Comparative pathological study of liver fluke infection in ruminants

A comparative study was conducted from October 2013 to June 2014 on 135 cattle, 175 sheep and 190 goats with a total of 500 ruminants to assess pathological changes on liver infected with fluke at ELFORA export abattoir in Bishoftu, Ethiopia. The animals were included in the study using systematic random sampling. The gross lesions included firm and enlarged livers with tense capsule, haemorrhagic spots, multi focal nodules and enlarged hepatic lymph nodes. The bile ducts were thickened and distended with adult fluke especially in chronic cases. Frequently observed histologic lesions were, hepatic portal fibrosis with large amount of fibrin in the portal area, hepatocytes degeneration, fatty changes and periportal necrosis. Fibrous connective tissue of various amount with fibroblasts and infiltration of mononuclear cells, in particular lymphocytes were common lesions in tracts migrated by parasites. Biliary cirrhosis with epithelial hyperplasia were also observed in cattle and sheep. Eosinophilic hepatitis, talengechtasis and hepatocytes degeneration and necrosis were evident in the parenchyma. Chronic lesions were less prominent in goats’ and even no cirrhotic case examined in goat. Cytological examination showed large number of lymphocytes and few plasma cells and eosinophils. The findings of the present study indicated that gross, histopathological and cytological examination supports one another in characterization of liver lesions hence could be used together in diagnosis of ruminant fasciolosis. However, additional diagnostic tests would be added for better confirmation.