Montana Requires Brucellosis Testing on Cattle from Wyoming’s Big Horn County



Montana will soon require a negative brucellosis test on Big Horn County cattle and domestic bison prior to importation into the state. This is due to Montana state animal health officials’ concerns regarding exposure of cattle and domestic bison to brucellosis seropositive elk in Wyoming’s Big Horn County – an area where Wyoming has documented brucellosis in elk since 2012. Should an animal become infected in this area of Wyoming, it might move untested across state boundaries and could complicate epidemiological investigations that attempt to identify the true source of exposure.  


Effective June 15, the same brucellosis testing requirements that apply to Montana's Designated Surveillance Area (DSA) shall apply to cattle and domestic bison imported into Montana from Big Horn County. All sexually intact males and females12 months of age and older shall be tested prior to import. Animals intended for breeding must be tested regardless of age.  


Big Horn County is designated by the Wyoming Livestock Board (WLSB) as a “Brucellosis Area of Concern” as a result of brucellosis seropositive elk being found on the western side of the Bighorn Mountains in Wyoming Game & Fish Department (WGFD) Hunt Areas 39, 40, and 41 over the past four years.


WLSB pays veterinarians to do brucellosis testing on cattle and domestic bison moving or changing ownership within the Wyoming DSA and Brucellosis Areas of Concern.


Producers are advised to check with their veterinarians to assure that they are in compliance with state-of-destination import requirements prior to exporting livestock to another state.



Source:  Wyoming Livestock Board



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