Stillbirths Associated with Neospora caninum and BVDV type II in Dairy Heifers

Abstract

Although stillbirths can contribute significantly to dairy heifer replacement costs, causes of most stillbirths are unknown, partly because of the high diagnostic costs and difficulty interpreting results. Costs can be prohibitive for necropsy and diagnostic work-up of dead calves of sufficient numbers to obtain a confident herd diagnosis, and interpretation of case-control-type of serology data for cows at calving can be confusing. Even though there has been little documentation, agents typically considered when investigating a stillbirth problem include leptospira, Bovine Viral Diarrhea Virus (BVDV), Infectious Bovine Rhinotracheitis Virus (IBRV), and Neospora caninum. The objective of the present study was to assess, using a prospective diagnostic approach, the extent to which these agents were associated with a high rate of stillbirths that had appeared among heifers on a large dairy.