Isolation of Coxiella burnetii from bull semen.

Previous observations on the dissemination of Coxiella burnetii between laboratory animals strongly support the hypothesis of venereal transmission. Serum and semen samples, from 57 bulls used for artificial insemination, were assayed for specific C. burnetii phase II antibodies and the presence of the organism respectively. Viable C. burnetii were detected in the semen of seropositive bulls. These findings indicate the possibility of sexual transmission of C. burnetii between cattle and further our knowledge of the epidemiology of the organism. The procedures used for investigations into the source of infection and route of tran-mission should be modified to take these findings into account.