Bison and Brucellosis

A. A contagious disease in cattle, bison, elk, and other ungulates, Brucellosis abortus causes females to abort. Over the past 70 years, the federal government, states, and livestock growers have spent several billion dollars to eradicate brucellosis in cattle. Currently, all but two states have been designated by the U.S. Department of Agriculture (USDA) as "brucellosis-free." Montana cattle have been classified brucellosis-free since 1985.

A. Yes. While transmission of brucellosis from bison to cattle has never been documented in the wild, the disease has been transmitted from bison to cattle in a controlled environment. The disease has been transmitted from wild elk to cattle in the wild.

A. Today, most Montana livestock producers choose to vaccinate their replacement heifers annually and vaccination is mandatory for cattle in the Western and Northern Special Management Areas (SMA) adjacent to Yellowstone National Park. In addition, the Montana Department of Livestock recommends vaccination of cattle that could be exposed to infected wildlife, especially in the Greater Yellowstone Area. Among all 50 states, only Texas and Idaho do not have brucellosis-free status. Montana obtained its “brucellosis-free” status in 1985, a process that took 50 years and cost Montana ranchers more than $35 million dollars.