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.