Molecular and Histopathological Diagnosis of Bovine Viral Diarrhea Virus in a Dairy Cattle Farm Associated with an Abortion Storm

Background: Bovine viral diarrhea (BVD) which caused by a pestivirus, results in huge economic losses through abortion, weight loss, drop in milk production and even death of the affected animal. Reproductive disorders due to the virus infection are common in unvaccinated herds which are predominant causes of dairy cattle exclusion. The present study diagnosed BVD infection associated with an abortion storm in a farm following vaccination cessation. In addition, the present report investigated a variety of the disease complications other than abortion and it emphasized on the elimination of all the risk factors before any interruption in vaccination plan. Methods: The specimens were collected from 66 aborted fetuses and examined by real-time RT-PCR and histopathological methods for the presence of BVD virus. Results: Real-time RT-PCR detected BVDV in 47.14% of the aborted fetuses. The lesions of BVD were visible in the samples obtained from aborted fetuses. Conclusion: In the studied herd, we could see several complications of BVD such as infertility, abortion and agalactia. Each of the disorder has significant economic losses on dairy cattle herds, so it is necessary to implement control programs such as biosecurity and monitoring before any decision to stop vaccination.