Performance of calves born to beef cows seropositive but subclinical for bovine leukosis virus

摘要

Calves from a commercial beef herd wereevaluated for weight gain differences basedupon the bovine leukosis virus (BLV) serological status of their dams. One hundredforty-two multiparous cows from a commercialbeef herd were tested for BLV by agar gelimmunodiffusion. Eighty-nine cows (62.6%)were found to be seropositive for BLV.Weights were collected from all calves atweaning, from heifers on the date when selection of replacement heifers was made, and from steers on the day of harvest after being fed to finish weight in a feedlot. Offspring from seronegative cows tended to have heavier weaning weights (+17 lb) and heifer selection weights (+31 lb) than those from seropositive cows.