Common Conditions of Pet Birds

General Information

Pet birds often become ill when they are not cared for or fed appropriately. While most avian diseases can affect every species, some species are more prone to develop certain conditions. By being familiar with various conditions that commonly affect a certain species, your veterinarian is able to formulate a diagnostic and treatment protocol resulting in a correct diagnosis and cure for your bird's illness. While it is impossible to list every possible disease that may afflict your bird, the following discussion will familiarize you with some common health conditions your pet bird may encounter. If the signs of these health conditions are noticed, contact your veterinarian right away.


Budgerigars (Budgies)

  • Budgerigars, or budgies, commonly develop cancerous tumors in their kidneys and reproductive organs. Kidney, ovarian, and testicular tumors often cause a unilateral (one-sided) lameness that owners often mistake for an injured leg.
  • Goiter (underactive thyroid gland, or hypothyroidism) also can occur in budgies, especially when they are on all-seed diets. Seed contains very low levels of iodine that is required by the thyroid gland to function properly; therefore, the gland swells to try to extract all the iron it can from the seeds. Budgies afflicted with this condition are often overweight and have a squeaky voice or regurgitate when they eat as a result of the enlarged thyroid gland pressing on the esophagus.
  • Another condition commonly seen in budgies, especially when they are in close contact with other budgies in pet stores, is psittacosis (also called chlamydiosis or parrot fever). It may be carried by budgies without them showing any clinical signs, or infected birds may show respiratory signs (sneezing, difficulty breathing, decreased ability to fly, and tail bobbing) or a swollen abdomen from liver enlargement.  
  • Since many owners incorrectly feed all-seed, high-fat diets to their budgies, obesity is common in these birds. Hepatic lipidosis (fatty liver disease) is a problem that often results and causes death. This species also is predisposed to poor diet-related (high-fat, all-seed) tumors called lipomas and xanthomas that may be found on the wings and ventral abdomen. Lipomas appear as pockets of soft, white, moveable fat, while xanthomas are typically firm, fixed, and yellow-orange.
  • Reproductive problems are very common in pet birds, as well. Egg binding is seen often in pet budgerigars, even those housed individually without a mate, that are still capable of laying eggs. Birds often become egg bound when they are eating diets high in seed that lack calcium and vitamin D, which are critical in the formation and laying of eggs.



  • Cockatiels, like budgies, are commonly afflicted with respiratory disease caused by the bacteria, Chlamydophila psittaci. Like budgies, cockatiels can carry this organism without any signs, shedding it in their stool and respiratory tract secretions to other birds, or they may develop respiratory signs, weakness, and enlarged livers.
  • Another organism that commonly affects cockatiels is the internal parasite, Giardia. Birds infected with Giardia may have diarrhea and be very itchy, violently attacking themselves, especially under the wings.
  • Another disease more commonly seen in cockatiels is gastrointestinal yeast infection with Candida organisms. Birds with yeast often regurgitate, lose weight, and have diarrhea and decreased appetite.
  • Birds on all-seed diets often become obese and develop fatty liver disease (hepatic lipidosis) which can lead to death.
  • Reproductive problems are even more common in cockatiels than in budgies, even in individually housed pets, and include egg binding, soft-shelled to shell-less eggs, oviduct prolapse, and reproductive tumors.



  • Canaries have several genetic-based conditions. Feather cysts, which require surgical removal, frequently occur in canaries.
  • Cataracts also are not uncommon.
  • In addition, baldness of the head of certain male canaries also occurs.
  • An unusual form of knemidokoptic mange called tassel-foot occurs frequently in these popular birds in which mites cause excessive build-up of crust on the skin over the feet, making the feet look like there are tassels hanging off of them.
  • Air sac mites that infect the trachea (windpipe) and air sacs commonly contribute to respiratory disease in canaries. Affected canaries breathe quickly, often with open mouths.
  • In addition, owners who provide their canaries with nesting material made of fine thread often unknowingly cause a problem for their birds. The fine thread can wrap around a toe or foot, impairing the blood circulation and ultimately causing necrosis (death) of the affected toe or foot. With extreme tissue damage, the toe or foot may need to be amputated.
  • Poxvirus causes crusty lesions on the unfeathered skin in canaries and may affect the respiratory system, ultimately causing death.
  • As with other small birds, reproductive problems, such as egg binding, are seen in canaries.



  • Similar to canaries, finches often have air sac mites, leading to severe respiratory disease.
  • In addition, as in canaries, fine thread used as nesting material can wrap around the toes and legs of finches, impairing circulation to the limbs and ultimately requiring amputation of affected tissue.
  • When stressed from overcrowding, finches will often pick feathers off each other, especially around their heads and faces.
  • Finally, these small birds, especially if they are fed all-seed diets deficient in calcium and vitamin D essential for egg production and laying, will often develop egg binding, which can rapidly result in death if not treated early.



  • A strange bleeding syndrome of unknown cause has been reported to occur in conures. When they are injured or when they have blood drawn, they bleed excessively. Luckily this syndrome can be treated effectively if caught early.
  • Feather-picking is seen with some frequency in pet conures when they are stressed or overcrowded.  
  • Nanday and Patagonian conures may carry a herpes virus without showing any clinical signs. This herpes virus causes an illness called Pacheco’s disease in other bird species, particularly Amazon parrots and cockatoos. In these species, Pacheco’s disease typically causes sudden death; therefore, conures should not be housed with other bird species.



  • Like other smaller bird species, lovebirds may be affected with chlamydiosis that typically causes respiratory signs, weakness, liver problems, and death.
  • Lovebirds also commonly develop gastrointestinal tract yeast infections (candidiasis) caused from the yeast Candida.
  • Various infectious causes of feather loss occur in lovebirds, including skin infection with yeast and bacteria, particularly inside the wings.
  • Epilepsy is occasionally seen in lovebirds.
  • Reproductive problems, such as egg binding, seen frequently in other small birds, also occur with some frequency in lovebirds.


African Gray Parrots

  • These extremely intelligent, often high-strung birds frequently develop psychologically-based causes of feather-picking as a result of boredom or loneliness. They will also feather-pick as a result of sexual frustration from not breeding.
  • A potentially fatal syndrome occurs in African grays on all-seed diets in which they develop low blood calcium levels resulting in seizures.
  • Aspergillosis, a potentially fatal fungal infection, is often seen in African grays. The signs include difficulty breathing, sneezing, lethargy, weakness, and weight loss.
  • Bacterial infections of the respiratory tract may cause similar signs as aspergillosis.
  • Cancer is seen with some frequency in this species, as they are a long-lived.
  • Although uncommon these days, beak and feather disease virus may occur in young African grays and is quickly fatal as a result of suppression of the bone marrow.


Amazon Parrots

  • Amazons are commonly afflicted with upper respiratory diseases, many of which result from vitamin A deficiency associated with an all-seed diet.
  • Cloacal papillomas (warts) commonly affect older Amazon parrots and may also appear in their mouths.
  • Amazons may feather-pick, especially their wings and legs, as a result of psychological stress and sexual frustration.
  • Amazons commonly exhibit mating season aggression towards their owners; some of these birds become too aggressive to handle and are given away to shelters.
  • A syndrome of unknown cause, called Amazon foot necrosis syndrome, occurs in Amazon parrots. With this syndrome, parrots violently mutilate the skin on their legs and feet, causing excess bleeding and tissue damage.
  • Some Amazon parrots develop epilepsy.
  • Like African gray parrots, Amazon parrots are long-lived and as a result develop cancer in various organs.
  • Moreover, like most birds on high-fat, all-seed diets, Amazons commonly develop obesity, hepatic lipidosis (fatty liver disease), atherosclerosis (cholesterol deposits in arteries), stroke, and heart disease. 



  • Macaws were the first species to develop an ultimately fatal disease, proventricular dilatation syndrome, which causes chronic and progressive weight loss, regurgitation, and in some birds, ultimately death. This syndrome is believed to be an autoimmune disease associated with a viral infection called bornavirus.  No one yet understands the complete cause of disease, as many bird species are infected with bornavirus and are not clinically affected.
  • Chlamydiosis (infection with the bacteria, Chlamydia psittaci) also occurs in macaws, causing respiratory signs and liver disease.
  • Oral and cloacal papillomatosis (warts) also occurs more frequently in older macaws.
  • Psychologically-based feather-picking often occurs in the larger species of birds that are tightly bonded to their owners; macaws are no exception. They become frustrated because they are bonded to, but not mating with, their human flock-mates.
  • Regression to juvenile behavior may be a sign of illness in sick macaws, especially those with gastrointestinal diseases.



  • Cockatoos, like other large birds, often develop psychologically-based feather-picking that is difficult to treat, particularly because they are so socially needy and require a great deal of attention from their owners. However, other problems, such as infection of skin with bacteria and yeast, may also cause feather loss. For this reason, any feather loss should be thoroughly investigated by your veterinarian.  
  • Like macaws, regression to juvenile behavior is often seen in cockatoos and may be a very early sign of severe illness in this species.
  • Cloacal prolapse, seen most often in sexually mature males, occurs frequently in cockatoos.
  • Lipomas (benign fatty tumors) are commonly seen in rose-breasted cockatoos who have a tendency to become obese.

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