ABSTRACT
Liver disease can result from congenital abnormalities, trauma, metabolic and nutritional disorders, toxins, parasites, infectious agents (bacterial, fungal, viral, chlamydial, mycobacterial and rickettsial), and neoplasia. Often the exact aetiology cannot be determined, lost in the fibrotic changes accompanying the disease. Trauma can cause tearing of the liver parenchyma and/or the capsule. This occurs when the bird is subjected to massive force (e.g. a moving motor vehicle) or when the liver is friable due to other problems (e.g. hepatic lipidosis). Amyloidosis is most commonly seen in raptors, waterfowl and passerine birds. Amyloid A is a degradation product of inflammatory proteins and its deposition is commonly seen in birds with chronic disease. Haemosiderosis occurs when there is more iron in the circulation than is needed for erythrogenesis, allowing the iron to accumulate in the liver. It results from excess iron intake, either dietary or via excessive blood transfusion.
