A serological survey of antibodies against bovine herpesvirus-1 in yak (Poephagus grunniens) in Arunachal Pradesh in India.

Serum samples were collected from 254 yak (Poephagus grunniens, presently Bos grunniens) in different yak tracts of India. These samples were then screened by virus neutralisation test (VNT) and avidin-biotin enzyme-linked immunosorbent assay (AB-ELISA) to study the seroprevalence of antibodies against bovine herpesvirus type 1 (BHV-1). The overall seroprevalence in yak was found to be 41% (105) by VNT and AB-ELISA. The sex of the animal, whether it was on a farm or free-ranging and the location of the different yak tracts did not seem to have any effect on seroprevalence. However, seroprevalence was found to increase with the age of the animals, being highest in yak older than three years of age (49%). Yak generally share feeding, watering and grazing areas with other domestic and wild animals and this common ecological niche is thought to be a possible avenue of infection. This is the first time that the seroprevalence of antibodies against BHV-1 has been studied in yak in India.