Seroprevalence of Neospora caninum in Hérens cows in the canton Valais – A prospective, representative field study

Neospora caninum is a global cause of abortion in cattle. Infection occurs either vertically - from the mother to the foetus - or horizontally through the oral ingestion of -oocysts via contaminated feed or water. Infected cows may abort or give birth to seropositive calves that are already infected in utero. Both the dams and their calves remain permanently infected. As Hérens cows often have a high emotional value for their owners, animals are often re-bred after abortions in an attempt to achieve a new pregnancy. The aim of this study was to determine the seroprevalence of Neospora caninum in female Hérens cows in the canton Valais. Antibody testing of 425 animals from 86 farms revealed 13 Neospora caninum-positive animals from 12 farms. In our sample, this corresponded to a seroprevalence of 3,1 % (95 % C.I. 1,7-5,3 %) at the individual animal level and 14 % (95 % C.I. 7,8-23,5 %) at the farm level. No significant risk factors could be identified at either the individual animal or farm level.