Risk Factors and Gross Pathology of Bovine Liver Fluke Infection at Netrokona District, Bangladesh

The investigation was aimed to identify the risk factors and gross pathology of liver fluke infection in cattle in Netrokona district of Bangladesh during November 2008 to October 2009. Faecal samples from 350 cattle were examined microscopically using Modified Stoll’s ova counting method, 109 (31.14%) were found positive for Fasciola gigantica and mean eggs per gram of faeces (EPG) were 133.03±9.04. Association of liver fluke infection with age, sex, nutritional condition of the cattle; existence of intermediate host, vegetation with infective metacercariae and seasonal trend were also observed through questionnaire survey. Higher rate of infection was found in older animals compared to younger one. The prevalence of Fascioliasis was higher in females (41.36%) than males (13.85%). Significantly (P<0.05) higher prevalence were found in poor health animals than apparently normal healthy animals. Significantly (P<0.01) higher prevalence of Fascioliasis was recorded in winter season (51.33%) followed by rainy (24.24%) and summer season (18.10%). A total of 278 aquatic snails were collected from the study area, among them 7 (2.52%) were infected with Gymnocephalous cercariae. At necropsy, Fasciola infected liver appeared larger with tensed capsule and bile ducts were dilated, thickened with fibrous tissue masses forming the characteristic pipe-stem liver.