MORPHOLOGIC AND IMMUNOHISTOCHEMICAL CHARACTERIZATION OF THE HEPATIC-LESIONS ASSOCIATED WITH EUROPEAN BROWN-HARE SYNDROME

Liver lesions were studied in 40 free-living adult European brown hare s (Lepus europaeus) and varying hares (Lepus timidus) of both sexes th at had died in Sweden with the viral infection European brown hare syn drome (EBHS). The lesions were characterized by their histopathologic, immunohistochemical, and electron microscopic findings. Periportal to massive coagulation necrosis was a distinctive feature of EBHS. Lytic necrosis, inflammation, fatty degeneration, and cholangitis occurred variably. Accumulation of basophilic granules in the cytoplasm of hepa tocytes was commonly observed; these lesions corresponded ultrastructu rally to mitochondrial calcification. Viral antigen was revealed in th e cytoplasm and nucleus of hepatocytes and in the cytoplasm of macroph ages.