ENDEMIC PROTOZOAL ABORTIONS IN A DAIRY-COW HERD

Seventy cows in a 450-cow Holstein drylot dairy aborted from July 1990 through September 1992. Twenty of the 70 aborted fetuses were submitt ed for laboratory examination. The 20 fetuses, including one mummified fetus, had lesions suggestive of a protozoal etiology. Protozoa inclu ding Neospora spp., Sarcocystis spp., and an unidentified protozoan we re believed to be responsible for the abortions. Retrospectively, this herd had experienced an epidemic of abortions and had a history of on going abortions.