Patho-Surveillance and Pathology of Fascioliosis (Fasciola gigantica) in Black Bengal Goats in Bangladesh

Abstract

The aim of the study was conducted to investigate patho-surveillance and pathology of fascioliosis in Black Bengal goats in Sylhet region of Bangladesh. Patho-surveillance and Pathology on fascioliasis of Black Bengal goats were undertaken in such localities under different climatic conditions existing in Sylhet region of five different Upazilla. Goats were divided into young and adult groups. Affected liver samples from slaughtered goats were collected randomly and examined by grossly and histopathological study for hematoxylin and eosin staining. A total of 2000 Black Bengal goat livers were examined, of which 202(10.10%) livers were found to be affected with fascioliosis. Prevalence of fascioliosis was significantly higher in young goats (15.58 %) than in adult (9.59%) and female goats (13.10%) were more susceptible than male goats (7.10%). Seasonal prevalence of fascioliosis was also studied. Highest prevalence (16.51 %) was recorded during rainy season and lowest prevalence (4.70%) was recorded during summer season. Grossly, affected livers were enlarged with rounded edges and thickened capsule. In acute cases, numerous haemorrhagic spots were found on the parietal & visceral surfaces of the affected liver. In chronic form, liver was cirrhotic and reduced in size. The affected intra-hepatic bile ducts were protruded and engorged with flukes. Microscopically, migratory tracts were represented by the presence of haemorrhage, edema and infiltration of numerous eosinophils mixed with few lymphocytes. Fatty change, atrophy and necrosis of hepatocytes were recorded along with deposition of bile pigment in hepatic parenchyma and damage of portal tract area. The wall of bile ducts was thickened due to fibrosis and lining epithelia were hyperplastic. Cross sections of adult and immature flukes were found within the lumen of the thickened bile ducts and hepatic parenchyma respectively. The study to provides valuable in insight towards better understanding of epidemiology and pathogenesis of the disease in Black Bengal goats to adopt suitable control strategies against the disease and meat inspection at slaughter houses.