Margaret A. Wissman, DVM
Malnutrition: Birds consuming a seed-only diet, picky birds and those under stress (such as an egg-laying hen) may suffer from nutritional imbalances such as low calcium or vitamin-A deficiency.
Vitamin-A deficiency: Birds suffering from hypovitaminosis A may have blunted choanal papillae, secondary infections with Candida sp., usually Candida albicans, or other problems.
Feather picking: There are many causes for feather-destructive behavior. Poor wing-feather trimming can cause skin irritation and chewing of the cut tips of primary wing feathers. Intestinal protozoa can cause feather picking. Nutritional problems may also result in feather abnormalities. Endocrine, metabolic, infectious, parasitic, environmental and behavioral problems may also result in feather destructive behavior.
Bacterial infections: While birds are exposed to millions of bacterial organisms every day, most are innocuous or even beneficial. But some bacterial organisms can cause illness in birds, even death.
Psittacosis: This disease is caused by a primitive bacterial organism, almost always Chlamydophila psittaci.
Reproductive problems: Some hens will lay eggs until nutritionally exhausted. An egg may not be expelled normally, resulting in a medical emergency. Other problems can occur if a yolk does not go into the reproductive tract and ends up loose in the coelom. Rarely this may result in yolk-stroke. Regurgitation in many budgies is sexually driven. Males (and occasionally females) may masturbate on toys or a person.
Want to know more about bird illness and what signs to look for? Check out these tips here:
Signs of Sick Birds & What To
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