Inclusion body disease in a peregrine falcon (Falco peregrinus): histological and ultrastructural study.

Histopathological and ultrastructural studies of inclusion body disease of falcons showed severe multifocal hepatic necrosis and haemorrhagic necrotic enteritis. Intranuclear eosinophilic and basophilic inclusion bodies were observed in numerous hepatocytes, intestinal and renal tubular epithelial cells and in mononuclear cells. Transmission electron microscopy revealed herpes virus-like particles in intranuclear inclusion bodies in these cells. The replication of the virus in the liver and the epithelial cells of the intestine and kidney suggest that faeces and urine could transmit the virus, thus being responsible for the spread of the disease.