Natural infection with schistosomes of the Schistosoma haematobium group in a dog in Zambia.

Abstract Post-mortem examination of an adult male Jack Russell dog from Zambia revealed that it was heavily infected with schistosomes. The dog had been admitted, with a history of retching, 4 days before its death. At necropsy, the liver was found to be enlarged, with multiple pin-point yellowish-white foci scattered diffusely throughout the organ. Multiple pin-point recent and old haemorrhages were seen on the mucosal surface of the gastrointestinal tract, particularly in the stomach and proximal duodenum. Large numbers of schistosome worm pairs and eggs were found in all mesenteric, gastric and hepatic veins. Histological examination of the intestines, mesenteric lymph nodes, liver, spleen, pancreas, stomach and lungs revealed numerous strongly fibrotic, encapsulated, epithelioid-giant cell granulomata containing dead, degenerating and viable eggs. A few examples of the Splendore-Hoeppli phenomenon were also detected. The eggs collected at necropsy had a terminal spine and an average length and breadth of 187·6±14·1 μm and 57·3±4·1 μm, respectively. DNA analysis of female worms indicated that the schistosomes were either Schistosoma haematobium or a hybrid of Schistosoma mattheei and S. haematobium .