Transmission of bluetongue virus by intrauterine inoculation or insemination of virus-containing bovine semen.

Bluetongue virus was inoculated transcervically into the uterine body of estrous heifers to determine whether infection could be readily established by this route of exposure. Two strains of the virus were transmitted by intrauterine deposition. Nine heifers were inseminated at estrus with 0.5 ml of processed, frozen-thawed semen that had been collected during the course of viremia in an experimentally infected bull. This semen contained titratable quantities of bluetongue virus. Of 9 inseminated heifers, 6 became pregnant and 3 became viremic and developed antibody to bluetongue virus. An additional heifer seroconverted, but did not become detectably viremic. Evidence of fetal infection was not present in the heifer that became infected and pregnant or in the 5 heifers that became pregnant, but were not infected.