DETECTION OF CYTOPATHIC BOVINE VIRAL DIARRHEA VIRUS IN THE OVARIES OFCATTLE FOLLOWING IMMUNIZATION WITH A MODIFIED-LIVE BOVINE VIRAL DIARRHEA VIRUS-VACCINE

Economic loss from infection with bovine viral diarrhea virus (BVDV) i s of worldwide concern. The unique pathogenesis and antigenic variabil ity of BVDV have made this virus challenging to control. Vaccination p rograms are a major component of control and prevention strategies. Bo th killed and modified live vaccines are commercially available. Choic e between killed and modified live vaccines is controversial. Of major concern is the safety of modified Live vaccines. Little information i s available on their tissue tropism and potential for causing patholog y, especially with respect to the reproductive system. The objective o f this study was to determine if BVDV could be detected in the ovary o f cattle following immunization with a modified Live BVDV vaccine. In 2 separate trials, ii heifers and 4 mature cows were immunized with a modified live BVDV vaccine and ovaries were removed between 7 and 30 d ays postvaccination. Cytopathic BVDV was isolated from ovaries removed on days 8, 10, and 12. BVDV antigen was detected using immunohistoche mistry on days 10-30. These findings are significant because replicati on of virus in the ovary could cause ovarian dysfunction, resulting in reduced fertility.