The aim of the present study was to determine the evolution of the levels of anti-BHV-1 colostral antibodies. Serum samples were obtained at 6, 12 and 24 hours post-birth, weekly through the 63rd day of age, and monthly through the 180rd day. The study utilized the serum neutralization test (SN). The colostral antibodies against BHV-1 declined gradually: the first negativo samples were obseved at day 28, and the geometric mean titer of antibodies (GMT) was estimated to be £1:2 at day 180. These data suggest that serology for BHV-1 (using the SN) should be used only in calves older then six months.
bovine herpesvirus type 1; colostral immunity