Visceral larva migrans in mice experimentally infected with Baylisascaris transfuga (ascaridae Nematoda)

Laboratory bred albino mice, weighing 20 to 25g, were orally infected with 2000 Baylisascaris trnasfuga infective eggs each. Mice were randomly chosen and sacrificed on days 1, 2, 3, 10, 15, 24 and 70 post-infection. Samples of intestine, mesenteric lymph nodes, liver, lungs, hearts, spleen, kidneys, uterus, brain and skeletal muscles were collected and processed for convetional histopathology. In the early infectionthe major necropsy findings were focal haemorrhages on the intestinal wall, liver lungs and brain. Histologically, larvae were found in haemorrhagic areas. In the subacute-Chronic infection white nodules were scattered through all the examined organs, except the brain. Histologically, the white nodules corrisponded to granulomas containing larvae surrounded by lymphocytes, eosonophil leukocytes and macrophages. The migration of B. transfuga larvae in spleen, kidneys and uterus of infected mice appears to have not been reported by previous workers. The possible role of B. Transfuga larvae in the visceral larval migrans syndrome is discussed.