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Author: Gretchen Kaufman, DVM
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OCW Zoological Medicine 2008
Avian Clinical Practice (2008)
G. Kaufman, DVM
Cummings School of Veterinary Medicine at Tufts University

1. Learning Objectives

The avian section of this course is intended to present an overview of avian diseases with an emphasis placed on the select groups of birds most commonly seen in a clinical setting: psittacines, poultry, pigeons, passerines, raptors and waterfowl. Basic aspects of avian clinical practice will be presented first, followed by focused presentations on these select groups of birds. Color coded topics indicate learning objectives that the student should become familiar with. Specific learning objectives are presented at the beginning of each chapter.

2. Review

Please review your 1st Year Comparative Anatomy prior to attending these lectures.

Additional anatomical highlights of specific groups of birds will be presented in each section.

3. Taxonomy

The class of animals "Aves" is an extremely diverse group of unusual creatures, now known to be direct descendants of dinosaurs. It is a common mistake to assume that all birds are the same, e.g. "this trait is common to dogs, cats, elephants, mice, and birds." We must remember that birds is a class equivalent to mammals.

Avian veterinarians must gain an appreciation for this diversity and have a basic understanding of the different groups of birds. This will help the practitioner draw analogies or make assumptions about potential similar characteristics, behaviors, husbandry needs, or even medical treatments.

The Orders of Birds include:


Order Sphenisciformes


Order Struthioniformes


Order Rheiformes


Order Casuariiformes

cassowaries and emus

Order Apterygiformes


Order Tinamiformes


Order Gaviiformes


Order Podicipediformes


Order Procellariformes

albatrosses, shearwaters, petrels

Order Pellicaniformes

pelicans, gannets, frigate birds, cormorants and allies

Order Ciconiiformes

herons, storks, flamingos, and allies

Order Anseriformes

ducks, geese, swans, and allies

Order Falconiformes

turkey vultures, hawks, eagles, falcons, osprey, etc.

Order Galliformes

chicken, partridges, quail, peacocks, turkeys, and allies

Order Gruiformes

cranes, rails, and allies

Order Charadriiformes

gulls, plovers, auks, shorebirds

Order Columbiformes

pigeons, doves, and allies

Order Psittaciformes

parrots, parakeets, macaws, and allies

Order Cuculiformes

cuckoos, roadrunners, and allies

Order Strigiformes


Order Caprimulgiformes

goatsuckers, nightjars, and allies

Order Apodiformes

swifts and hummingbirds

Order Coliiformes


Order Trogoniformes


Order Coraciiformes

kingfishers, bee-eaters, and allies

Order Piciformes

woodpeckers, toucans, and allies

Order Passeriformes

perching birds or passerines: robins, blue jays, crows, finches, sparrows, warblers, etc.

4. Essentials of Avian Clinical Practice

4.1. Who should do it?

Birds are significantly different from mammals, and although a general veterinary education provides a good foundation for working with a broad spectrum of animals, including birds, a veterinarian that sees birds must pursue some specialty training in order to safely and competently provide care for these animals.

General veterinary practice - General small animal practice is commonly confronted with the first line of avian problems. This can range from local wildlife problems (a blue jay flying into a window, a nest of robins knocked out of a tree), local farm issues with backyard poultry or waterfowl (a lame duck in a flock of six, or a chicken with prolapse), to pet birds in the homes of dog and cat clients (a parakeet wellness exam). Ideally, a general small animal practice should be able to triage such cases through:

  • providing responsible answers to clients and the general public regarding wildlife

  • making appropriate referrals to local rehabilitators

  • providing advice to clients prior to obtaining birds

  • providing basic husbandry and nutrition information to bird owning clients

  • performing physical examinations and assessments on a variety of bird species

  • providing some level of emergency care for birds

  • knowing when to refer to an avian specialty practitioner

In many instances this level of capacity exists in many practices through an associate with an interest in birds, a technician with birds of her own and some experience with rehabilitation, and an owner willing to support occasional bird patients by providing appropriate space and time.

Specialty practice - As a veterinarian, or group of veterinarians, gains more experience, a practice may develop the ability to act as a regional referral facility for birds, with regular bird clientele, designated hospital space and special avian equipment, and dedicated trained technical support to care for and provide assistance. In rare instances, some regions of the country can support an all avian, or all exotic practice as a top of the line referral facility, however, many regions of the country cannot. Consequently, avian expertise is often represented as some percentage of a small animal practice (>10%). There are significant continuing education opportunities for avian practitioners to build their competency over time if they chose to do so. Maintaining good relations with regional practices, local breeders, avian distributors and pet stores, are all very important for the development of a successful referral service, regardless of the setting.

Treating wild birds - Wild birds are cared for by local veterinarians, wildlife rehabilitators, occasionally institutions such as zoos or science centers, specialty avian practices and academic centers (such as the Tufts Wildlife Clinic). This work must be done in compliance with State and Federal laws. In addition, a strong and active relationship with the local rehabilitation community is very important. Although the medicine of wild birds is very similar to the medicine of captive birds, the management and criteria for evaluation of such patients is quite different and requires some level of experience and the appropriate facilities. In most instances, wild bird patients should not be kept in the same facilities as domestic animal (including pet bird) patients due to the high level of stress and possibility of disease transmission. Practices that support wild bird rehabilitation will usually have caging facilities in a separate building (such as a garage or barn), or will work very closely with a local rehabilitator that has the appropriate facilities. Such practices must also have ready access to appropriate foodstuffs (e.g. fish, mice, wild bird seed, etc.) to support these patients without delay. Developing a relationship with a regional academic institution (such as the Tufts Wildlife Clinic) will be essential for support and referrals when necessary.

Treating poultry - Many backyard poultry are treated by local veterinary practices, small animal (in suburban settings), ambulatory farm practices, or mixed animal practices (in rural settings). In some states, agricultural extension services may be available for poultry problems. It is rare that poultry specialists are available, except for industrial food production operations. For example, there are only a handful of members of the American College of Poultry Veterinarians in all of New England. They are all associated with academic or consultant practices. Backyard poultry can be treated similarly to wild birds and pet birds. Additional information regarding antibiotic withdrawal times, methods of euthanasia etc. should be taken into account when developing treatment plans for food animals. Some clients will have developed a strong bond with their pet rooster and will expect the same level of care and financial commitment as someone with a beloved amazon parrot.

The key is to know your own limitations, develop relationships with your colleagues and know when to refer or take referrals.

4.1.1. Professional support and resources

Several of the following organizations provide educational, training and support for developing skills in treating birds through conferences, workshops, and publications. Participation and networking through such organizations is highly recommended for successful practice of avian medicine.

Association of Avian Veterinarians (AAV) http://www.aav.org/

Mid-Atlantic States Association of Avian Veterinarians http://www.masaav.org/

American Board of Veterinary Practitioners - Avian Specialty http://www.abvp.com/categories_avian.htm

American College of Poultry Veterinarians http://www.acpv.info/

International Wildlife Rehabilitation Council http://www.iwrc-online.org/

National Wildlife Rehabilitators Association http://www.nwrawildlife.org/home.asp

4.2. Basic practice requirements

4.2.1. Physical setting

A veterinary hospital that sees birds on a regular basis must invest in some basic bird specific equipment and facilities.

Some Basic Equipment for Avian Practice

  • Gram scale (0 to 3 kg, accurate to the gram)

  • Microtip culturettes

  • Microtainers (small blood collection tubes)

  • Fine needles (22, 24, 25, 27, 30 ga.)

  • Small spinal needles (IO catheters)

  • Towels and restraint gloves

  • Disinfectants effective against Chlamydia and Mycobacterium

  • Stocked avian medications

  • Magnification for surgery and examination

  • Appropriate avian surgery and anesthesia equipment (isoflurane, Cole ET tubes)

Facilities should ideally include:

  • a separate waiting room, or protected alcove

  • a secure, low- ceiling exam room

  • a separate avian ward with options for heat

  • appropriate caging that prevents disease transmission and allows effective disinfection.

4.2.2. Staff and technical requirements

Trained technical staff is essential to provide restraint, animal care, grooming services, advice to clients. Training opportunities exist in many veterinary technician programs, as well as at professional meetings and workshops. In addition, reception staff should be aware of avian issues in order to be able to sensitively address clients' needs and answer basic questions. Reception staff should also be given some training in answering wild bird questions from the public, or referring such questions to a local rehabilitator (have names and contact numbers handy).

4.2.3. Resources

An avian practice should invest in and maintain a small library of veterinary materials for consultation. This library should include at a minimum: a parrot identification guide, a wild bird identification guide (e.g. Audubon), a good comprehensive avian medicine text, subscription to the Journal of Avian Medicine and Surgery, and a subscription to Exotic DVM and Veterinary clinics of North America - Exotic Animal Medicine series.


4.2.4. Client relations & education

Avian clients are often not as knowledgeable about their pets as traditional dog and cat clients. Their intuition and understanding of what their pet is doing or needs is often not very good. Consequently they require more understanding and guidance than other clients. A practice that sees birds, should make an effort to provide information to their clients about their pets through direct information and educational handouts. Information sheets can be developed on an individual basis or can be purchased from an outside source (such as the AAV ) for distribution to clients when needed. Technicians and reception staff should be able to provide basic advice when clients ask questions, or should refer these questions to the veterinarian responsible. Some practices provide evening talks for their clients on a regular basis to improve home care and build relationships.

5. Choosing the right bird

Ideally, the veterinarian's involvement begins before the client selects their bird. What is involved in choosing the right bird? There are many variables to consider. Some important questions to raise with the prospective owner are: the purpose of the pet or animal, the personalities of various species, the lifestyle of the person involved, what they are willing to invest, and the experience of the prospective owner with birds. Due to the possible substantial investment of money and time and the longevity of some of these birds (100 years for an Amazon!), examination of these issues can be very important.

There is a significant difference between the human "hand-raised" baby bird and an adult bird caught in the wild, or even a captive born chick that has been raised by its parents. The hand-raised baby is imprinted on humans and produces a better adjusted, amiable, more interactive pet.


The budgie and cockatiel (12 years?) vs. the cockatoo, macaw, or amazon (40-100 yrs.!) represents a substantial commitment beyond what one might expect with a more traditional pet. Some of these birds go on to become part of the family, and are passed down through one or two generations.

6. Transporting birds

When transporting birds, it is important that they are secure, protected from draughts but have adequate ventilation, and do not have toys or bowls that can hurt them when in motion. In cold weather, cages and carriers should be protected from the wind with a towel or blanket and vehicles should be pre-warmed before putting the cage in the car. Small birds being transported to the veterinarian can often be brought in their own small cage. This allows the veterinarian to assess the caging environment and examine the droppings. Larger birds should be transported in a secure pet carrier (a cat carrier will do). It is usually not necessary to provide a perch for short trips. Discourage owners from bringing in birds on their shoulder without any restraint - accidents can easily happen, especially in a waiting room full of excited dogs and cats.

7. First contact: the "new bird" veterinary exam

As with cats and dogs, a veterinary examination is strongly recommended soon after someone acquires a new bird. During this examination the veterinarian establishes a baseline history, initial body weight and physical examination and may perform some laboratory work (baseline CBC/Chemistry, serology, cultures, etc.) as dictated by the specific situation. This first visit provides an opportunity to discuss husbandry, nutrition and behavior, and helps to get the new owner off on the right foot. Sending the client home with appropriate informational handouts, some good food samples, and an appointment for a recheck (annual) is a good start.

8. Routine grooming

Routine grooming procedures such as wing clipping, nail trimming, beak trimming, etc. are performed only as needed by the individual bird and client. Many birds do not need grooming, i.e. their wings are allowed to grow, and they keep their own beaks and nails in shape. However, certain situations dictate that an animal's wings are clipped regularly, usually two or more times yearly. Clipped wings permit greater control over the bird's movements and allow for easier taming. Clipping before the summer season is highly recommended to prevent flying away through an open door or window. Nails require trimming to keep the owner comfortable when handling the bird, and occasionally the beak has abnormal growth or occlusion and requires filing.

Some owners like to come in at least once a year for these procedures along with a physical examination. Others perform the grooming tasks themselves (with the cooperation of the bird!) or take the bird to a pet store for the service.

Wing trim
Wing Trim

Beak trim
Beak trim

9. Avian Behavior

9.1. Wild birds

It is important for anyone working with wild birds to respect the natural behaviors of their patients. In most instances, wild birds in a clinical setting will be extremely stressed. Stress is not always displayed as active fear or through trying to escape. Many species are very stoic and will internalize their stress (and also hide signs of disease). Some animals, particularly owls, may appear semi-comatose. This is called "akenesis". Other birds will frantically try to escape, regardless of their injuries, and still others will appear aggressive. To reduce stress, wild birds should be kept in quiet surroundings, away from human disturbance as much as possible. It is important to adequately understand the normal behavioral habits of a wild bird species in order to provide an appropriate captive environment.

  • Birds that normally perch in brush, should be given brush (or equivalent) to perch in a cage.

  • Small owls, such as screech owls, that hide in the day time in a tree hollow, should be given a small box with a hole in it to allow them to simulate this behavior.

  • Highly social geese, used to interacting with others all day long, should be kept in pairs, or single animals should be given a full length mirror as a source of comfort and stimulation.

  • Giving appropriate space and solitude to a morning dove, prone to bolting upward when frightened and skinning the top of its head.

  • Providing a dummy falcon mother may comfort and assist in feeding young peregrine falcons.

  • Solitary animals should not be housed with others.

  • Animals should be given adequate flight or exercise space, appropriate for their lifestyle and stage of healing.

One may be able to take advantage of natural behaviors for treatment or handling.

  • Turning out the lights to calm or rest an animal

  • Using a hood or covering the head of a raptor to facilitate restraint

  • Floating food or medication in a large water bowl for geese that won't recognize dry food.

  • Feeding owls in the evening, rather than first thing in the morning.

One must also be cognizant of natural behaviors to avoid injury when interacting with birds.

  • Improperly restrained Great horned owl striking with incredible talon strength normally used to attack competitors or grab prey (a skunk is a favorite!)

  • Herons natural tendency to poke at the face with it's sharp pointed beak - face shield is recommended whenever handling

Imprinting in birds is a real and important consideration when dealing with young wild birds. Raptors and waterfowl are known to imprint readily on humans. Imprinting is the process by which these birds define their conspecifics, their parents, their competitors, and their future mates. A bird that imprints on a human may be irreversibly altered and may not be suitable for a life in the wild. It is imperative to avoid imprinting when treating young birds intended for future release. This can be accomplished through minimal contact (reduced visual and auditory contact) use of puppets, and ideally use of a surrogate or foster parent.

9.2. Psittacines

Pet birds require a significant amount of daily attention. They are extremely social creatures in the wild and this need for social interaction is maintained in captive birds. If they are not sufficiently entertained they may develop neurotic behaviors such as screaming at inappropriate times, destructive behavior to people and the environment, and most tragically, self-destructive behavior such as feather picking and self mutilation.

9.2.1. Screaming

Some vocalization must be accepted as normal and natural behavior. In the wild, birds often scream to flock mates when they can't see them, but they know they are around. Screaming is usually for a specific reason (angry, hungry, lights out?, change of routine, calling the "flock", bored) and it may be helpful to try to understand what the bird is asking for. Excessive screaming may be an expression of dominance or for attention getting (it is inappropriate to scream back at the bird). Respecting and sticking to a routine, covering the cage, or banishing may decrease unwanted screaming.

9.2.2. Talking (or not Talking)

Certain species are better talkers than others (Amazons, African Greys), but there are always individual influences. Many African Greys do not talk!

9.2.3. Fearfulness

This is an innate characteristic of many species (cockatiels, A. Greys, conures) and cannot be changed, but should be respected. At other times the environmental conditions may promote fearful behaviors: the bird does not feel like it is in a protective flock.

9.2.4. Aggressiveness

  • Towards people

  • Towards other birds

Biting or other forms of aggressiveness are both innate and learned. Innate forms of aggression involve mate competition, territorial defense, possessiveness (resource guarding), play aggression, and aggression in response to inappropriate confinement. For example, a young African Grey parrot may display aggressive behavior in response to fear. Parrots, as highly intelligent animals, can also easily learn to use aggressive behavior to their advantage with poor training, or inappropriate reinforcement (often unknowingly) by their caretakers. . They may also develop aggressive behavior out of frustration. Individual animals may be more or less aggressive as a matter of their personal nature and without obvious explanation. Aggression toward a particular individual may develop either because of history of abuse by that person or similar person, or due to mating behavior (wanting to guard its mate, offspring and nest).

There are many opinions on how to handle aggressive behavior in parrots. Removing the stimulus, if reasonable and if known, is a good first start. Some suggest to re-adjust the pecking order, keep wings clipped, and do not allow the behavior. A basic approach might include:

  • Recording aggressive behavior in a journal to accurately define

  • Avoid the circumstances that produce the aggression

  • Avoid punishment, reinforcement, or "working through" the aggression

  • Divert the bird's attention

  • Reinforce other behaviors

  • Work on and reward cooperative behavior

  • Develop alternative behaviors incompatible with the aggressive behavior

  • Use repetition of alternative behavior to decrease aggression

9.2.5. Feather picking and Self-mutilation

Feather picking/self-mutilation is a common disorder with multiple possible etiologies. It is often determined to be a behavior disorder (neurosis) and is diagnosed by eliminating other causes. This makes exact diagnosis difficult and expensive. It is frequently a recurring or chronic behavior and may be a stress, boredom or frustration response, most common in "fearful" birds such as cockatoos, African Greys, conures and cockatiels. Active self-mutilation is most common in cockatoos.

Differential diagnosis for the appearance of feather picking and/or self mutilation include: behavioral/environmental causes, contact or allergic dermatopathy, secondary to trauma, bacterial or fungal dermatitis/folliculitis, liver disease, intestinal irritation (parasitic, bacterial enteritis), Polyomavirus, Beak and Feather disease virus, and hypothyroidism or other hormonal imbalance.

Diagnosis can be made through careful examination of the history, the bird's environment, and the condition of the feathers and skin. Blood tests, cultures, fecal analysis, are helpful in ruling out some of the etiologies.

Treatment should be directed toward the cause. Treatment of neurotic feather picking can involve changing the environment, using behavioral training techniques, using a collar to prevent picking (stressful), and using medication (tranquilizers, sedatives, anti-psychotic drugs and hormone therapies) to change behavior. None of the treatments are effective in every case.

11852 (242 x 360)

11941 (240 x 360) Conure

Self-mutilation in a cockatoo and a conure

10. Recognizing a "sick" bird

Most bird patients (except poultry) are still wild birds and will generally try their hardest to hide any symptoms of disease or distress. This is a survival mechanism, to minimize the ability of a predator to recognize a weak or injured prey target. Because this instinct is so well preserved, many birds do not appear "sick" until they are very advanced in their disease. Very observant owners may develop a sense of when their pet is not feeling well, but may not be able to identify specific symptoms. Birds by nature will also generally deteriorate more rapidly than their mammal counterparts, possibly because of their faster metabolic rate. Consequently, the veterinarian must respond quickly and aggressively to sometimes very non-specific signs of a problem.

Non-specific signs of disease may include:

  • anorexia or change in food preference

  • change in voice or lack of vocalization

  • decreased activity, perching in one spot exclusively

  • falling off the perch

  • remaining at the bottom of the cage

  • increased sleepiness

  • exercise intolerance

  • change in behavior - sudden shyness or aggressiveness

  • "fluffed" appearance - difficulty in thermoregulation

  • droopy eyes

More obvious signs of disease may include:

  • postural abnormalities - crouched appearance, favoring one leg, drooping a wing, head tilt, etc.

  • nasal discharge, sneezing, coughing

  • labored breathing (dyspnea)

  • regurgitation/vomiting

  • change in feces, color and consistency

  • straining

  • bloated/distended abdomen

  • overgrown beak, abnormal feathers/molting

11. References and Resources

Main reference texts for avian medicine include:

Veterinary Clinics of North America, Exotic Animal Medicine series. WB Saunders, Co.

BSAVA Manual of Psittacine Birds. John Chitty and Nigel Harcourt-Brown (Eds.) British Small Animal Veterinary Association; 2nd ed., 2005. (This text is used in the Advanced Avian Elective)

Altman, Robert B., et al. Avian Medicine and Surgery. Philadelphia. W.B. Saunders Co., 1997.

Harrison, Gregg J. and Teresa L. Lightfoot. Clinical Avian Medicine. Palm Beach, FL: Spix Pub., c2006. Chapters 1-4.

Olsen, Glenn H., and Susan E. Orosz. Manual of Avian Medicine. Mosby, 2000.

Ritchie, Branson W., et al. Avian Medicine: Principles and Application. Lake Worth, Fla.: Wingers Publishing, c1994.

Tully, Thomas N, Lawton, Martin P.C., and Dorestein, Gerry M. (ed.) Avian Medicine. Boston: Butterworth Heinemann, 2000.

11.1. Behavior Texts and Articles

Garner, Michael M. Techniques and trends in the characterization of inflammatory skin disease in feather picking birds. American Association of Zoological Veterinarians Annual Conference Proceeding , 2006: 19-22.

Heidenriech, Barbara. Good Bird! A Guide to Solving Behavioral Problems in Companion Parrots. Avian Publications, 2004. Available from Amazon.com.

Manual of parrot behavior. Andrew U. Luescher, ed. Ames, IA: Blackwell publishing, 2006.

Meehan, C.L., Millam, J.R., and J.A. Mench. Foraging opportunity and increased physical complexity both prevent and reduce psychogenic feather picking by young Amazon parrots. Applied Animal Behaviour Science,

80 (1), 2003 : 71-85.

Seibert, LM, et al. Placebo-controlled clomipramine trial for the treatment of feather picking disorder in cockatoos. JAAHA, 40, 2004: 261-269.

Smith, Ione L. Basic behavioral principles for the avian veterinarian. Proceedings of the Annual Conference of the Association for Avian Veterinarians, New Orleans, LA, 1999: 47-55.

Welle, Kenneth R. Clinical approach to feather picking. Proceedings of the Annual Conference of the Association for Avian Veterinarians, New Orleans, LA, 1999: 119-124.

Welle, Kenneth. Psittacine behavior handbook. Bedford, TX: Association of Avian Veterinarians, 1999.