DNA Tests Indicate Yellowstone National Park Elk, Not Bison, Most Likely To Spread Brucellosis

While bison in Yellowstone National Park draw the most attention for the potential to spread brucellosis to livestock in the surrounding states of Montana, Idaho, and Wyoming, genetic studies indicate that elk are most likely behind the disease's spread in the region. A small story in the fall issue of Yellowstone Science discusses that conclusion. A DNA genotyping study conducted in 2009, and which was just recently published in the Journal of Wildlife Diseases, examined samples from 10 bison, 25 elk, and 23 cattle collected in the greater Yellowstone area between 1992 and 2003 and found that DNA markers for Brucella abortus were nearly identical in elk and cattle but "highly divergent" from those in bison. "The data, which suggest that elk rather than bison are most likely the origin of recent outbreaks of brucellosis in Greater Yellowstone cattle, are consistent with the fact that elk comingle with cattle more often than do the wild bison, which have been managed to prevent dispersal outside established conservation areas," notes the Yellowstone Science article...more