Submitted to: Research Workers in Animal Diseases Conference Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 10/10/1997
Publication Date: N/A
Technical Abstract: Approximately 50% of bison bulls within Yellowstone National Park are seropositive for brucellosis. As this population may need to be addressed to manage the brucellosis problem in the YNP Area, two studies were initiated to evaluate the persistence of B. abortus strain RB51 in adult bison bulls. In both studies, bison bulls of between 2 and 3 years of age were hand (n=32) or ballistically vaccinated (n=20) with 10(10) CFU of strain RB51. A separate group of bison in both studies (n=24) were innoculated with sterile saline. No clinical signs or gross lesions were noted throughout the study. Serologic titers on a dot blot assay were greater for vaccinates when compared to nonvaccinated bison and were greater than titers reported from studies using similar dosages of strain RB51 in bison calves. Lymphocyte proliferative responses to irradiated RB51 bacteria were demonstrated in bison beginning at 14 weeks after vaccination. Strain RB51 vaccination was associated with transient localization of the vaccine strain in the reproductive tissues of some bison. The results of these studies suggest that strain RB51 is clinically safe in adult bison bulls but that transient localization in the reproductive tissues and shedding of the vaccine strain in the semen can occur in some bison.