Serum antibodies against BHV-1 were studied, by the serum neutralization test, in cattle from Southem Brazil. Samples were collected from 2341 cattie from 112 farms that had reprodution problems. Positive results were obtained in 747 (31.9) cattie from 80 (71.31%) farms, given evidence of the expressivo vírus dissemination in cattie from this region.
BHV-1; serum neutralization test; serology