Natural trematode infection in liver of water buffalo (Bubalus bubalis): histopathological investigation

This study reports the infection of liver and bile ducts, carried out from November 2008 to April 2010, on 730 randomly selected water buffaloes—Bubalus bubalis, infected with the amphistome trematode parasite Explanatum explanatum (Creplin, 1847) Fukui, 1929. Macroscopic examination revealed massive infection of adult fluke in bile ducts and intrahepatic ductules in 131 (18%) cases. The predominant features were multifocal granulomatous nodules throughout the luminal surface of the bile ducts. Histopathological study of 4 μm thick tissue sections cut adjacent to and through the site of attachment of individual worm and stained with hematoxylin and eosin revealed intense infiltration of inflammatory cells such as lymphocytes, macrophages, plasma cells, eosinophils as well as fibrocytes. This was associated with fibrosis and thickening of the bile ducts. Due to high level of prevalence and intensity of natural infection, amphistomiasis appears to be endemic in this geographical region and probably represent one of the most important animal health problems. It is hoped that the study may draw attention to the need for educating farmers, regarding the economic importance of infection of these amphistome parasites and also for the development of control strategies to prevent the spread of infection to ruminants.