Submitted to: Wildlife Disease Association Annual Meeting
Publication Type: Abstract Only
Publication Acceptance Date: 8/11/2003
Publication Date: 8/11/2003
Citation: Olsen, S.C., Stoffregen, W.C., Waters, W.R. 2003. Immunologic responses and efficacy of hand or ballistic vaccination of bison (bison bison) with brucella abortus strain rb51(abstact). Wildlife Disease Association. Paper No. 108.
Technical Abstract: The prevalence of brucellosis in bison within Yellowstone National Park in the United States has raised concerns in regards to possible transmission to domestic livestock. In a series of studies conducted at our laboratory, we have characterized immunologic responses of bison calves to hand vaccination with Brucella abortus strain RB51 (SRB51), or ballistic vaccination with a commercially available biobullet in which a SRB51 pellet has been placed. In addition, the influence of ballistic delivery on immunologic responses was evaluated by comparing responses of bison ballistically inoculated with SRB51 to responses of bison in which a SRB51 biobullet was surgically placed intramuscularly. Immunologic responses evaluated included: antibody responses, proliferative responses by purified peripheral blood mononuclear cells (PBMC) to killed SRB51, interferon- production by PBMC, nitrous oxide production, and flow cytometric analysis of proliferating PBMC subsets. Antibody responses of hand and ballistic vaccinates were similar. However, cell-mediated responses tended to be greater in hand vaccinates as compared to ballistic vaccinates. Bison were pasture bred as 3 years and pregnancy status and days in gestation determined by rectal palpation. Based on rectal palpation data, bison were challenged between 170 and 180 days gestation by placing 1 x 107 CFU of Brucella abortus strain 2308 bilaterally on the conjunctiva. Following abortion or full-term parturition, bison cows and calves were euthanized and tissues collected for bacteriologic and histologic evaluation. Although hand vaccination and single ballistic vaccination reduced the incidence of abortion or fetal infection when compared to nonvaccinates, the ability to recover the challenge strain from maternal tissues at necropsy did not differ between vaccine and control treatments. Our data suggests that immunologic responses of bison to vaccination with RB51 differ dependent upon the route of vaccine delivery. Our data also suggests that vaccination of bison with RB51 can reduce the incidence of abortion and risk of transmission, and may be of value as a management tool in an Brucella-infected bison herd.