[Neospora abortion in cattle in The Netherlands]

Three cases of bovine protozoal abortion at three different dairy farms are reported. Multiple abortions had occurred, on two farms, and a sporadic abortion on the third farm. Histopathological examination of foetal tissues revealed a distinctive multifocal necrotising encephalitis as well as focal inflammatory lesions in the myocardium, liver, kidney and lung. In one foetus protozoal tissue cysts were found in the brain and individual and clustered tachyzoites were seen in brain, and lung. In another foetus a cluster of tachyzoites was seen in a section of a placentoma. Immunohistochemically, tissue cysts as well as tachyzoites reacted with Neospora caninum antiserum. Tachyzoites were also detected in the brain lesions of the other two foetuses. The preliminary results of a histopathological survey of aborted bovine foetuses indicate that this protozoal infection may be an important cause of bovine abortion in The Netherlands.