Physical Examination of the Avian Patient

Introduction

A tremendous amount of information may be obtained from a good physical examination in the avian patient. However before a finger is ever laid on your patient, valuable diagnostic information can be obtained from a detailed history followed by careful assessment of the patient’s environment or cage. Visual examination of the avian patient can also glean useful information–and more importantly careful observation can also warn you when the patient is not strong enough to handle the stress of manual restraint (Fig 1).

Figure 1. An accurate physical examination in the avian patient should always be preceded by a detailed history and careful visual observation. Click image to enlarge.

History

First address the presenter’s chief complaint or reason(s) for presenting the bird (Fig 2).

• What is the problem?
• What is the progression and/or duration of clinical signs?
• Have any treatments been provided?
• Has there been any response to therapy?

Figure 2. Obtain a detailed history, beginning with the owner or agent’s chief complaint. Photo credit: Dr. Christal Pollock. Click image to enlarge.

Although the history is important in all species, it is especially crucial to obtain a detailed and accurate history in exotic animals. A significant portion of the health problems seen are related to environment or husbandry.

Also verify signalment.

• Does the owner know exactly what species they own? The answer to this question can provide clues to the level of owner experience.
  • Beware. Some individuals may also attempt to misrepresent a species that is illegal in certain states like the monk or quaker parakeet (Myiopsitta monachus).
• Is the bird male or female? Many avian species are sexually monomorphic, however there are examples of sexual dimorphism in the bird world (Box 1):
  

  Box 1. Sexual dimorphism in birds

  Species	Male	Female
  Budgerigar parakeet	Blue cere	Brown or pink-tan cere
  Canary	More melodious song
  Cockatiel (standard or wild-type)	Yellow foreheads, throats, crests and bright orange cheek patches. Solid black plumage under the wingsMore melodious song	Less yellow and barred pattern underneath wings and tail feathers
  Cockatoos, white and pink	Dark brown or black iris	Red-brown or light brown iris
  Eclectus parrot	Green plumage	Red plumage
  Raptors		Larger body size
  Ratites	Intromittent phallus
  Waterfowl	Intromittent phallus

Always verify HOW an owner has determined their bird is male or female, as many owners of sexually monomorphic species rely upon ‘intuition’ to determine gender (Fig 3).

Figure 3. The only fool proof method of gender identification in the sexually monomorphic bird species is observation of egg laying. Click image to enlarge.

Acceptable methods of gender determination include:

• DNA analysis (Fig 3)
• Laparoscopic exam (Fig 4)
• Egg laying (the only fool proof method of gender identification)

Figure 4. The laparoscopic view of the ovary in this mature cockatoo is obvious, however mistakes in gender identification can be made when the bird is ‘scoped’ while young or when the gonads are quiescent. Image provided by Dr. Stephen Divers. Click image to enlarge.

The owner of a hen that has produced eggs should always be questioned further:

• When was the last clutch (or collection of eggs) laid?
• How many eggs are usually laid in a clutch?
• Have any malformed or abnormally shelled eggs been produced?
• Has any broody behavior (e.g. shredding paper, regurgitating to a mirror, seeking dark places) been observed?

Visual examination

A wealth of information may be gleaned from the visual or hand’s off exam. Most importantly, the history and visual exam provides a valuable 5 to 10 minute acclimation period, which gives the bird time to relax. Subtle signs of critical illness that might otherwise be missed can be detected and addressed (Fig 5). Visual examination comes in two stages. First, carefully observe the bird. Then carefully study the bird’s caging

Figure 5. An acclimation period of 5 to 10 minutes can give the patient time to relax and display signs of illness it may have been able to hide briefly. Image provided by Dr. Susan Orosz.

Observe the bird carefully

Observe the bird carefully for non-specific signs of illness (Box 2) or dyspnea (Box 3). Does the visual examination indicate the bird is strong enough to handle a complete physical examination? Or is the bird so ill that only a cursory exam can be performed? Or perhaps the bird is not strong enough to tolerate the stress of any restraint at the moment. For the latter patients, provide supplemental heat and/or supplemental oxygen as needed and place the bird in a dark, quiet environment. Remove all perches and place preferred foods nearby. Begin diagnostic procedures, including physical examination and treatment, in stages in critically ill patients.

Figure 6. The healthy avian patient does NOT sleep or close its eyes in the exam room. Image provided by Dr. Susan Orosz. Click image to enlarge.

Figure 7. It is imperative that signs of increased respiratory effort, like open-mouth breathing, be recognized and addressed before the physical exam begins. Click image to enlarge.

Visit Respiratory Emergencies in the Bird for a brief video clip illustrating increased respiratory effort in the avian patient, and visit the RACE-approved webinar recording “Avian Respiratory Anatomy, Physiology & Disease:  An Overview” for additional information.

Signs of upper respiratory disease can include, but are not limited to oculonasal discharge, periocular swelling, evidence of trauma around the eyes or nose, frequent yawning, and/or change in or absence of voice.

Also evaluate all three components of the bird’s droppings, urine, urates, and feces, during the visual exam. The appearance of the droppings will vary with the species. For instance, budgerigars are from an arid climate and produce small, dry droppings. Frugivores, like lories and lorikeets, have wet, voluminous stools. The fecal component may change color with the diet. For instance, red or blue berries often produce red or blue stool due to the rapid gastrointestinal transit time. Keep in mind that the first few droppings passed by a stressed bird are often polyuric. Persistent polyuria can be seen with endocrine disease or renal disease. Biliverdinuria, or the green or yellow-green tinge of urates, can be seen with some forms of liver dysfunction.

There are many other potential observations during the hands-off exam that can provide clues to your patient’s health status, including feather quality (Fig 10), conformation, posture, wing droop, and wing posture (Fig 8-Fig 10). A wing droop can be observed with musculoskeletal or neurologic lesions of the wing or pectoral girdle. The normal bird extends both wings out symmetrically for balance (Fig 8). Failure to do so can indicate a lesion of the assymetrical wing. In conditions causing paresis or paralysis of the pelvic limb, such as renal or gonadal tumors, the bird will often rest the plantar surface of the tarsometatarsus on the perch or cage floor. Orthopedic conditions causing lameness frequently result in the bird holding up the foot.

Visit Body Condition Scoring in Birds for helpful clues during the visual exam.

Figure 8. Birds normally extend both wings out symmetrically for balance, however note this falcon does lack a strong grip. Physical examination confirmed the presence of neurologic deficits. Image by Dr. Ed Ramsay. Click image to enlarge.

Figure 9. Fat deposits along either side of the keel can cause feathers to part over the sternum (arrow). The presence of “cleavage” does not necessarily mean the bird is overweight and palpation is required. Image provided by Dr. Gwen Flinchum. Click image to enlarge.

Figure 10. This orange-wing Amazon parrot (Amazona amazonica) should have brilliant green plumage. Although this patient may present acutely, only chronic disease and/or malnutrition could cause such dark, abnormal plumage. Image by Dr. Susan Orosz. Click image to enlarge.

Examine and/or discuss the bird’s environment

Whenever possible, the owner should be instructed to present the pet bird in its own cage and not to clean the cage for 12-24 hours prior to the visit (Fig 11). A number of features of the cage should be evaluated:

• What type of metal is the cage made from?
• What are the cage dimensions?
• Where are perches and food bowls located?
• What cage furniture is present?
• What substrate is used?
• Cage hygiene practices should also be discussed.
• How often is the cage cleaned?
• What disinfectant is used and how often?
• Diet:
  What food is offered to the bird, and what items are actually consumed and in what proportions?
• Is vitamin/mineral supplementation or grit provided?
• What is the source of drinking water?

Figure 11. Carefully evaluate the bird’s environment for helpful clues. Image by Dr. Carol Gamble. Click image to enlarge.

Before picking up the bird…

Before picking up the bird, carefully consider is my patient strong enough to handle the stress of manual restraint and physical examination? (See visual examination above). Also consider the equipment needed and restraint.

What equipment will I need?

Before catching up the bird be prepared. Gather all equipment that might be needed, and make sure the room is secure. Equipment required will vary, but should always include a Gram scale sensitive to 1-to-2 gram weight increments, a towel or paper towel for restraint, a bright light source, and an oral speculum (Fig 12). Additional supplies that may be needed include a magnifying loupe, ear protection equipment, and grooming equipment.

Figure 12. Equipment needed for the avian exam varies, but typically includes a gram scale, bright light source, and oral speculum. Image by Dr. Christal Pollock. Click image to enlarge.

Restraint

Tame birds do not allow thorough physical examination unrestrained. The rare exception to this rule is the pediatric patient and some cockatoos (Fig 13). These individuals should be touched and palpated as though the exam was a petting session, saving any potentially stressful procedures, such as oral and cloacal exam, to the end.

Figure 13. While one person (left) pets and talks to the chick; a second person can perform much of the physical exam. Image by Dr. Susan Orosz. Click image to enlarge.

Never attempt to restrain a bird that appears very weak or dyspneic since these patients can and will die from the stress of restraint. Never catch up a bird from an owner’s shoulder.

When catching up a parrot, the first goal is to restrain the head. Once the bird is in your grasp, the sternum must always be left unrestrained since sternal motion is essential for normal respirations. When catching up a bird of prey, the first goal is to restrain the feet (Fig 14).

Visit Parrot Handling & Restraint and Passerine Handling & Restraint for instructional video clips or text with still images. Visit Restraint of Wild Birds for guidance on handling of raptors of other free-ranging species.

Figure 14. Even the feet of a small bird of prey like the saw-whet owl (Aegolius acadicus) can inflict significant damage and should be approached with respect. Image by Dr. Christal Pollock. Click image to enlarge.

Physical examination

Follow a similar protocol during each physical examination, and take every opportunity to become familiar with the normal bird.

• Body weight: Obtain a weight at the beginning or end of the exam.
• Symmetry: Carefully study the patient’s head straight on to look for any sign of asymmetry of the beak, eyes, nares, and infraorbital sinus space (Fig 15).

Figure 15. Take a moment to evaluate your patient for any evidence of assymetry. Photo credit: BotheredByBees. Click image to enlarge.

• Eyes:
  
  • Assess the cornea and anterior chamber (Fig 16).
  • Evaluate the pupillary light response:  The avian iris contains variable amounts of skeletal muscle, therefore birds can voluntarily control pupil size.
  • Assess the periorbital and infraorbital regions for any subtle swelling.
  • Fundic examination should always be performed in birds with head trauma, particularly birds of prey.
    

    Figure 16. As in all species, evaluation of the avian eye is an important of the physical exam. Image by Dr. Christal Pollock. Click image to enlarge.

• Ears (Fig 17 and Fig 18)
  • Otitis is relatively uncommon in the bird, but always be sure to evaluate the ear for redness, discharge, and swelling–particularly pediatric patients.
  • Blood or bruising in the ears can be observed in cases of head trauma.
  • Some parasites may also have parasites like ticks within the ear canal.
    

    Figure 17. The appearance of the avian ear varies with the species. Shown here, the ear of a Nanday conure (Nandayus nenday). Image by Dr. Christal Pollock. Click image to enlarge.

    

    Figure 18. Ear of a barred owl (Strix varia) (top); close-up of the ear (bottom). Image by Dr. Christal Pollock. Click images to enlarge.

• Nares
  • Note the operculum and the keratinized plate located just inside the nostril. Is this region clean and clear, or is nasal discharge present?
  • Clumping of the small, spiky feathers behind the nares may be the only sign of nasal discharge or regurgitation in birds still fastidious enough to groom. (This feather clumping is most commonly seen in the budgerigar parakeet). Brown hypertrophy of the cere is a common physical exam finding in older, female budgerigar parakeets (Fig 19). This occurs secondary to the high estrogen levels associated with the production of many clutches. Cere hypertrophy may also occur secondary to pathologic conditions that cause hyperestrogenism like gonadal tumors.

• Beak: The normal beak is smooth. Although a small degree of flakiness is not uncommon in captive birds, the beak should not be excessively flaky, overgrown, or with longitudinal grooves (Fig 20).
  

  Figure 20. The normal beak is smooth. Although a small degree of flakiness is not uncommon in captive birds, the beak should not be excessively flaky, overgrown, or with longitudinal grooves. Image by Drew Avery. Click image to enlarge.

• Oropharynx (Box 4): Although the hands can be used in many avian species, an oral speculum is required to perform an oropharyngeal exam in parrots (Fig 21 and Fig 22). Detailed examination of the oropharynx may require general anesthesia.
  

  Figure 21. The oropharynx may be opened and restrained with the hands in many species of bird. Image provided by Dr. Gretchen Cole. Click image to enlarge.

  

  Figure 22. Upper left: Brief, cursory evaluation of the oropharynx can be performed by bringing a bright light source close to the beak—the healthy parrot will invariably try to bite it. Upper right: Use of a metal oral speculum. Lower left: Padded hemostats can also serve as an oral speculum. Lower right: Alternatively gauze loops can be used to open the mouth. Click image to enlarge.

  Box 4. Performing an oropharyngeal exam in the bird

  Note jaw and tongue tone when opening the mouth. Tongue (Fig 23) Underneath the tongue Glottis Floor of the oropharynx Mucous membrane color Choanal slit Choanal papillae Prominent mucus strands within the oropharynx may be observed in the dehydrated bird

  The appearance of the choanal papillae is extremely variable. For instance, papillae are well-formed and distinct in some species like the Amazon parrot. Birds with head trauma frequently exhibit bleeding from the choanal slit.

  

  Figure 23. Among class Aves, only parrots possess intrinsic tongue muscles. The thick, fleshy parrot tongue makes it relatively difficult to visualize the back of the throat or the region beneath the tongue. Click image to enlarge.

   

  Aquatic birds such as great blue herons (Ardea herodialis) and pelicans (Pelecanus spp.) may normally have 20 to 30 flukes found in the oropharynx.

• Top of the head (Fig 24):  Palpate the top of the head, and visualize the skin and feathers. In birds that have suffered head trauma, it is difficult to palpate an actual skull fracture; however the emphysema created when air escapes pneumatic diverticula can be appreciated.
  

  Figure 24. Lift the crest and part the feathers on the back of the neck to evaluate the skin underneath. Click image to enlarge.

•  Palpate the submandibular area and neck. Since there is no glandular tissue present in the avian neck, a hand is simply run along the neck to evaluate the trachea and esophagus. Transillumination of the trachea can also be performed in tiny patients by using a bright light source in a dark room.

• Move to the thoracic inlet (Fig 25):
  • Gently palpate the crop for the presence of food, fluid, and/or air.
  • Palpate the clavicle and coracoid bones of the pectoral girdle. Like skull fractures, fractures of these bones can be difficult to recognize, but can be associated with subcutaneous emphysema due to rupture of pneumatic diverticula.
    

    Figure 25. Palpate the thoracic inlet to evaluate the crop as well as the clavicle and coracoid. Click image to enlarge.

• Sternum
  • The sternum should be straight. Deviations may be seen with metabolic bone disease or trauma.
  • Palpate the keel or carina and the pectoral muscle mass. As a general rule, the bird in good body condition has rounded or convex, firm pectoral muscles with little subcutaneous fat. Visit Body Condition Scoring in Birds for valuable tips. There are species variations. Some cockatoos, like the lesser sulfur-crested (Cacatua sulphurea) are relatively lean, while many Amazon parrots, like the double yellow-headed Amazon parrot (Amazona ochrocephala ochrocephala) are much stockier. The bird’s activity level directly affects pectoral muscle mass. Flighted birds are more muscular than those with clipped wings. Pediatric and geriatric patients also have relatively flabby, soft, small pectorals.
  • Auscult the heart over the sternal plate. Arrhythmias or murmurs can occasionally be detected despite the bird’s rapid heart rate.

• Coelom:  Coelomic palpation is a relatively insensitive test in the bird due to the short distance between the sternum and pubis. Nevertheless eggs, mass lesions, coelomic fluid, and/or organomegaly may sometimes be detected by gently placing a thumb and forefinger on either side of the coelom. To palpate the coelom, slide a finger along the distal sternum and directly into the coelom (Fig 26). In small birds, the feathers overlying the coelom can be wet down to visually confirm the presence of hepatomegaly through the thin skin.
  

  Figure 26. Coelomic palpation of a parrot. Click image to enlarge.

• Check the vent or the external opening to the cloaca.
  • Does the bird appear to have normal sphincter tone?
  • Is there soiling or feather loss around the vent?

• Plumage: Note feather quality and color (Box 5).

If the species evaluated is a heavy powder down producer such as an African grey parrot (Psittacus erithacus), cockatiel (Nymphicus hollandicus), cockatoo, and pigeon (Columba livia) the examiner’s hands should be dusted with talc-like powder towards the end of the exam (Fig 24). One of the earliest clinical features of psittacine beak and feather disease is a lack of normal powder down production.

Figure 27. The feahers and beak of heavy powder down producers, like this cockatoo, should be chalky.

Figure 28. A clue to the past, stress bars (arrow) are lines of abnormal feather growth that develop secondary to exogenous steroid administration or endogenous cortisol release. Click image to enlarge.

• Pelvic limbs
  • Run your hands along the legs. Briefly evaluate each joint’s range of motion and note the degree of strength in the bird’s grip.
  • The feet should possess prominent scale patterns on both the dorsal and plantar surfaces (Fig 29). In pododermatitis or bumblefoot, the papillae on the bottom of the feet are worn away, leading to redness and ulcerative lesions (Fig 30).
  • Note the toenails. Markedly overgrown nails can be associated with liver dysfunction
    

    Figure 29. The bottoms of the feet should have distinct papillae. Click image to enlarge.

    

    Figure 30. In pododermatitis or ‘bumblefoot’ the papillae on the bottom of the feet are worn away, leading to redness and ulcers. Click image to enlarge.

• Thoracic limbs
  • Palpate the bones and joints of the wings (Fig 31).
  • Evaluate the wing web or patagium as well as the propatagialis tendon in the leading margin of the wing (Fig 32).
  • Palpation should also include the axillae and along the sides of the birds.
  • Vascular perfusion and hydration status can be crudely assessed by compressing the basilic vein (Fig 33).
    

    Figure 31. To safely extend the wing support the wing at the level of the carpus. Click image to enlarge.

    

    Figure 32. During palpation, bring the wing through a passive range of motion. Note the wing is again supported at the level of the carpus (arrow). Click image to enlarge.

    

    Figure 33. Note the turgor of the basilic vessel (arrow) while evaluating the wing. Image provided by Dr. Lauren Powers. Click image to enlarge.

• Dorsum:  Palpate the scapulae. Look and feel over the back for lumps and bumps (Fig 34).
  

  Figure 34. Quickly look and feel over the back. Click image to enlarge.

• Evaluate the uropygial or preen gland at the base of the tail feathers. Absent in the Amazon parrot, the appearance of the uropygial gland varies with the species, but should always be smooth, symmetrical, and even-colored (Fig 35-37). A small amount of yellow or clear fluid may be expressed from the gland, but this material should never be foul smelling.
  

  Figure 35. The preen gland of the screech owl (Otus asio) is among the most prominent. Click image to enlarge.

  

  Figure 36. Close-up of the screech owl (Otus asio) preen gland. Click image to enlarge.

  

  Figure 37. The preen gland in the parrot (arrow) is much smaller with a prominent tuft of feathers at the tip. Click image to enlarge.

• Auscultation of the lungs is performed over the back because the lungs are adhered so dorsally (Fig 38). Because the avian lungs move only minimally, breath sounds usually cannot be heard unless the patient is extremely stressed or severe pulmonary disease is present.
  

  Figure 38. The lungs are tightly adhered dorsally and are best ausculted over the back, however auscultation of the lungs is an insensitive test in the bird. Click image to enlarge.

• Vocalizations:  Most normal parrots vocalize during physical examination. Some species, particularly Pionus parrots can pant when stressed. Note any abnormalities or changes in voice.

• Bruising:  It takes 2 to 3 days for bird bruises to turn their classic green color as hemoglobin breaks down to biliverdin.

Visit Physical Examination of the Chick for information on evaluation of this important demographic.

After the exam

After the examination the “respiratory recovery rate” can serve as a crude indicator of the bird’s general health (Box 6).

Box 6. Respiratory recovery rate