Contraception of bison by GnRH vaccine: a possible means of decreasing transmission of brucellosis in bison

J Wildl Dis. 2004 Oct;40(4):725-30. doi: 10.7589/0090-3558-40.4.725.

Abstract

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.

MeSH terms

  • Abortion, Veterinary / prevention & control
  • Animals
  • Animals, Newborn / microbiology
  • Bison / physiology*
  • Brucellosis / prevention & control
  • Brucellosis / transmission
  • Brucellosis / veterinary
  • Contraception, Immunologic / methods
  • Contraception, Immunologic / veterinary*
  • Female
  • Gonadotropin-Releasing Hormone / immunology*
  • Gonadotropin-Releasing Hormone / pharmacology
  • Infectious Disease Transmission, Vertical / prevention & control
  • Infectious Disease Transmission, Vertical / veterinary
  • Pregnancy
  • Pregnancy Rate
  • Safety
  • Vaccines, Contraceptive / pharmacology*

Substances

  • Vaccines, Contraceptive
  • Gonadotropin-Releasing Hormone