0 Lowell A. Miller Rhyan, Jack C. Drew, Mark 2004 Journal of Wildlife Diseases 40 725-730 October 2004 transmission, brucellosis, risk, vaccination, bison, immunocontraception, GnRH vaccine, gonadotropin-releasing hormone vaccine, vaccine Preventing pregnancy in brucellosis-infected bison (Bison bison) provides a potential means of preventing transmission of disease. To determine whether a gonadotropin-releasing hormone (GnRH) vaccine was effective in reducing pregnancy in bison and to study the safety of injecting GnRH in pregnant bison, a study was conducted at the Idaho Fish and Game Wildlife Health Laboratory in Caldwell, Idaho (USA). Four pregnant and two nonpregnant female bison were given a single injection of GnRH vaccine, and five pregnant adult females were given a sham injection that contained only adjuvant. Three of the GnRH-vaccinated bison that were pregnant at the time of vaccination delivered healthy calves. One treated bison had dystocia that resulted in a dead calf. All control bison delivered healthy calves. After calving, females of both groups were exposed to two bulls. Treated bison were palpated 6 wk after exposure to the bulls, and blood was drawn for pregnancy-specific protein B analysis. The six treated bison were not pregnant. The sham-treated bison became pregnant and delivered viable calves. This study demonstrates that a single dose of GnRH vaccine is effective in preventing pregnancy in female bison for at least 1 yr. Found in Bison Library and online, pdf on computerNatureBib ID: 652302 http://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=1367&context=icwdm_usdanwrc