens such as bacteria, viruses, or erythrocytes by an antibody. Agg. Assays used to type human blood before transfusion

Agonist: second drug which stops action of the first drug; drug which has physiological effect; has an affinity to a cellular receptor; binds to a cellular receptor for another drug without producing any physiological effects itself

Airfoil: special shape of birds’ wings, produces lifting effect as it moves forward through air  

Airfoil Wing: shaped with curve on top rather than beneath

Air sacs: thin-walled, membranous sacs of respiratory system, allows unidirectional flow of air into lungs and through body; 9 air sacs: 4 paired: 2 cervical, 2 anterior thoracic, 2 posterior thoracic, 2 abdominal and 1 unpaired interclavicular. Fill parts of body cavities and penetrate muscles and bones; interconnect with each other and lungs to form efficient one-way path for air movement during breathing; help remove waste heat generated during flight, not used to exchange oxygen and CO2

Air sac mites: small, dark mites in windpipe and air sacs, irritation leads to asphyxiation, wheezing, whistling in breathing, Ivermectin

Air space: pocket of air between the shell membranes at the large end of the egg; as the developing embryo uses water and additional water evaporates from the shell, air moves into the egg from outside, expanding the air space

Airie: A nest built on the wall or side of a cliff by a raptor

Alar Bar: A contrasting line running on the front edge of the mid-wing section to the bird’s body

Albino: (Leucistic) completely white animal, cannot make pigment, blue or pink eyes.  Please refer to Albino / Leucistic / Partial White / Pied Hummingbirds for photos and more information

Albinism: Occasional and erratic occurrence of white plumage, seen partial or complete in non-white plumage birds, caused by coloring deficiency in the feathers

Albumin: egg white, composed of water and protein; it is a protein in the blood responsible for maintenance of osmotic (water) pressure in the blood; attaches to large molecules in blood and transports them; produced by liver, aka serum albumin.

Alele form of gene; one of two or more alternative forms of a gene, occupying the same position locus on paired chromosomes and controlling the same inherited characteristic

Alimentary: food or digestive tract

Aliquots: sample

Alkaline: substance with few hydrogen ions, pH over 7, e.g., lye

Allantois: membranous sac that balloons off a bird embryo’s gut; solid wastes produced by the developing embryo that can’t be passed through the eggshell are diverted into the allantois

Allergen: causes allergic reaction

Allo: other, deviating from norm

Allo-feeding/preening: mutual behavior 

Allogenic: birds of same species but different genetic constitution (antigenetically distinct)

Allopatric: biologically related to or taking place in different areas, esp. in speciation in which isolated populations evolve into good species

Allopecia: feather loss; can be nutritional or behavioral; often an adrenal disease

Alternate plumage: breeding plumage, Usually the more colourful plumage seen on an individual adult bird during before and after nesting season, also known as alternate plumage.

Altricial: Condition describing certain young birds when hatched, that have no feathers, eyes are closed and totally dependent on their parents.

Alula: small joint on manus, like thumb, 3-4 quill-like feathers attached. Used for low-speed flight and maneuverability. Prevents stalling in flight. The feathers function like slats on planes by increasing the camber of the wing, helping bird to land and take off, supported by anterior-most digit

Alular quills: the three feathers attached to the alula originating from base of primaries; low- speed fight, landing, take-off; attached to the thumb or pollex, located midwing area.

Alular quill coverts: small feathers coving the quilt of each flight feather

Ambient: surrounding, as in air temperature

Amino Acids: any of large group of compounds containing amino and carboxyl group; building blocks of proteins; occur naturally in plants and animal tissue

Aminoglycoside: a class of antibiotics which acts by interfering with bacterial protein synthesis within the bacteria; results in death of the bacteria; Include gentamicin, kanamycin, neomycin, streptomycin, tobramycin, amikacin; many not well-absorbed by digestive system, so administered IM or topically

Amniotic A modern egg’s shell having a waterproof membrane

Amorphous: without form, shape or boundaries, not allowing clear classification or analysis, as in amorphous urates

Amylase: digestive enzyme, produced by pancreas; breaks down carbohydrates and starches; in saliva

Amyloid: containing/resembling a starch; abnormal proteins

Amyloidosis: malformed or abnormal amyloid proteins are deposited in organs or tissues and cause harm; amyloids build up in tissues either as a primary idiopathic disease or secondary chronic disease as in TB or osteomyelitis; results in cell toxicity and organ dysfunction

Amylum: chemical starch as in potato

Anabolic steroid: type of steroid which promotes tissue building, like muscle (not a corticosteroid like cortisone)

Anabolism: process which changes food into living tissue, e.g., bone growth; the constructive phase of metabolism in which body cells synthesize protoplasm for growth and repair

Anaerobic bacteria: live and grow in no or little oxygen, e.g., C. tetani (tetanus)

Anaerobe: organism that grows without oxygen; many harmless

Analgesic: pain-relieving drug

Anamnesis: history of bird and current illness; about caretaking, environment, husbandry, changes

Anamnestic response: faster or greater immune response produced by animal which had previously encountered that specific antigen. Memory cells are responsible for this quick response; aka “secondary response.”

Anaplasia: loss of differentiation of cells; irreversible alteration in adult cell toward more primitive cell types; a characteristic of tumor cells; change in the structure of cells and their orientation to each other.

Anastomosis: surgical union of parts, esp. hollow, tubular parts;

1. communication between 2 organs or vessels by collateral channels
2. surgical, traumatic, or pathological formation of an opening between two normally distinct spaces or structures; surgery: the surgical union of two hollow organs, e.g. blood vessels or parts of the intestine, to ensure continuity of the passageway
3. intestinal establishment of a connector between 2 distinct parts of the intestines
4. natural joint: the connection or place of connection of two or more parts of a natural branching system, e.g. of blood vessels, leaf veins, stems of woody plants, or rivers

Androgen: hormone producing male sex characteristics; e.g., testosterone

Androstenedione: steroid produced by testes, adrenal cortex, and ovaries; immunization against it increases fertility

Anechoic: unable to move, faint, feel, respond, exhausted, in ultrasonography, the absence of internal echoes

Anemia: a decrease in number of circulating erythrocytes, below normal amount of hemoglobin in RBC, or combination of both; causes weakness and debilitation; caused by blood loss, decreased RBC production, increased RBC destruction; caused by blood trauma and GI bleeding, hemorrhage, ulcers, liver disease, GI foreign bodies;

Anesthesia: loss of sensation or feeling induced by drugs

Angiography: x-ray of vessels after injecting contrasting fluid

Angiotensin-converting-enzyme inhibitor (ACE inhibitor): drug which decreases the function of this enzyme; angiotensin is a blood vessel constrictor, so ACE inhibitors dilate blood vessels

Anhedral Downward curve of a bird’s wing in flight. E.g.,. Turkey Vulture.

Anisocoria: pupils of eyes not equal size (refer to Wing Anatomy)

Anisocytosis: abnormal size variation in erythrocytes

Anisodactile: 3 toes in front, one behind, as in perching wild birds

Ankylosis: abnormal immobility and consolidation of joint; caused by destruction of membranes that line the joint or faulty bone structure or arthritis; joint assumes least painful position and remains fixed in it, sometimes permanently

Annular: ring-shaped, circular, as in inflammation and crusting in dermatitis or ringworm

Anorexia: loss of appetite

Antebrachium: the forearm area, supported by the radius and ulna

Anthelmintic: substance that destroys parasitic worms (intestinal helminthes)

Anthracosis: benign deposits of coal dust in lungs

Anthropomorphism: interpreting behavior of animals in terms of human feelings, motivations or characteristics

Antibiogram: antibiotic sensitivity test

Antibiotic: natural or synthetic chemical substance that kills microorganism or inhibits their growth; treats bacterial infections; Broad-spectrum antibiotic treats wide variety of bacteria (e.g., penicillin, tetracycline, erythromycin); Some treat specific groups, like Gram positive and Gram neg. some kill and some prevent bacteria from reproducing (bactericidal and bacteriostatic)

Antibiotic beads: combat musculoskeletal infections; lined with tobramycin powder

Antibody: specialized protein contained in the blood serum and formed by the b-lymphocyte white blood cell; responds to an antigen to which animal has been exposed; antibody destroys or inactivates certain foreign substances in body, especially microbes; produced by immune system as protection against infection and disease

Antisense: having a strand of DNA complementary to other genetic material so that expression of a trait can be regulated.

Antiseptic: acts against sepsis (toxins in blood); formulated for use on living tissue to prevent or inhibit growth/action of organisms

Antiserum: blood serum from animal after immunization with particular antigen; contains antibodies specific for that antigen as well as other antigens with which the animal has previously been immunized.

Antispasmodic: relieves or decreases muscle spasms; includes smooth muscles (muscle in intestines that causes them to contract and move food through digestive system)

Antitoxin: an antibody with the ability to neutralize a specific toxin.

Antitussive: cough suppressant

Anular pad: ring-shaped vessel in eye

Anuria: kidney failure, no urine produced

Aortic arch: curvature of aorta where it turns from its cranial path to a caudal one and becomes the thoracic aorta

Apex: narrow tip of heart at distal end

Aplasia: lack of development of an, tissue, or cell

Aplastic anemia: erythrocytes, leukocytes and platelets not produced in sufficient numbers

Apnea: absence of breathing

Aponeurosis: broad, sheet-like tendon

Apoptosis: programmed cell destruction

Appositional: placed in proximity

Apterium/Apteria: bare, unfeathered areas between feather tracts

Aqueous humor: fluid in eyeball, provides nourishment to interior eye, keeps eyeball inflated

Arboreal A tree dwelling bird

Archaeopteryx First fossilized bird known to exist.

Aerial insectivores: Bird species who feed on insects while flying

Arrhenoblastoma: ovarian stromal tumor

Arrhythmia: variation from normal heart rhythm

Arteries: thick-walled vessels that carry blood away from heart to lungs and body tissues; pulmonary arteries carry deoxygenated blood to lungs, but all other arteries carry oxygenated blood; have muscular walls to allow contraction and expansion to move blood throughout the body

Arthritis: inflammation and swelling of joints

Arthrodesis: aka artificial ankylosis or syndesis; artificial induction of joint ossification between two bones via surgery

Arthrocentesis; puncture into a joint to remove fluid

Articular/Articulated: pertaining to a joint, having a joint, an artificial appendage, limb, joints composed of segments

Articulating: the site of junction or union between bones, especially one that allows free motion of the bones

Artifact: anything not naturally present but introduced by some external source; artificial, manmade product; produced by an external agent or action, such as a structure seen in a microscopic specimen after fixation that is not present in a living tissue; in biochemical blood analysis, some abnormal results are due to disease; those that aren’t related to disease are artifacts. E.g., physiological changes, clinical condition of patient, blood collection method, storage and transport of sample

Artifactual hymolysis: breakdown of red blood cells due to human manipulation

Arytenoid cartilage: one of the paired laryngeal cartilages in the dorsal part of the larynx that provides attachment for the muscles that adduct or abduct the vocal folds.

Ascarids: intestinal parasite, roundworms

Ascites: accumulation of fluid in peritoneal cavity (es-site-eeze)

Ascomycetes: class of fungi containing true yeasts and dermatophytes (skin parasites)

Asepsis: condition in which living pathogenic organisms are absent

Aspergilloma: tumor-like granulomatous mass formed by colonization of aspergillus in the respiratory organs, may disseminate through bloodstream to brain, heart, kidneys

Aspergillosis: fungal infection in respiratory system

Aspergillus fumigatus: causes Aspergillosis; fungus, including molds, caused by dampness

Aspirate: to withdraw fluid from a body cavity using an aspirator or suction syringe, as in withdrawal of blood sample with syringe and needle; to inhale a fluid or foreign body into the bronchi and lungs, often after vomiting

Assay: qualitative or quantitative analysis of a substance, esp drug

Assimilation: conversion of nutritive material into living tissue; anabolism

Asymptomatic: without symptoms but carrying or shedding disease organisms

Asynchronous hatching: single clutch hatches over a period of several days; incubation begins when first egg is laid; Synchronous is all hatch at same time.

Ataxia: loss of coordination in the muscles, esp the extremities, results in staggering gate

Atelectasis: collapsed or airless lung

Atherosclerosis/arteriosclerosis: hardening and narrowing of arteries; causes heart attacks, strokes, peripheral vascular disease; fat and cholesterol plaques form in the intima of arteries; Vascular intima is the innermost coat of a blood vessel.

Atonic: lack of muscle tone

Anopy: hypersensitivity: an allergy with symptoms produced upon exposure to an antigen; inhalant allergies, e.g., pollen or dust

Atoxoplasma: liver enlarged, dark area under skin of abdomen, bloody diarrhea, weight loss, dehydrated, depression, sudden death, “Black spot.”

Atresea/altresic (choanal): the congenital absence of or pathological closure of an opening, passage, or cavity; occlusion or absence of a normal body opening or tubular organ

Atrial fibrillation: atria (chambers of heart that receive blood) contract rapidly, irregularly and independently of the ventricles (chambers that pump the blood). Decreases the efficiency of the heart and its ability to move blood.

Atrial flutter: atria contracts rapidly, irregularly, and independently of the ventricles; this decreases the efficiency of the heart and its ability to move blood.

Atrium/atria: two chambers of the heart that receive blood; right atrium receives blood from body, left receives oxygenated blood from lungs

Atrophic rhinitis inflammation of nose and mucous membranes resulting in degeneration of tissue from nerve damage

Atropine: smooth muscle relaxant, pre-anesthetic

Atrophy: decrease in size or complete wasting of organ, tissue, muscle, cell; suggests reduced innervation

Attenuated: Weakened; an attenuated virus is one that has been changed and will no longer cause disease; used in modified live vaccines

Auditory meatus: ear opening

Auricula: ear area

Auricular coverts/feathers: earpatch, soft, loosely-webbed feathers on side of head to protect ear; overlap the ear, called coverts; no external pinna but have slight thickening of skin around ear

Auscultation: listening through stethoscope to body sounds for diagnosis

Autocthonos flora; normal gut flora, takes 3-4 weeks to develop in chick

Autochthonus: found in original locality; as in disease, found in original place

Autogenous: self-produced, selfgenerated; substances generated in the body

Autogenous vaccine: suspension make from material obtained from lesions of animal to be vaccinated. Used for prevention, amelioration (make better), or treatment of specific infectious disease

Autoimmune disease: body becomes intolerant of its own cells; produces an immunogenic response against self-antigens; One organ is affected, or many tissues

Avascular: lacking blood vessels in body tissue

Avian: Pertaining to birds

Avulsion: tearing away of a structure or part

Axilla/axillary: region under the wing, between the body and the wing; wingpit; underside base of wing extending to ventral wing lining; muscles in the area important to flight, the axilla (refer to Wing Anatomy)

Axillary feathers/Axillars: Feathers located at the underside base of a bird’s wing; the long, stiff covert feathers covering the ventral base of the wing in the “armpit” or axillary area. (refer to Wing Anatomy)

Azotemia: increased nitrogenous waste products in blood as a result of kidney insufficiency/disease

B-Cell: or B-lymphocyte. Produces antibodies, generated in the Bursa of Fabricus; a white blood cell lymphocyte, formed in bone marrow in mammals and present in blood and lymph, that creates antibodies in response to a specific antigen. B cells or B lymphocytes are a type of lymphocyte in the humoral immunity of the adaptive immune system. B cells can be distinguished from other lymphocytes, such as T cells and natural killer cells (NK cells), by the presence of a protein on the B cell’s outer surface known as a B cell receptor (BCR). This specialized receptor protein allows a B cell to bind to a specific antigen. In birds, B cells mature in the bursa of Fabricius (the name of “B” cells comes from the name of this organ).[1] In mammals, immature B cells are formed in the bone marrow.[2]

The principal functions of B cells are to make antibodies to help antigens, to perform the role of antigen-presenting cells (APCs), and to develop into memory B cells after activation by antigen interaction. B cells also release cytokines (proteins), which are used for signaling immune regulatory functions.

Back/interscapular region or dorsum: the dorsal area from the neck to the rump, between the wings

Bacteria/bacterium: one-celled organism, may cause disease, round, rod-shaped, spiral, or filamentous, unicellular or noncellular bodies, often aggregate into colonies; may exist as freeliving organisms in soil, water, organic matter, or as parasites in live bodies of plants; some produce disease, most perform necessary functions such as digestion, fermentation (breakdown of carbohydrates by microorganisms.)

Bacteremia: bacteria in blood

Bacterial loading: normal avian skin contains fewer bacteria than mammals, less need for cleansing

Bactericide/bactericidal: kills vegetative bacteria but not mycobacteria (fungi) or spores

Bacteriostatic: inhibits growth or reproduction of bacterial organisms without necessarily killing them or their spores

Bacteriophage: virus that infects only bacteria

Bacteriuria: bacteria in urine

Barb: parallel feather rays branching out from each side of rachis

Barbicel: hooked projection extending from and interlocking with the barbules of a feather

Barbules: hooked branches extending from each side of feather barb, fasten adjacent barbs together

Barium Study: procedure, pet swallows barium or given as enema, x-ray exams to locate 9 disorder of esophagus, stomach or intestines

Baroreceptor: sensory nerve terminal that is stimulated by changes in pressure, as those in blood vessel walls; reflexes triggered by change in pressure, usually refers to blood pressure

Barraband Paralysis syndrome/spastic Leg paralysis; parrot disease of small number of birds in aviary; presents as sudden onset of paralysis of both legs, from mild weakness to whole limb extending stiffly behind the bird, clenched toes; bird’s general health not affected, eats and behaves normally; cannot balance, is ataxic in more severe cases, walks on hocks or with beak; cause unknown, but calcium, vitamins A, B1,2,6, and E deficiency suspected esp in allseed diets

Bars: Rows of distinctly colored feathers running across the bird’s body

Basal: outer edges of a bill or the outer primaries

Basal cell carcinoma: most common skin cancer; rarely metastasizes or kills, but causes significant destruction and disfigurement by invading tissues; abnormal, uncontrolled growths or lesions that arise in basal cells (deepest layer of epidermis— outmost layer of skin); look like open sores, red patches, pink growths, shiny bumps or scars; caused by UV exposure

Basic plumage: Plumage attained by the prebasic molt

Basilic vein: in upper arm near bicep muscle

Basophil: a leukocyte that cleans up debris

Basophilia: abnormal increase in basophils in blood

Basophilic intranuclear inclusion bodies: white blood cells going to the nucleus of the cell; the bodies are round, oval, or irregularly shaped, in cytoplasm and nucleus, as in viral diseases, e.g., poxvirus

Beak (bill): composed of the maxilla (upper) and mandible (lower); movable in parrots due to elastic zones in facial bones; rasplike ridges run transversely inside maxilla for cracking nuts; dermal and epidermal layers contain calcium and keratin; bill-tip organ, sensitive and used for feeling environment; allows bird to discriminate between food and other particles; nerve endings for mandible are in channels that can be seen as white dots in black beak; never cut them

Beak Overgrowth: Overgrowth of the maxilla or mandible; usually the maxilla (upper beak.) Some birds need their beaks trimmed; Other birds keep their beaks in shape by eating hard foods, grooming, climbing, chewing on wood, and rubbing the beak on a slightly abrasive surface. An overgrown beak can be the result of health problems including trauma, developmental abnormalities, nutritional imbalances, polyomavirus-like infection (finches), or liver disease (especially in budgies).

Beard: line of feathers hanging from a male turkey’s breast

B-cells or lymphocytes: mature in the Bursa of Fabricus in birds; vital part of immune system, specifically the humeral immunity branch of the adaptive immune system; can be distinguished from other lymphocytes such as T-cells and natural killer cells (NK cells) by the presence of a protein on the Bcell’s outer surface known as a Bcell receptor (BCR). This protein allows a B-cell to bind to a specific antigen; its functions are to make antibodies against antigens and develop into memory B cells after activation by antigen interaction. They also have a suppressive function.

Benign: mild illness or nonmalignant tumor; benign tumors have well-defined edges and grow slowly

Beta blockers: Heart meds which block beta receptors in heart; beta receptors receive signals to increase heart rate; if rate is too fast or uneven, beta blockers help stabilize the rate and rhythm of contractions

Beta-carotene: plant pigment which converts to Vt. A

Beta-lactamases: Enzymes produced by some bacteria which inactivate certain types of penicillin; makes the bacteria resistant to them

Bib: colored region seen below the chin of a bird

Bile: yellow-green fluid produced in liver, stored in gallbladder in ratites, stored in small intestine in psittacines; emulsifies fats

Bile acids: only specific test to liver disease in birds; compounds produced by liver are bound to amino acids and excreted in the bile in small intestines to aid in digestion of fats; Most are reabsorbed in small intestine, enter the portal system and are taken up by liver to be recycled; increase in bile acids indicates poor liver function

Biliary duct: related to bile or transport of bile; affecting a bile duct or the system of ducts in the liver

Bilirubin: orange-yellow pigment in bile that is a product erythrocyte breakdown; normally excreted with urine or feces; buildup in body causes jaundice; released by liver in bile

Biliverdinuria: dark green bile in urine indicative of liver disease; increased excretions of it indicate hepatitis; caused by obesity and high-fat diet

Biocide: an agent that kills all pathogenic and non-pathogenic living organisms, including spores; includes insecticides and any compound toxic to living things

Biopsy: removal of small piece of tissue for microscopic exam

Bipedal: stands on 2 legs

Bleaching: lightening of the plumage colors caused by exposure to sunlight

Blepharitis: infected or inflamed eyelid

Blepharospasm: spasm of eyelids resulting in complete closure of eyelids due to pain, e.g., scratched cornea

Blood cells: new cells generated every 4-6 weeks; Low BC due to viral infections; high BC due to stress, disease

Blood feather: new feather has venous and arterial blood supply; thick, purple appearance; as feather matures, blood supply recedes  (Also refer to “Pulling a Blood Feather – Instructions“)

Blood fractionation is the process of fractionating whole blood, or separating it into its component parts. This is typically done by centrifuging the blood. The resulting components are: a clear solution of blood plasma in the upper phase (which can be separated into its own fractions; the buffy coat, which is a thin layer of leukocytes (white blood cells) mixed with platelets in the middle; and erythrocytes (red blood cells)

Blood gases: e.g., oxygen or CO2 in blood

Blood glucose levels: high levels (over 900 mg/dl) cause diabetes mellitus; Below 150 life-threatening

Blood sampling: taken from jugular vein or ulnar vein, not toe clip

Body cavities: hollow spaces that contain and protect internal organs:

• Cranial: protects brain
• Spinal: contains spinal cord in spinal column
• Thoracic or chest: protects heart and lungs between neck and diaphragm
• Abdominal: contains major digestive organs between diaphragm and pelvic cavity
• Peritoneal: hollow space within abdominal cavity between parietal (walls of the) peritoneum and visceral peritoneum
• Pelvic: space that contains the reproductive and some excretory systems (bladder and rectum) and organs bounded by pelvic bones

Bolus: soft, round mass of chewed food; a lump; round mass of medicinal material, larger than a pill; a second, larger dose of medication; also ball of leftover material after ingestion of prey

Bone tissue (Bird): Colored scanning electron micrograph (SEM) of cancellous (spongy) bone from a robin. This tissue, found in the interior of bones, is characterized by a honeycomb arrangement of trabeculae (columns) and spaces. This honeycomb structure provides support and strength to the bone.

Bone callus: localized hyperplasia of the horny layer of the epidermis due to pressure or friction; an unorganized network of woven bone formed about the ends of a broken bone; it is absorbed as repair is complete (provisional callus) and ultimately replaced by true bone (definitive callus); in osteolomy, bony and cartilaginous material forming a connecting bridge across a bone fracture during repair; happens within one to two weeks of surgery

Bone Marrow: soft tissue composed of blood vessels and connective tissues found at center of bones; primary function is blood cell production. Only long bones and some ribs are pneumatic and are filled with air and not marrow. The rest are not pneumatic.   See Appendix / Bird Skeleton

Bone Marrow dysplasia: Myelodysplastic syndrome; preleukemia; a diverse collection of hematological medical conditions that involve ineffective production (or dysplasia) of the myeloid class of blood cells; not a single disease but group of diseases that affect blood cell formation; in all forms of MDS, a bone marrow problem leads to low levels of blood cells circulating in the bloodstream

• Anemia: low level of RBCs
• Leukopenia: low level of WBCs
• Thrombocytopenia: low level of platelets

Bone marrow suppression: cells of bone marrow which produce erythrocytes, leukocytes and platelets are inhibited; a result of certain drugs, such as anti-cancer agents

Booted: not divided into scales (tarsus); the tarsus of certain birds; covered with a continuous, horny, boot-like sheath; having an undivided tarsus covered with a horny sheath

Botulism, type E: the type that targets waterbirds who feed on fish

Brachial: the upper arm; the area supported by the humerus

Brachygnathia: abnormal shortness of the mandible results in maxilla that protrudes

Bradycardia: abnormal slowing of heart rate

Bradypnea: abnormally slow respiration rates

Brain: there are 3 major divisions of the bird’s brain:

• the Optic lobe (chiasma),
• medulla oblongata, and
• olfactory lobe

Branchus/Bronchi: large air passages of lungs

Breast: chest or pectoral region Area of a bird located between the chin and the belly

Bronchitis: inflammation of bronchial passages

Brood: combined nestlings in nest; sitting on/hatching young; sheltering to keep warm and for protection

Brood parasites: Species of birds who deposit their eggs in the nest of other birds, to be fed and raised by other families.

Brood patch: area over breast that becomes thickened, vascular and featherless during brooding period; transfers heat from hen to eggs

Brood reduction: feed most vigorous, biggest ones first; strongest survive in low food supply years, all survive in good years

Bucky technique: set up instrument in line with 2 marks for radiography

Buffy coat: reddish-gray layer of consisting of white blood cells and platelets observed above packed red cells in centrifuged blood; the superficial layer of yellowish or buff coagulated plasma from which the red corpuscles have settled out in slowly coagulated blood

Bulbar: bulb shaped, pertains to medulla oblongata

Bumblefood (pododermatitis) lesions on bottom of feet due to incorrect perching and rough perches

BUN: Blood Urea Nitrogen; blood test that estimates kidney function

Bursa/Bursal: sac-like body cavity, located between moving parts, e.g., elbows, shoulder, knee; fibrous sac that acts as a cushion to ease movement in areas of friction

Bursa of Fabricus:, a specialized organ that is necessary for the immune system. The bursa is an epithelial and lymphoid organ that is found only in birds. It is attached to the large intestine. The bursa is active in young birds. It atrophies after about six months.

C-Fiber: an unmyelinated nerve fiber, esp of autonomic system

Cachectic/cachectin: protein released by activated macrophages as an immune system defense; when it is overwhelmed it causes cachexis or toxic shock

Cachexia: general ill health with emaciation, usually occurring with cancer, chronic infection, disease; extreme weight loss

Calcaneal tendon: Achilles tendon, tendon on tibiotarsus

Calcified: hardening of tissue through the influx of calcium, usually a result of chronic inflammation

Calidridine: group of closely related sandpipers, primarily of the genus Calidris

Callus: bulging deposit around bone fracture; may turn to bone

Cancellous bone: (trabecular or spongy bone); a type of osseous tissue that forms bones. Has a higher surface area than compact bone (other type of osseous tissue), but is less dense, softer, weaker, less stiff; occurs at ends of long bones, proximal to joints and within interior of vertebrae. Cancellous is highly vascular and contains red bone marrow where hematopoiesis (production of blood cells) occurs.  Please refer to: Skeletal System / Bone Anatomy

Candida: genus of yeast; causes disease; infection is candidiasis

Candling / Egg Candling: view of egg for fertility

Cannula: metal tube inserted into body to draw off fluid or deliver medication; tubular shaped, contains trocar (sharp, pointed instrument for piercing)

Canthus/canthi: corners of the eye; inner, nasal, or medial canthus holds the tear ducts, temporal, outer, or lateral canthus is closer to the ear

Cap: top of head, color can differentiate between similar but different species

Capillaria/capillariasis: infestation by nematode : internal parasitic worm

Carcinogen: causes cancerous growths in living tissue

Carcinoma: malignant cancer arising from epithelial tissues, e.g., skin, intestinal tract, bladder

Cardiac failure: weakness, anorexia, tachypnea (rapid breathing), dyspnea (shortness of breath), coughing, abdominal distension due to hepatomegaly and ascites, diagnosis determined by arrhythmia or murmur, x-ray, treatment: furosemide is a loop diuretic (water pill) that prevents your body from absorbing too much salt, allowing the salt to instead be passed in your urine. dose, subcutaneous fluids, oxygen, ultrasound

Cardiac infarction: localized area of necrosis caused by interrupted blood supply to heart

Cardiomegaly: enlarged heart

Cardiomyopathy: heart muscle disease; not of valves or congenital defect; leads to decreased function with no known cause

Cardiopulmonary: of heart and lungs

Cardiovascular system: of heart, blood, blood vessels

Carina: keel bone, sternum, or breast bone. Bone that protrudes a little from the chest

Carotenoids: pigments in the feathers that are derived from the bird’s diet; produce these colors: bright yellow, bright red, orange; occur mostly in flight feathers, back and breast plumage

Carpometacarpus: fused bones of the hand (manus) joint

Carrier: animal harbors infectious organism e.g., virus, bacteria, parasite. Animal appears healthy, but can transmit organism to others by direct contact or release of organisms into environment in stool, urine, respiratory secretions …  Non-shedding carrier: harbors disease but doesn’t show symptoms and is not contagious; as in latent infection

Cartilage: gristly connective tissue, more elastic than bone, used in flexible portions of skeleton. Hyaline, Elastic

Carina or keel; the projection of the breastbone

Caruncle: small, fleshy, comb-like tissue on turkey’s forehead

Caseous: having the appearance of cheese, one of the forms of tissue death (necrosis); e.g., xanthomas

Cast/casting: things that are shed, e.g., skin feathers, can cause renal disease, leftover parts of prey thrown up by raptors, owls

Catabolism: breaking down of muscle or other tissue due to malnutrition or starvation; destructive form of metabolism involving release of energy and resulting in true excretion products

Cataract: cloudiness of lens of eye, reducing vision, giving eye pearly appearance

Catecholamine: organic compound, chemically related neurotransmitters, as epinephrine and dopamine, that have effects on sympathetic nervous system; Some catecholamines are produced naturally by the body and function as key neurologic chemicals; catecholamines play an important role in the body’s physiological response to stress. Their release at sympathetic nerve endings increases the rate and force of muscular contraction of the heart, thereby increasing cardiac output and constricting peripheral blood vessels, resulting in elevated blood pressure, high blood glucose levels, hyperglycemia, lipids; affects metabolism

Celiac: the abdomen or stomach areas

Cell-mediated immunity: a result of special lymphocytes directly killing the foreign invader, or T-Cell lymphocytes releasing special chemicals which activate macrophages to kill the invader; compare with “humeral immunity”

Cell mitosis: cell division

Cellulitis: diffuse inflammation of solid tissue, redness, swelling, pain, loss of function in affected area

Celum/Coelum: principal body cavity of trunk; contains peritoneal, pericardial and pleural sacs

Centrifuge: machine that rapidly spins liquid samples and separates out particles by their density

Cephalic edema: fluid in the head

Cere; fleshy area enclosing nares, smooth, featherless; highly vascularized; found mostly in birds of prey, pigeons and parrots.

Cerebellum: part of brain located on brainstem, controls coordination

Cerebrum: largest portion of brain, performs higher cognitive functions, sits in front part of cranial cavity

Cervical: area and structures of the neck

Cervicocephalic: area of bones of the neck close to the anterior part of head

Cestode: tapeworm parasite

Chalaza/chalazae: gelatinous, milky white, stringy coils of albumen that surround and protect egg yolk; visible at either end of yolk as twisted cords; attached to far ends of eggshell and form a suspension system for the yolk that allows it to rotate throughout embryonic development; stabilizes yolk and keeps it from floating against the upper shell’s surface. Keeps the germinal disk in the upward position so it remains next to the heat produced by the incubating parent above

Cheek: between lore, eye, auricula and mandible

Chelation: binding of a substance to a metal, thus helping the body to remove it

Chemosis: swelling and congestion of the conjunctiva due to edema or circulatory problems; includes excessive secretions and abnormal blood-filled tissue; caused by Chlamydia Psittici

Chest: front of body containing keel and major flight muscles

Chick: the fledglings of certain bird species.

Chin: below beak; does not protrude

Chlamydia/chlamydiophilia psittaci/Chlamydiosis;parrot fever/ornithosis: bacterial organism responsible for psittacosis; gram neg. pathogen; zoonotic, systemic; signs: diarrhea, ocular and nasal discharge

Choana/choanae/choanal: slit in hard palate of mouth, connects nasal passages/cavity with oropharynx; numerous projections or papilla found around edge of choanal slit; glottis fits snugly into the slit when bird closes its mouth to close connection from nostrils to windpipe

Choanal papillae: several tiny whitish projections that line the choanal slit; should be sharp; blunting or absence attributed to hypovitaminosis A or respiratory illness; purpose is to block debris from going up into the choanal

Cholesteatoma: cyst-like mass with lining of stratified, squamous epithelium filled with debris (cholesterol); occurs in brain and CNS.

Cholesteatosis: fatty degeneration due to cholesterol esters (Esters have a very sweet fruity smell.) Naturally occurring esters are found in fruits. An ester is a product of the reaction of an acid (usually organic) and an alcohol.

Chondroitin: it is a molecule that occurs naturally in the body; the major component of cartilage — the tough, connective tissue that cushions the joints; helps keep cartilage healthy by absorbing fluid (particularly water) into the connective tissue. It may also block enzymes that break down cartilage, and it provides the building blocks for the body to produce new cartilage.

Chorioallantoic/chorionic membrane (CAM) forms during embryonic development; lines inner egg shell surface; has capillaries through which oxygen and CO2 gases are exchanged between embryo and outside air.

Chorioretinitis/choroid retinitis: inflammation of the choroid (thin pigmented vascular coat of eye) and retina of eye; signs: floaters, blurred vision, pain/redness, sensitivity to light, excessive tearing;

Choroid/choroidea: middle, vascular coat of eye, between sclera and retina; contains connective tissue and blood vessels; supplies nutrients to inner parts of eye

Christalloid: resembles a crystal; solution containing electrolytes which diffuse into all body fluid compartments; e.g., Ringer’s solution and dextrose in water

CBC: Christmas Bird Count

Chronic: illness of long duration slow progression of symptoms

Chronicity: state of being chronic

Chronic superficial keratitis: chronic eye condition; blood vessels grow across cornea (clear surface of eye); cornea looks hazy and red; eventually takes on dark pigment; aka “pannus”

Cicatrix/cicatrices: fibrous scar tissue left after a wound has healed

Ciliary muscle: striated muscle that controls eyelashes (celia)

Circovirus: causes PBFD

Circumscribed: surround by a boundary or is within a certain space

Cirrhosis: liver disease caused by replacement of damaged cells with connective tissue; severe scarring can eventually cause liver failure; caused by hepatic lipidosis

Cicatrix: a scar resulting from formation and contraction of fibrous tissue in a wound

Cline: a species of birds that is spread out over such a large distance that birds at one end will not associate with the others

Clinical: medical matters e.g., history, signs; also means bird is presenting symptoms

Clinical diagnosis: cause of disease based on physical/visual signs

Clinical study/trial: planned exam of effectiveness of new drug or treatment; as compared to control group not receiving the treatment

Cloaca: common tube-like chamber or structure through which feces, urine, urates, fluids, eggs pass; above vent;

Cloacal Prolapse or everted cloaca: internal tissue turned outward or inside out.

Cloacal compartment: divided with 3 poorly-defined compartments: Copradeum, Urodeum and Proctodeum

Cloacal prolapse: inversion of the cloaca due to muscle weakness, usually from chronic egg laying

Cloacal kiss: copulation; male bird copulates many times to make sure he is father of at least some of the young in his nest

Cloacal papilloma: gross lesion; red proliferative mass commonly originating from just inside the rim of the cloacal opening.

Cloacapexy: incision made in abdomen to suture cloaca to caudal border of sternum (abdominal wall) after prolapse

Cloaca bursa (Bursa of Fabricus): lymphoid gland of cloaca, believed to function in disease resistance, closing or disappearing as bird ages

Cloacal circlet/anal pteryla: the two rows of feathers arranged in concentric circles around the cloaca

Clonic/clonus: alternating involuntary muscle contractions in rapid succession, upper motor nerve disease

Clostridium Perfringen: type birds get; anaerobic, spore-forming bacteria, causes enteritis; both giardia and clostridium cause malabsorption of Vit. E

Clotting factors: protein components in blood which help it clot; clotting is complex mechanism; result of chain of chemical reactions and work of platelets; requires Vit. K

Clutch: complete set of eggs belonging to the female

Cnemial: relating to shin or shin bone

Coagulopathy: a condition affecting the blood’s ability to form a clot; defect in body’s mechanism for blood clotting

Coaptation: joining or adjustment of parts to one another, as broken bone

Cob: male swan

Coccus/cocci: spherical microorganism; any bacterium that has a spherical, ovoid, or generally round shape. It is one of the three distinct bacterial shapes, the other two being bacillus (rodshaped) and spiral-shaped cells; gram-positive, stain purple See Coccidium/coccidia/Coccidiosis protozoan intestinal parasite, lays oocysts (eggs)

Coccidiostat:drug that inhibits growth of coccidia

Cock: male bird

Coliforms: coliform bacillus; various species of bacteria inhabiting colon

Collagen: fibrous, insoluble protein that forms part of the supportive framework of skin, bone, ligaments, cartlage, tendons; also in vitreous humor of eye as stiffening agent

Collar: upper part of neck, behind crown, aka hindneck and nape

Collimate/collimation/collimated beam: radiographic term for adjusting accurately the line of sight

Colloidal solution: semi-solid suspension, uric acid secretion; glue-like solution used to manage shock; increases osmotic pressure and volume of plasma

Colonial: birds of the same species who build multiple nests in colonies

Comb: fleshy skin on rooster’s crown

Commensal relationship: symbiotic relationship in which an organism lives on or within another organism, derives benefit from it, without harming … An example of commensalism: cattle egrets foraging in fields among cattle or other livestock. As cattle, horses and other livestock graze on the field, they cause movements that stir up various insects. As the insects are stirred up, the cattle egrets following the livestock catch and feed upon them. The egrets benefit from this relationship because the livestock have helped them find their meals, while the livestock are typically unaffected by it.

Comminuted fracture: bone fracture in which the separated parts are splintered or fragmented, divided into small parts, powdered or pulverized; at least 3 bone pieces involved

Commissure/commisural point/gape: line formed by meeting of maxilla and mandible; hinge where the two meet; psittacines able to move both but most birds only move mandible

Communal roost: sleeping place for gathering of birds

Compensation: making up for defect of function or structure; e.g., counterbalancing;

Complete Blood Count/CBC: Count of total number of cells in a given amount of blood; includes erythrocytes and leukocytes; tests for abnormalities in blood

Compressed: flatttened from side to side Computerized Tomography Scan (CT or CAT scan): radiological imaging procedure that uses 2-rays to produce “slices” through body; computerized axial tomography.

Concha/conchae: turbinate bone in nose; spongy bones in nasal passages; includes sinuses; hollow spaces in head where infection may clog it with liquid, mucous, abscess, or debris

Concretion: solid, hard mass, lith

Condyle: articular prominence on bone, rounded projection of a bone that anchors muscle ligaments and articulates with adjacent bones; e.g., occipital area (back of head), knuckle, or elbow; smooth surface 15 area at end of a bone, forming part of a joint

Confluent: flowing together, meeting, combining form one

Congeners: something of same type; birds that are related to one another because they belong to same class, group, or type; e.g., animals in same genus

Congenital: present at birth

Conjunctiva: thin membrane which lines inside of eyelids and covers part of eyeball

Conjunctivitis: watery eye discharge, swollen lids, red conjunctiva; paresis, weak jaw tone, mostly in lutinos, inherited, non-infectious

Connective tissue: adds support and structure to body part; holds organs in place and binds parts together … Types: dense connective tissue such as bone, cartilage, tendons and ligaments; loose connective tissue is blood

Conspecific: birds of the same species

Constricted Toe Syndrome

Contact call: sound produced by bird that informs nearby birds of caller’s location; seeking response; by mates or bonded birds to other birds or humans

Contour feathers: the feathers that cover most of the bird, not including the flight feathers

Contrast agents: substance given orally or injected that makes affected tissue easier to identify on x-ray. E.g., barium

Contusion: bruise: unjury to underlying tissues without breaking skin; gives skin greenish color

Cooperative breeding: More than two birds of the same species feeding young birds from one nest

Copralith/fecalith: hard fecal mass

Copradeum: top chanber of cloaca, largest of the three; same as rectum; holds fecal matter until defecation

Copraphagia: eating feces

Coracoid bone: extra bone in shoulder; acts as strut to counterat pressure of downbeat of wings

Cornea: clear part of front of eye, lets light in

Cornified: having a keratinous or horny covering

Cortex: outer layer of bone or organ as opposed to the inner layer; more brittle in birds than mammals

Corticosteroids: natural steroid: hormone produced by adrenal gland and involved in metabolism and immune response; any of the hormones produced by cortex of adrenal glands; also produced synthetically; their action allows many biochemical reactions to proceed at optimum rates. Important to almost every function of cells and organs; Two groups:

• Glucocorticoids –regulate protein, carboydrate, and fat metabolism
• Mineralocorticoids—regulate electrolyte balances

Costal: ribs or rib cage

Cortisol: the main glucocoritcoid: hormone naturally produced by adrenal glands; sythesized as hydrocortisone, used to reduce inflammation

Countersinging: singing of one bird in direct response to another bird singing among the same species

Courtship displays: performace to attract mate, maintain pair bond, stimulate breeding behavior

Coverts (tectrices): smaller feathers covering large wing and tail feathers; partly cover flight feathers; streamlines bird’s profile, reduces frictional drag in flight

Cranial: pertaining to the head

Cranial nerves: birds have 12 pairs of cranial nerves which leave the cranium through special holes in the structure; each innervates a specific area of the body

Craniofacial hinge: hinge at cere allows maxilla and mandible to move at same time; flexible connection between skull bones which permits upper jaw to be raised as same time as mandible is depressed; well developed bwtween the nasal and frontal bones in psittacines

Creche: gathering of hatchlings in a nesting colony, tended to by different adult birds

Crepitant/crepitus: making a cracking crinkly, or grating feeling or sound under the skin, around the lungs, or in the joints. Crepitus in soft tissues is often due to gas, most often air, that has penetrated and infiltrated an area where it should not normally be (for example, in the soft tissues beneath the skin). Crepitus in a joint can indicate cartilage wear in the joint space.

Crepitant rale: cracking sound made during inspirtation in lung diseases

Crepuscular: birds that are active at twilight hours

Crest: tuft of feathers on head; larger in males; increases visibility to predators and potential mates, females evaluate potential mate by his crest; the more elaborate the crest, the healthier the bird is

Crissum: feathers in a triangular area on undersurface of bird between vent and pygostyle; can tell whether a bird is adult or juvenile by cruissum; adult females have dusky edge to most of the featheres there; juvenile females have nearly pure white feathers

Crissom/undertail coverts, or circumcloacal region: the loose feathers that surround the cloaca, including the undertail coverts that cover the ventral base of the tail.

Crop/ingluvies: outpouching of esophagus between cervical and thoracic parts of esolphagus; oreinted transversely across neck

Crop ilius: obstruction Crown: top of head, holds the crest

Cruciate ligament: cross-shaped

Crural feathers: on femoral tract which covers outer surface of thigh in a diagonal strip from knee joint upward toward pygostyle; rest of leg contour feathers are included within the crural tract.In some large birds and in birds with heavily feathered legs, additional metatarsal tract is identified, covering tarsometatarsal area of lower leg

Crust: area of dried fluid or cells on skin; may be blood, serum, pus, or medication

Cryptic: a bird’s plumage that is able to blend into the local surroundings or habitat

Crystalloids: crystal-like, forms solutions that can pass through semi-permeable membranes as in dialysis; opposite of colloid which does not dissolve and does not form a true solution; given for shock, contains electrolytes and non-electroytes which will diffuse in all body compartments; e.g., Ringer’s solution and 5% dextrose in water

Culmen: uppermost central ridge of maxilla; no specific function: males’ are larger

Culture: propagation of microorganisms or living tissue cells in media conducive to growth or reproduction

Curette: surgical tool for cleaning nares and other procedures

Cutaneous: relating to skin

Cyanosis: blue-gray or purple discoloration of skin and/or mucous membranes; caused by deficiency of oxygen and excess of carbon dioxide in blood; due to heart disease, obstruction of airways, or certain drugs’ overdose

Cycle: the yearly cycles a bird will have to mature before developing adult plumage

Cygnet: young swan

Cyst: abnormal mass under skin surface; abnormal sac-like structure lined with cells which produce a liquid, thick material

Cystadenomas: benign cystic tumor or neoplasm that exhibits glandular differentiation: cystoma plus adenoma;

Cystectomy: removeal of urinary bladder

Cystitis: inflammation of urinary bladder

Cystocentesis: procedure to obtain uncontaminated urine sample; needle is passed through abdomen into bladder, urine is collected in a syringe

Cystopexy: fixing urinary bladder to abdominal wall

Cytoplasty: repair of uninary bladder.

Cystotomy: surgical incission into urinary bladder

Cytokines: any of a group of small, short-lived proteins that are released by one cell to regulate the function of another cell, thereby serving as intercellular chemical messengers.

Cytokines effect changes in cellular behavior that are important in a number of physiological processes, including reproduction, growth and development, and injury repair. However, they are probably best known for the roles they play in the immune system’s defense against disease-causing organisms.  Compounds produced by certain cells act as messengers to control the action of lymphocytes and other cells in an immune response

Cytology: study of microscopic appearance of cells, esp to diagnose abnormalities and malignancies; often refers to microscopic examination of a sample taken from skin or lesion to find cause for the condition

Cytoplasm: thick substance surrounding the nucleus of a cell; is the physical basis of all living activities in the body

Cytoplasmic: refers to the protoplasm surrounding the nuclus of a cell

Cytosis: act of destroying cells

Cytotoxic: poisonous to cells

Dabbling: waterfowl’s method of using the bill along the surface of the water to screen for food

Deaminate: to remove the amino group from a compound

Debillitation: weakening of body

Debridement: removal of foreign matter and dead tissue from a wound 

Decompensation: inability of diseased organ to compensate for its defect; failure of body to make up for defects of function or structure

Decubitus: any position taken by lying in bed

Decubitus ulcer: pressure or bed sore; produced by local interference with circulation; usually occurs over a bony prominence, such as sacrum, hip, heel, shoulder, or elbow; caused by excessive/prolonged pressure produced by weight of body or limb

Decurved: a bill that is curved downward toward tip, like a curlew’s

Decussation: bands of nerve fibers crossing, passing between centers on opposite sides of CNS, X-shaped

Deficiencies:

• Argonine: results in curled wing feathers
• Riboflavin: clubbed down feathers
• Pantothenic Acid: (niacin and selenium) poor feathering; see “Nutritional Requirements of Parrots” in Beauty of Birds

Definitive diagnosis: scientific identification of cause of disease

Dehiscence: bursting open, as of contents; incision dehiscence: opening of an organ to discharge its contents; parting of the lips of a surgical wound

Dermatitis: inflammed skin

Dermatome: area of skin supplied with afferent nerve fibers by a single dorsal spinal root; A dermatome is an area of skin that is mainly supplied by a single spinal nerve; The surface of the skin is divided into specific areas called dermatomes,” which are derived from the cells of a somite. They are necessary for assessing and diagnosing the level of spinal cord injury. These cells differentiate into the following 3 regions:

1. myotome, which forms some of the skeletal muscle
2. dermatome: which forms connective tissues, including the dermis
3. sclerotome, which gives rise to the vertebrae.

Desertion: abondoning the nest

Desiccation: drying out

Desquamation: to remove, scale or peel off in small pieces, esp skin; can be naturally occurring

Detritis: (cellular) particulate matter produced by or remaining after the wearing away or disintegration of a substance or tissue

Diabetes mellitus: metabolic disease caused by failure of pancreas to produce insulin (glucogen for birds) , a hormone that allows blood sugar (glucose) to be taken up by cells that require it to function

Diagnostic feathers: the particular feathers that determine the species of the bird

Diaphysis

Dia’physis/diaphy’sial: shaft of long bone, between the ends, to grow between

Diarrhea: abnormally fluid-laden fecal discharge; result is poor absorption of water, nutritive elements and electrolytes

Diasthesis: unusual susceptibility or predisposition to a disease

Dichromatism: the normal occurrence of two different colorations in the same species due to neither sex nor age

Differential diagnosis: all the possible diseases that could be causing the symptoms

Differential WBC: Percentage of different types of white blood cells in a sample

Differentiate: marked or formed differently from other cells; distinct; changed from a generalized form into a form specialized for a tissue, organ or other body part

Diffuse: not limited or localized, spread widely

Digitegrade: walks on toes rather

Digits: the fingers; in birds, the remnants of four digits are present than all foot bones

Dihedral: wings held in V-shape profile while in flight/gliding

Dilated cardiomyopathy: heart enlarges but heart muscle thins

Dimorphis/dimorphic: physical characteristics which differentiate male from female; distinct difference in plumage or color

Diphtheritic lesions: lesions in membranes which resemble human diphtheritic lesions; formed in air passages, esp throat, necrosis of superficial layers of mucosa combined with inflammatory exudate on mucosa

Discrete: separate, unconnected parts, not spread out, limited to one area

Disseminated: scattered, distributed over an area

Disseminated Intravascular coagulation: DIC: hemorrhagic disorder that occurs following the uncontrolled activation of clotting factors and fibrinolytic enzymes through small blood vessels; results in tissue necrosis, bleeding, death

Distal Band (aka subterminal band = the stripes on the tails of certain birds. The stripe is located just before the tip.) 

Distal or superior umbilicus: area by the afterfeather. Proximal 18 or inferior umbilicus is the part going into the feather follicle.

Distraction display: shown by the parent bird to attract predator away from nest.

Diuresis: increased urination caused by excessive intake of fluids, or a drug; unusually large urine output

Diurnal: birds that feed during daylight hours.

Diverticulum: circumscribed pouch or sac occurring naturally, usually in reference to the colon

Diverticulum in bones: air sacs that extend into the long bones, making them pneumatic or air-filled

Down feathers: soft, fluffy feathers whose barbs do not cling together; they trap more air and provide extra insulation; young birds have natal down before molting into their juvenile plumage; protects skin from moisture and pathogens

Drake: male of some species

Drift: polyethyline intermedullary bone fixation appliance; also viral drift–gentotypes

Dry eye: Keratoconjunctivitis Sicca (KCS); occurs due to inadequate tear production; includes thick, yellowish discharge from eye.  Also refer to Eye Diseases

Dump nesting: laying eggs in nests of other birds, usually the same species

Duodenum: top part of small intestine from pylorus to liver; accepts bile and pancreatic fluids then joins large intestine

Dyschezia: difficulty defecating

Dyscoria: abnormal shape or form of pupil or reaction of two pupils

Dyscrasia: unspecified blood disorder; morbid general state resulting from presence of abnormal material in the blood; usually seen with disease affecting blood cells or platelets. Present with a WBC of over a million.

Dysgerminoma: solid malignant ovarian neoplasm derived from undifferentiated germinal cells

Dyspharyx: proventricular worm/parasite

Dysphagia: difficulty swallowing or eating

Dysplasia: abnormal growth of cells, tissues, organs

Dyspnea: difficult or labored breathing

Dystocia: inability to pass egg

Dystrophic/dystrophy: defective growth in size of an organ, tissue or cell; due to faulty or inadequate nutrition or development; weakening degeneration or abnormal development of muscle; muscles atrophy

Dysuria: difficult/painful urination

Ears: facial discs, auricular meatus; rounded areas on cheek

Ear canal: tube that connects external ear with ear durm

Ear coverts: feathers covering the birds ears (see auricular coverts)

Ear drum: tympanic membrane, divides inner from outer ear; prevents infection from reaching inner ear; vibrates to amplify sounds

Eccymosis/eccymotic: swelling due to blood extravasation (escape into tissues); bruising, swelling on skin due to hemorrhage

ECG/EKG: Electrocardiogram; printout of analysis of electrical activity in heart; electrocardiography: graphic recording of the electrical actiivity of the heart, allows heart muscle action to be studied

Echocardiogram: image produce by performing ultrasound of heart

Echogenic: capable of generating or reflecting soundwaves, as in tests

E-coli: common gram-neg pathogen in birds; enteric bacteria; normal in some birds in small amounts; produces toxins/disease

Eclipse plumage: non-breeding plumage

Ectoparasites: flies, ticks, fleas, lice; inhabit exterior of host’s body

Ectropion: abnormal distortion of eyelid so that lower lid turns out, causing a pocket in which tears collect and run out

Edema/edematous: excessive accumulation of serous fluids in an organ,body cavity, or tissues; causes swelling (hyperemia)

Efficacious: effectiveness

Effusion: lymph or blood present in body cavities or tissues; a result of inflammation

Egg: ovum before and after fertilization; contains embryo, yolk, albumin

Egg callosity: egg tooth

Egg laying (chronic) and egg binding: caused by obesity, low calcium levels, chilling, lack of exercise, infection in oviduct; bird straining to pass egg; erect posture, swollen abdomen, egg palpable near vent; most common in hens with no mate

Egg tooth: short, pointed, calcareious (contains calcium 19 carbonate) structure on tip of maxilla that develops shortly before hatching; used to break out of shell; sloughs off or is reabsorbed within a few days after hatching

Electrocautery: electric instrument with very hot tip; applied to a tissue to make incision, remove a mass or stop bleeding

Electrolyte: a substanced in a solution; in body fluids

Electromyography (-gram): records electrical activity of muscle cells, records strength of muscle contraction; caused by electrical stimulation

Electrophoresis: process used in separation of proteins and nucleic acids; used to study diseases in which there are altered serum and plasma proteins

Elemental formulas: high caloric, protein fat and carb content; high osmolality, vary from requiring some digestion to requiring little to none (monomeric); formula is predigested (proteins hydrolyzed)

ELISA-A: fluorescent antibody serology test that detects diseases such as psittacosis, ABV/PDD; enzyme on a substrate pulls out blood serum; positive birds shed the organism only about 12% of the time, so neg does not rule out Psittacosis

Emaciation: loss of flesh through disease or starvation; severe weight loss resulting in 50% of normal weight

Emarginate: notched tail faither

Embarrassment: difficulty in function due to disease; failure or impairment of functioning; to interfere with or impede an organ or part;, e.g., fetal or respiratory embarrassment; distress; physiological difficulty of some kind

Embolic: the lodging of an embolus which may be a blood clot, a fat globule or a gas bubble in the bloodstream; can cause a blockage.

Embolism: sudden blocking of artery by a clot; brought to site by blood flow

Embryo: developing bird in egg

Embryonic development: biochemical processes, programmed by DNA, that take place within the egg through which a fertilized egg develops the specialized tissues and organs

Emesis: vomiting

Empirical: derived from or guided by and provable by experience or experiment alone, without using scientific method or theory, esp as in medicine; evidence that can be observed

Emulsion: mixture consisting of a solid or semisolid dispersed in a liquid

Encephalitis: inflammation of brain, often caused by virus

Encapsulated: enclosed by a protective coating or membrane, e.g., encapsulated bacterium, organ structure; fatty, cartilaginous or fibrous structure enclosing a part

Encephalopathy: degenerative brain disease; severe hepatic insufficiency, causes excitability, tremors, compulsive walking, head pressing, apparent blindness, coma, convusions, death

Endemic: found in a specific area or species; present in a community or among a group; birds that are only found in certain states or countries; disease prevailing continually in a region

Endocarditis: inflammation of endociardium (serous membrane that lines the cavities of the heart)

Endocrine gland: ductless gland which produces an internal secretion that is discharged directly into the blood or lymph and circulated to all parts of the body

Endogenous: produced or synthesized or caused by factors within the organism or system

Endoparasite: invertebrate or protozoan parasites that inhabit interior of host’s body or skin’s surface

Endophthalmos: sunken eye, backward displacement of eye in bony socket, caused by traumatic injury or developmental defect

Endoscope/endoscopy: long, flexible tube with lighted mirror and lens system attached (cannula); passed through body to view organs; uses fiberoptics: surgical procedure

Endosteal/Endostium: tissue lining of medullary cavity of a bone

Endotoxin: bacteria confined within body of bacterium and freed only when the bacterium disintegrates

Endotracheal tube: placed into trachea to allow oxygen and gases to be breathed into lungs

Enteral: pertaining to intestines

Enteral feeding: tube feeding through skin into intestine; allows nutrition to be forced into intestine

Enteric bacteria: normal or pathogenic flora in intestines

Enteric nervous system: (ENS) or intrinsic nervous system is one of the main divisions of the autonomic nervous system and consists of a mesh-like system of neurons that governs the function of the gastrointestinal system

Enteritis: intestinal inflammation/infection, esp small intestine

Enterobacteria: gram neg pathogen, mild

Enucleate/enucleation: to remove without cutting into the organ or mass; e.g., eyeball or tumor

Enveloped virus: covering of a protein capsid; can cause persistent infections; doesn’t live long outside of host; can change rapidly to evade immune system

Enzootic: diseases afflicting all animals in particular area

Enzyme: protein produced by cells which cause chemical changes in other cells but are not changed themselves; regulate production of chemical substances in body

Eosinophil/eosinophilic: granular white blood cell stained with eosin, elevated with parasites, allergies, tissue inflammation

Eosinophilia: more than usual number of eosinophils in circulating blood

Ependyma: epithelial membrane lining the ventricles of brain and canals of spinal cord

Ependimoma: a glioma (tumor arising from neuroglia) arising in or near ependyma

Epicardial: tissue around the heart

Epidermis: top layer of skin

Epidemic: disease attacking many in community simultaneously; introduced from outside

Epidemiology: study of factors involved in diseases in a community

Epiphora: excess tears in lachrymal glands due to obstruction of gland

Epiphysis/epiphyte: end of long bone, wider than the shaft, all cartilage, separated from shaft by a cartilaginous disk

Epistasis: stoppage of secretion or discharge; e.g., nose bleed, hematoma, tumor or swelling containg blood

Epistaxis: nose bleed

Epithelium/epithelial: membranous tissue composed of one or more layers of cells that cover most internal and external surfaces of body and organs; layer between an organism and its tissues or organs and their environment (e.g., skin cells, inner linings of lungs or digestive organs, outer lining of kidneys); encloses and protects a body part; forms essential part of the sense organs

Epithelial surfaces: skin, mucosal linings of internal organs

Epithelial tissue: Covers internal and external body surfaces … Types:

• Mesothelium: tissue covering internal organs and blood vessels
• Endothelium: covers serous membranes, such as peritoneum

Epitope/antigenic determinant; determines which antigen is attacking the body; part of antigen that is recognized by the immune system, specifically by anitbodies, B-cells, T-cells.

Epizootic: diseases that spread quilckly among animals

Erector muscles: raise feathers for cooling, shaping

Ergot poisoning: fungus in cereal grains

Erythema: redness of skin caused by blood clogging in small blood vessels

Erythrocyte: (avian) red blood cell consisting largely of hemoglobin and carrying nearly all the oxygen containing in the blood; manufactured in bone marrow

Eschar (es’kar): hard crust or scab as from a burn; deep cutaneous slough such as from a thermal burn, corrosive action or decubitus ulcer

Esophagus: connects to crop then travels through bones at top of keel to connect to proventriculus

Esters: chemical combination of an alcohol and acid; fragrant flavors used in foods and perfumes

Etiology: origin or cause of a disease

Euthanasia: causing death humanely and painlessly to end suffering

Eutocia: ease of delivering eggs

Eutrophic (eutrophia): state of good nutrition

Euvolemia normal blood fluid volume Evert: turn out, as eyelid

Eviscerate: remove or expose internal organs, esp after unsuccessful surgical closure of abdomen

Excoriation: injury to surface of body caused by trauma, e.g., scratching, abrasion, chemical or thermal burn; superficial abrasions which remove some of the skin; caused in animals by rubbing or scratching pruritic skin

Excrete: to separate and eliminate from an organ; expel from blood or tissues; waste matter

Excretory urography: radiographic imaging of urinary tract for diagnosis

Excursions: range of movement regularly repeated in performance of a function; e.g., excursion of the jaws in chewing, thoracic movements

Exocrine: secreting through a duct, e.g., exocrine gland

Exocrine pancreatic insufficiency: not enough fluid being secreted through pancreatic duct

Exophthalmus/exophthalmia or proptosis: protrusion or bulging of the eyeball from the orbit due to papilloma or disease, esp hyperthyroidism, or injury, sinus infection, thyroid disease or trauma

Exostosis/exostoses: benign new growth projecting from bone surface and capped with cartilage because of excess calcium forming; Exostoses can cause chronic pain ranging from mild to debilitatingly severe, depending on the shape, size, and location of the lesion. It is most commonly found in places like the ribs, where small bone growths form, but sometimes larger growths can grow on places like the ankles, knees, shoulders, elbows and hips. Very rarely are they on the skull. They normally form on the joints of bones and can grow upwards. For example, if an extra bone formed on the ankle, it might grow up to the shin.

Exotic bird: one that is tropical or non-native to North America

Exotoxin: toxin or poison produced by bacterial microorganism and excreted into its surrounding tissue

Exsanguination: pulling/sucking blood to drain the blood; bleed to death; deprive of blood

Extant: still in existence

Extensor rigidity: muscles contract and straighten the limb, preventing it from relaxing

Exterpated: killed off or destroyed from a certain region, state or country

Extracellular: occurring outside a cell

Extracranial: occurring outside the skull

Extrahepatic: occurring outside the liver

Extraluminal/intraluminal: lighting from without, from within; intraluminal fluid lights up body masses

Extrapair paternity: young in the nest fathered by a bird other than resident male

Extravasation: discharge or escape, as of blood, from a vessel into the tissue

Extrinsic: existing outside the anatomical limits of a part, e.g, certain muscles or nerves

Extrinsic mass: existing on or outside a part

Exudate/exude: matter coming from a part, e.g., nose, uropygial gland; discharge slowly, accumulation of fluid, protein, and cellular debris in a cavity; matter penetrates through vessel walls into adjoining tissue or outside; production of pus or serum coming out slowly, ooze out through small openings, pores, like sweat

Exuviate: cast off, molt

Eye: larger than humans’ proportionally and larger compared to skull; take up about 15% of head mass and weight; lighter compared to human skull

Eye crescents: contrasting white crescents seen above and below the eye of the bird

Eye deformity (congenital): incomplete separation of eyelids, narrow eyelids, mostly in lutinos, surgery not usually successful

Eye line: line of feathers just in front of and behind the eyes; extends back from the posterior angle of eye

Eye ring: pale ring of feathers encircling the eye; narrow, not clear from a distance; separates the eye from the face feathers; not all birds have them

Eyebrow: arch of feathers growing overtop the bony arch of each eye, similar to human eyebrow; supercillium or superciliary line

Eyelid: one upper and one lower lid; lower more moveable;

Eye stripe: see “supercilium”

Fall molt: aka winter plumage, fall plumage or basic plumage

False negative/positive: diagnostic test reads incorrectly

Fascia: layer of condensed connective tissue which covers, unsheaths, supports, or binds together internal body parts or structures; continuous with other connective tissue structures such as ligaments, tendons, periosteum

Fasciitis: inflammation of fascia

Fat deposits; found in abdomen of birds, not breast; yellowish deposits cranial to vent under the skin; sometimes found cranial to pygostyle

Feather: keratinous structure made of protein and covering body; lightweight and strong, protects skin, enables flight, used to attract mate, waterproofs body, prevents pathogens from entering through skin

Feather numbering: numbering system which assigns a number to each primary feather for identification; primaries are counted from radiale/ulnare (#1) to the alula (#10); secondaries are counted from the manus joint to the humerus, 1-18 

Feather cysts: swellings on body wall, wings or tail; caused by feather growing in or under skin instead of out of follicle; genetic or due to injury to feather follicle, malnutrition, parasites, viral or bacterial infections; treatment is surgery to remove feather follicle; most often seen in macaws and canaries

Feather Duster disease: a rare mutation in budgies; impaired growth, short life span; feathers grow in curls without stopping

Feather dystrophy:

• Clinical signs: parakeratosis, hyperkeratosis, feather defects (stress marks), scaliness of apteria, pruritis, persistent feather sheaths
   
• Causes:
  • Malnutrition: causes hyperkeratosis, results in feather loss due to hypovitaminosis A and loss of pigmentation, and parakeratosis from pantothenic acid deficiency
  • Iodine deficiency: results in hypothyroidism
  • Heavy endoparasitic infection: retards absorption of nutrients
  • Vitamin deficiencies, esp Vit. B

Feather Follicle: group of cells in the skin from which feathers develop

Feather sheath: thin, cylindrical tube of keratin surrounding and protecting developing feather; breaks open when feather matures to let feather unfurl

Feather structure: Feathers are composed of starch, nucleic acids, protein, and lipids.

Feather tracts: pterylae, areas of skin where follicles lay

Fecal Floatation: test that floats parasite or worm eggs so they can be seen under a microscope; feces mixed with chemical solution, spun in centrifuge, and the fluid lying above the feces at the bottom of the test tube is drawn off, stained, and examined

Fecal sac: the sac enclosing the feces of nestling birds; the parent removes it and keeps the nest clean

Fecal smear: feces smeared on slide; determines parasites, bacteria, fungi, protozoa

Feces: solid body waste from intestines

Feet: located at terminal part of legs; most have four toes; hallux (first toe) points backwards, others forward; 2,3, 4 digits counted from inside of the foot out; in parrots, two front toes, two back

Femoral: pertaining to or located in femur/thigh

Fibrin: white, insoluble fibrous protein essential to blood clotting

Fibrinogen: protein in blood plasma that converts to fibrin; fibrin threads form a meshwork for the basis of a blood clot; fibrogen is formed in the liver

Fibroblast: immature fiberproducing cell that is capable of differentiating into a cell that can produce collagen, bone or cartilage

Fibrocartilage: articular, covers joint surfaces of bone; e.g., meniscus: curved fibrous cartilage found in joints, cushions forces applied to joint

Fibrocartilaginous callus: forms between broken bones

Fibroma/fibroid: tumor composed of fully developed connective tissue

Fibronecrotic lesion: lesion covered with thick, yellow membrane composed of exudate and firmly attached to the tissue beneath

Fibrosarcoma: sarcoma (cancer) arising from collagen-produced fibroblasts

Field marks: visible signs on a bird which will allow ease in identification

Filamentous: long and slender; microbiology; very long strand of similar cells joined end-to-end, as in some bacteria and algae

Filarial/Filariasis: parasitic tropical disease; referring to, infected with, transmitted by or caused by thread-like nematodes (roundworms)

Filoplumes: hair-like feathers with no vein and small tuft at top

Fine-needle aspirate: suction applied to hollow needle inserted into tissue; a core of tissue is withdrawn to culture or examine microscopically

First generation: medications developed from an earlier form of medication; developed from original form of the drug; second generation meds are adaptations of the first generation, etc.

First intention (primary union): manner of healing: occurs when surgical incision or cut heals immediately; restoration of tissue continuity occurs directly, without granulation; union of skin edges heal quickly

Fistula: narrow passage or duct formed by disease or injury, as one leading from an abscess to free surface, one cavity to another, or opening made into hollow organ, e.g., eyeball or bladder, for draining; suppurative inflammation; tube-like pasage within body tissues, usually between two internal organs or from organ to body surface; Some created surgically; permits passage of fluids, pus, secretions, or saliva

Flagella: whiplike appendages on certain bacteria and protozoa

Flange (oral): brightly colored enlargements around base of neonate’s beak; extends from corner of mouth and tapers toward tip of beak; supplied with tactile nerve endings; parent feeding young touches flange, mouth springs open, bright colors help parents place food properly

Flank: visible sides of the bird seen below the wings

Fledge: the act of a young bird leaving the nest

Fledging/Feldgling: baby bird out of nest but unable to fly or feed itself without parents; process of leaving nest; premature fledging: baby leaves nest before it is developmentally ready, usually dies

Flight feathers: remiges, rectrices, tertials and secondaries; remiges, long, stiff feathers attached to bones of wing; two groups: primaries and secondaries; involved in propelling and steering; attached directly into periostium (bone); rectrices (tail feathers); body feathers originate in skin

Floaters: birds that do not hold territories or form pair bonds but travel to areas containing territorial birds, waiting to take over territory or nest, copulate with a paired bird

Flocculating agent: substance/chemical capable of penetrating another substance; results in one being suspended in other

Flock: a group of similar birds

Flora: (intestinal) bacteria normally found in intestines

Fluroscope/fluorscopy: instrument with which x-ray images of the body can be viewed directy on the screen; used to monitor motility of GI tract, joint or organ systems in movement

Focal limited to small area or volume

Fomite: a pathogen-contaminated object that can transfer a pathogen from host to another person/animal; e.g., a computer keyboard used by multiple people

Foramen: a natural opening or cavity in a human or animal body, usually one through which blood vessels and nerves pass through bone

Forehead/frontal region: area above eyes and cere

Foreign antigens: antigens unlike the self; autoimmune disease occurs when body becomes intolerant of its own cells

Foreneck: throat, front of neck; jugulum (throat patch)

Fossa: a hollow, pit, or groove in a part of the body such as in a bone

Foveas: particularly sensitive spots in the retina

Fracture: break in a bone caused by trauma, twisting, weakening of bone structure due to disease or injury

Frank blood: bright red blood in stool from hemorrhoid or anal fissures; on surface of stool, not digested; Black, tarry stool: is digested blood

Free radicals: natural byproducts of oxygen metabolism that may contribute to development of chronic diseases, e.g., cancer, heart disease

Friable: readily crumbled, brittle, easily reduced to tiny particles, fragile; e/g., damaged skin

Friction rubs: found upon ascultation; rubbing together of 2 inflamed surfaces, e.g., pruritic friction rubs; in birds, lung and air sac noises and friction rubs could indicate air sacculitis

Frontal shield: An extension running from the upper beak to the forehead

Fulguration: surgical destruction of tissue, e.g., feather cysts

Fundus: the bottom or base of an organ; the part of a hollow organ farthest from the opening; e.g., retina of eye

Fungicide: chemical that kills fungi

Fungus/fungi: low forms of plant life; widespread in nature; unable to form protein and carohydrates; larger than bacterial cells; nucleus and vacuoles can be seen through microscope; major groups are yeasts and molds; infect body, skin, feather follicles; treated with oral and/or topical antifungal

Furcula: fused clavicle or collarbone; aka wishbone; springlike connection between shoulder joints; clavicles fuse ventrally to form furcula; fused at the ends to form a V-shape

Furosemide is a loop diuretic (water pill) that prevents the body from absorbing too much salt, allowing the salt to instead be passed in the urine.

Gaggle: flock of geese or sound given by a goose

Gallinaceous birds: pheasants, chickens, turkeys, waterfowl

Gamete: one or two cells, sperm or ovum, whose union is necessary in sexual reproduction to initate development of new individual; term also used for parasitic organisms

Gametocyte: cell that produces gametes; an oocyte or spermatocyte

Gander: male goose

Ganglion/ganglia: a knot or knotlike mass; general term to designate a group of nerve cell bodies located outside centeral nervous system

Ganglioneuritis: sensory ganglionitis or ganglioneuritis: rare problem in which sensory dorsal root ganglia as well as sensory nerve endings connected to them are damaged; the result of inflammation caused by underlying illnesses; results in spontaneous random movements of limbs and proprioceptive defects; poor prognosis; can be halted if found before irreversible damage occurs

Gape: the mouth lining or margin at the corner where the two mandibles intersect (commissure); also to gape is to open the mouth wide, stretching the commissure. This is done when bird is thirsty or has something in its throat.

Gapeworm: roundworm that lodges in respiratory passages; rare in pet birds; most often seen in exotic galliforms

Gaping: begging behavior of young birds, begins shortly after hatching; widely opened mouth; adult birds can gape for air

Gastric lavage: flush out the crop

Gastroenteritis: inflammation of lining of stomach and intestinal track; symptoms are vomiting and diarrhea

Genetic disorder: inherited, defective genes

Genotypes: group of organisms having the same genetic construction; viruses can have multiple genotypes or mutations Aka viral drift

Genus: level of classification between “species” and “family”

Germinal spot/disk: light-colored site on egg yolk where embryo will eventually develop

Germinative layers: earliest stages of development, deepest layers

Giardia/giardiasis /Giardia lamblia: the parasite causing intestinal infection; a genus of anaerobic flagellated protozoan that colonize and reproduce in small intestines; leads to malabsorption of Vit. E; Oocytes (dropped cysts) eaten by other birds during copraphagia and passed on; exists in filth, causes diarrhea, weight loss, malabsorption deficiency disease.

Symptoms: feather picking, selfmutilation, screaming, cow-pie feces, passing undigested foods, failure to thrive, strong malodor

Gizzard: organ in the digestive tract of birds who eat seeds whole; comparable to ventriculus in psittacine family

Gland: secretes material used elsewhere in the body The only true glands of the integument in birds include the uropygial gland, sebaceous glands of the ear canal that secrete a waxy material, and glands of the vent that secrete mucus.

Glaucoma: increased pressure within the eye, caused by accumulation of fluids; leads to blindness

Glenoid cavity: (pit or socket), a depression in the ventral angle of the scapula for articulation with the humorus

Globoid: global or round shape, having globules

Glubulins: simple proteins that are insoluble in pure water

Glomerulitis: inflammation of nerves or blood vessels of kidney

Glomerulonephritis (GN): aka glomerular nephritis; renal disease; inflammation of glomeruli, or small blood vessels in kidneys

Glomerulophathy: set of diseases affecting the glomeruli of the nephron (kidney)

Glomerulus: area of blood filtering in the kidney

Glottis: opening to windpipe at upper part of trachea, closes during swallowing, allowing the food to pass into the esophagus at base of tongue

Glucocorticoid: hormones produced by adrenal gland to regulate protein, carbohydrates and fat metabolism; glucocorticosteroids stabilize cell membranes as they function in treating allergic reactions

Glucogen: in birds, pancreatic hormone needed for glucose to be used for energy in cells; birds do not produce insulin

Glucogen resistance: blood glucose level remains higher than it should

Glucosamine: substance the body makes and uses to form new cartilage

Glucose: simple sugar in foods, esp fruit; found in blood, major source of energy

Glucosuria/glycosuria: glucose in the urine

Glycogen: storage form of glucose in the body

Going light: losing weight

Goitogens: goiter-producing substances

Gonads: primary sex organs, testes and ovary

Gonydeal spot: reddish spot around the gonydeal expansion on the lower mandible of a gull

Gonys (go’nis): central midline ridge running from the tip of the lower beak back to the anterior end of the head; along the tip of the lower mandible of bird’s bill, at junction of the two joined halves, esp prominent in gulls

Gorget: area of iridescent feathers found about the head and neck of most male hummingbirds and some females

Gosling: young goose

Guano: bird excrement in the crystalline form of surplus nitrogen known as uric acid

Gout: kidneys malfunction; urates built up in blood and are deposited into joints (articular) and around heart, liver and organs inside body (visceral). Nitrogen is major waste product in urates, give it white, pasty look; when kidneys don’t function well, urates are built up in blood and deposited into joints and around organs;

• Symptoms: depression, lameness, joint swelling, redness, white nodules in joints
• Cause: old age, advanced kidney disease, severe dehydration
• Diagnosed by urine and blood tests
• Treatment: fluid therapy, electrolyte therapy; allopurinol dissolves urates and aids in excretion; poor prognosis

Graduated: feathers successively shorter from center to outside as in tail and longer from body to alula (wings)

Gram: measure of weight; 28 grams=1 ounce; 454 grams=1 lb

Gram’s stain: method of differential staining of bacteria; gram positive bacteria stains violet, gram negative stains red or pink; staining quality is based on structure of cell wall surrounding the bacteria. This structure of the cell wall influences which antibiotics will kill the bacteria

Granulated tissue: having a grainy texture

Granulation/Granule: division of a hard substance into small particles (granules); the formation in wounds of small, rounded masses of tissue during healing

Granulocyte: any cell containing granules, esp a granular leukocyte

Granuloma: a tumor-like mass or nodule consisting of actively growing capillary buds, fibroblasts and white blood cells; caused by chronic inflammation/infectious disease/invasion of a foreign body, or by healing process of large, gaping wound; marked by formation of granulations associated with infection; can’t be spread to other birds or mammals; it’s an infection

Granulomatous dermatitis: Genetic, chronic disease; immune system phagocytes malfunction, leading to ongoing, severe infection; rare; white cells accumulate in epidermis, esp around follicles;

• Signs: red/flesh colored palpable small lesions on face; may be scales, pustules, pruitis;
• Treatment: antibiotics,e.g., metronidazole, erythromycin, doxycycline

Granulomatous tissue in wound healing: new connective tissue and tiny blood vessels that form on the surfaces of a wound during the healing process.

Granulation tissue typically grows from the base of a wound and is able to fill wounds of almost any size.

Granulosa cell tumors: ovarian stromal cell tumor originating in solid mass of granular cells that surrounds ovum in developing follicle; caused by excessive production of estrogen

Greater secondary coverts: feathers overlying the bases of the secondaries; in some birds the primary coverts are completely covered by them

Guild: flock of birds, including different species, which share the same habitat

Gular region: throat or upper foreneck, the area from the lower mandible to the breast bone

Gular sac or pouch:located below lower mandible; allows some species to hold their food; bare skin on throat and base of mandible; in some birds inflates during courtship ritual

Habitat: enviroment in which bird species lives

Half life: time required for the level of substance in body (e.g., drug or toxin) to be reduced by half

Hallux: short hind toe, known as first toe, smaller of the back toes

Hamartoma: benign, tumor-like nodule composed of overgrowth of mature cells and tissues normally present in the affected area but with one element prodominating and growing in a disorganized mass.; benign, focal malformation that resembles a neoplasm; it grows at the same rate as the tissue it is a part of. They occur in many different parts of the body and are most often asymptomatic and undetected unless seen on an image taken for another reason. Disfiguring on skin and damaging to internal structures by compression

• Vascular hamartoma: dermal tumor mass consisting of blood vessels
• Parenchymal hamartoma of the lung. The surrounding lung falls away from the well-circumscribed mass, a typical feature of these lesions. The hamartoma shows a variegated yellow and white appearance which corresponds respectively to cholesterol and fat

Hatching: producing young birds through incubation

Hatch year: HY: age designation of a young bird that is still in its first calendar year of life; no matter when it hatched; on Jan. 2 it becomes a second-year bird (SY); bird in its hatch year is a juvenile; After hatch year (AHY) bird is in at least its second calendar year, but whether it is in its second year or older cannot be determined; after second-year, bird known to be at least in its third calendar year or older

Haversian system: small canals through which blood vessels ramify in bone (Ramify: to divide or spread out into branches or branchilike parts)

Hawking: action of catching insects on the wing

Healing by first intention: union or restoration of continuity occurs directly without intervention of granulations.  Healing by fibrous adhesion, without suppuration or formation of granulation tissue. Also called primary adhesion, primary union.  In primary wound healing there is no tissue loss.

A, Incised wound is held together by a blood clot and possibly by sutures or surgical clamps. An inflammatory process begins in adjacent tissue at the moment of injury.

B, After several days, granulation tissue forms as a result of migration of fibroblasts to the area of injury and formation of new capillaries. Epithelial cells at wound margin migrate to clot and seal the wound. Regenerating epithelium covers the wound.

C, Scarring occurs as granulation tissue matures and injured tissue is replaced with connective tissue.

Healing by second intention occurs when there is tissue loss, as in extensive burns and deep ulcers. The healing process is more prolonged than in healing by primary intention because large amounts of dead tissue must be removed and replaced with viable cells.

A, Open area is more extensive; inflammatory reaction is more widespread and tends to become chronic.

B, Healing may occur under a scab formed of dried exudate or dried plasma proteins and dead cells (eschar).

C, Fibroblasts and capillary buds migrate toward center of wound to form granulation tissue, which becomes a translucent red color as capillary network develops. Granulation tissue is fragile and bleeds easily.

D, As granulation tissue matures, marginal epithelial cells migrate and proliferate over connective tissue base to form a scar. Contraction of skin around scar is the result of movement of epithelial cells toward center of wound in an attempt to close the defect. Surrounding skin moves toward center of wound in an effort to close the wound.

Healing by third intention: a method of closing a grossly contaminated wound in which the wound is left open until contamination has been markedly reduced and inflammation has subsided and then is closed by first intention or sutures. Also called delayed primary closure.

Heart: Has 4 chambers as in humans

Heart block: electrical impulses of the heart are not properly conducted from the atria (chambers receiving blood) to the ventricles (chambers pumping blood)

Helminths: parasitic worm, e.g., fluke, nematode, or tapeworm

Helminthiasis: disease of helminth parasites; treated with antihelminthics

Hemagglutination: to stick together (agglutinate) and form clumps; clumping of red blood cells by antibodies directed against antigens or viruses

Hemagglutination Inhibition test: sensitivity test for measuring antibody responses, esp to PBFD; gives birds PBFD status

Hemangiolipoma: benign tumor composed of fat and blood vessels

Hemangioma: benign tumor composed of newly formed blood vessels clustered together, usually found on skin and spleen, caused by leucosis virus in birds; leukemia-like malignant viral disease found in animals, esp poultry

Hemangiosarcoma/angiosarcom a malignant tumor of blood vessels composed of epithelial cells; characterized by extensive matastasism; bleeds profusely if cut; occurs in spleen, liver, skin, heart, muscle Hematemisis: vomiting blood from upper digestive tract

Hematochezia: bloody droppings Hematocrit/PCV:  Packed Cell Volume: lab test to monitor number of red blood cells

Hematology: science dealing with structure of blood and bloodforming tissues, such as bone marrow; studies blood’s function in sickness and health

Hematoma/subdural hemorrhage: bruise; mass of blood within the tissues or abnormal blood clotting; result of trauma to the blood vessels

Hematopoisis: production of red and white blood cells and platelets; occurs mainly in bone marrow

Hematuria: blood in urine, kidney, a liver disease

Hemi-parasites: category of brood parasites who lay eggs in other birds’ nests

Hemianopea/hemianoptic: blindness in half the visual fields; occurs with lesions of optic tracts

Hemochromatosis/Iron Storage disease: genetic disorder; excess accumulation of iron in body; damages organs, esp liver, spleen, pancreas; caused by chronic anemia

Hemodilution: increase in fluid content of blood; leads to lower concentration of formed elements

Hemoglobin: oxygen-carrying pigment of RBC’s that gives them their red color; conveys oxygen to tissues; protein found in RBC’s transports oxygen in the blood

Hemoglobinemia: excessive hemoglobin in blood plasma

Hemoglobinuria: presence of hemoglobin pigment in urine; blood in urine

Hemogram: systemic report of findings of blood test

Hemolysis: rupture of erythrocytes with the release of hemoglobin; causes hemoglobin to be released into the blood plasma

Hemolytic anemia: caused by destruction of RBC’s in the vascular system; caused by transfusion reaction, staph, antibodies in immune system; all attack RBC’s

Hemoptysis: expectoration of blood/blood-stained sputum from bronchi, larynx, trachea, or lungs