Living with Brucellosis exposure in our Montana bison herds
By Tom Bragg
Brucellosis continues to be a highly regulated disease in the livestock industry. When Brucella abortus is present, it is associated with abortions in Cattle, Bison, and Elk. Through decades of regulatory work and cooperating with state agencies and producers, the US Dept. of Agriculture has helped eliminate B. abortus from most of the country. There remain populations of wild elk and bison in the Greater Yellowstone Ecosystem that maintain a baseline level of infection in the area. Turner Enterprises has 3 ranches with bison operations in this area, which is identified by the Montana Dept. of Livestock as the Brucellosis Designated Surveillance Area (DSA). As a result, exposure to this pathogen is possible at certain times of year as elk move throughout the DSA. Finding evidence of exposure to B. abortus through blood tests in these herds is not uncommon, and at least one property is frequently under quarantine.
Understanding that these ranches are continually exposed to elk that have a possibility of transmitting Brucellosis, we developed a plan to maintain bison productivity and marketability while under a level of quarantine. To reduce exposure to potentially infectious tissues such as elk afterbirth or aborted elk fetuses, these ranches plan their grazing to avoid areas used by elk before and during the elk calving season. In addition, the primary property has a well-established On-Ranch Feeding operation, and all bison from that ranch are marketed as a fed or meat animals and sent directly to slaughter under our Brucellosis Management Plan.
Turner Enterprises’ Montana ranches under quarantine follow a Brucellosis Management Plan established in cooperation with Federal and State Regulators to address animal movements, vaccinations, testing, and death loss. Turner Enterprises’ ranch and veterinary personnel work closely with State and Federal staff to execute the cooperative Brucellosis Management Plan.
In addition, it is not uncommon to have a false positive result when testing bison for exposure to Brucellosis. The Team at Turner Enterprises is working with Federal Veterinarians and Researchers to develop improved testing methods that are more reflective of the unique way bison respond to Brucellosis vaccination vs. B. Abortus exposure in their environment.
Turner Enterprises accepts there are challenges to operating a private bison enterprise among brucellosis-infected public wildlife. Through proactive ranch management, alternative marketing strategies, and cooperation with State and Federal agencies, TEI has found a way to successfully address this animal health challenge.