Pathology of natural infections of Schistosoma spindale Montgomery, 1906, in cattle.

The pathology of natural Schistosoma spindale infections in cattle in Sri Lanka was studied. Hepatic lesions were moderate with periportal cell infiltration and periportal epithelioid cell granulomas within perilobular zones. Submucosal and mucosal granulomas accompanied by cellular changes were present in the small and large intestine. Two unusual observations included the migration of an adult worm from the mesenteric veins to the mucosa of the small intestine in one bull and the presence of epithelioid cell granulomas containing slender living eggs in the urinary bladder of one animal. Intensities of infections, histopathological changes and immunological responses are discussed and comparison is made with other schistosome species.