Progressive light microscopic changes in chronic recurrent outbreaks of hepatic coccidiosis in domestic rabbits

Hepatic coccidiosis is an important economic disease of rabbits. The progressive histopathological changes in liver of rabbits infected with Eimeria stiedae in chronic recurrent outbreaks of coccidiosis in organized rabbitries are discussed. One hundred and fifty morbid specimens of rabbit liversamples from known cases of hepatic coccidiosis preserved in 10% formalin were studied. The hepatic parenchyma revealed multifocal areas of coagulative to liquefactive necrosis, congestion, haemorrhages and vacuolar degenerative changes in hepatocytes along with periportal infiltration of numerous lymphocytes and a few neutrophils. Biliary ducts were hyperplastic with pappilomatous ingrowths of epithelium into lumen. In chronic infections, multifocal areas of severe periportal cirrhosis with islands of hepatic parenchyma were seen along with extensive infiltration of lymphocytes, plasma cells and macrophages and prominent calcification of bile ducts. Gall bladder epithelium also showed early lesions of hyperplasia of epithelial cells in mucosa with necrosis and severe inflammation and extensive fibrosis. The intensive growing conditions and contributory factors like high humidity, moisture, feeding and manure disposal system may lead to recurrent outbreaks of hepatic coccidiosis in rabbits.