Seroprevalence of BHV-1 (bovine herpesvirus type 1) among non-vaccinated dairy cattle herds with respiratory disorders.

The objective of this study was to estimate a herd-level seroprevalence of bovine herpesvirus type 1 (BHV-1) in herds with clinical symptoms of the respiratory tract. Eighty-three herds with suspected BHV-1 infection were selected and divided into two categories with respect to their size: small (n = 27) and large herds (n = 56). Samples were collected from calves, heifers and cows older than 24 months. Seroprevalence was determined using the gB ELISA test. The herd level seroprevalence was estimated as 53% (44/83) in the tested herds, 11.1% (3/27) in the small herds and 73.2% (41/56) in the large herds. Our study suggests that the current biosecurity measures still warrant improvement.