Isolation of Bovine Herpesvirus-1 (BoHV-1) From Latently Infected/Carrier Cattle in Ahvaz

Bovine herpesvirus 1 (BoHV-1) is one of the most important infectious viruses of cattle which is considered as the causative agent of several clinical conditions in this species. Hence, we tried to isolate a local strain of the virus from carrier cattle in Ahvaz based on a strategy for reactivation of the latent infection in hosts having antibodies against the virus. Thus, 20 cattle were examined to identify seropositive animals using virus neutralization test (VNT). Afterward, 4 out of 8 seropositive cattle were selected and experimentally stressed by daily injection of Dexamethasone up to five days. Following the injection of Dexamethasone, nasal swabs were collected during 10 days and applied for virus isolation in cell culture. The results showed that one of the stress-induced animals shed the virus on days 8, 9 and 10 after injection of Dexamethasone. Identification of the reactivated virus was carried out based on the virus-induced cytopathic effects in cell culture and PCR and the results were confirmed by sequencing of the PCR product. Isolation of such a local strain of the virus can improve our understanding about circulating BoHV-1 strains in the country.