Diagnosis of BVD infections can be made in the fetus or the cow. The fetus can become mummified, autolyzed or be delivered fresh following infections. The fetus should be submitted to the diagnostic laboratory for examination. Paired blood samples can also be checked for changing titers. However, often the abortion is noted long after the infection occurred making blood titer difficult to interpret.
Prevention involves increased attention to biosecurity and enhanced immunity following vaccination.
The source of BVD infections are infected cows shedding the virus. The closed herd concept or quarantine of newly purchased animals can prevent infections. The most common protection is by vaccination. Calves vaccinated before 6 months of age should be revaccinated prior to breeding. Killed BVD vaccines are also used and are safe to use in pregn ant cows.