Isolation and Molecular Characterization of Bovine Herpes Virus Type 1 from Upper Respiratory Tract of Bovines

Background: Bovine herpes virus type 1 (BoHV-1) the causative agent of Infectious bovine rhinotracheitis (IBR) is of great concern to dairy farmers and veterinarians due to great economic impact caused by the virus in terms of loss of production and abortion. Therefore, the study was planned to detect the virus circulating in the bovine population of the region under study. This virus is an important pathogen of bovine respiratory diseases. The aim of the present study was to isolate the BoHV-1 virus from the upper respiratory tract of bovines. Methods: A total of 13 nasal swab samples were subjected to virus isolation in Madin Darby Bovine Kidney (MDBK) cells lines. A PCR assay was applied to confirm the BoHV-1 DNA by targeting gI glycoprotein gene in isolates. Result: Total two IBR virus isolates were recovered from 13 nasal swab samples of bovines. Both isolates exhibited cytopathic effects i.e. clumping and rounding of cells. A 468 base pair of amplified product from both isolates confirmed the IBR virus in gI gene specific PCR for BoHV-1. This study concludes that IBR virus exists among cattle population of Punjab and it is present in the upper respiratory tract of infected animal and shed through respiratory route. The PCR detection assay for detection of BoHV-1 from nasal swab samples is considerably more sensitive than virus isolation.