Failure to detect bovine immunodeficiency virus contamination of stud bull spermatozoa, blood leukocytes, or semen leukocytes in samples supplied by artificial insemination centers.

OBJECTIVE: To determine whether bovine immunodeficiency virus (BIV) infection could be detected in spermatozoa, blood leukocytes, or semen leukocytes from stud bulls in artificial insemination centers. ANIMALS: 30 bulls at 3 artificial insemination centers. PROCEDURE: Polymerase chain reaction testing that used 3 sets of primer pairs targeting pol and env regions of the BIV proviral genome was performed on DNA extracted from semen leukocytes, spermatozoa, and blood leukocytes from each bull. Southern blot analysis was performed to increase sensitivity of detection. Western blot analysis of plasma samples was used to detect antibodies against BIV.
RESULTS: BIV provirus was not detected in DNA samples obtained from semen leukocytes, spermatozoa, or blood leukocytes, and antibodies against BIV were not detected. CONCLUSIONS AND CLINICAL RELEVANCE: Contrary to our report of high point prevalence of BIV contamination of semen from a single artificial insemination center, bulls of the study reported here did not appear to be infected. Maximum risk of BIV infection in similar bulls was estimated at 10% with a confidence level of 95%.