Colorado State University scientists use fertility know-how to revive Yellowstone bison

American bison--Courtesy of Andrew Smith CC BY 2.0

On Sunday, 10 purebred American bison whose ancestors were native to Yellowstone National Park were set free in the Soapstone Prairie Natural Area, which sits between the Rocky Mountains and Great Plains in Colorado. It was the first time in 150 years that the species had set foot in that region--and the feat was made possible by advanced reproductive and genetic technologies spearheaded at Colorado State University.

Jennifer Barfield, an assistant professor of reproductive physiology at CSU, called upon a variety of technologies to create a herd of bison that are free of brucellosis, a disease that's endemic to Yellowstone and that triggers abortion in the animals. The disease can also infect elk and cattle, and it can be passed on to people, who are often struck by severe fevers when they catch it.

Barfield employed in vitro fertilization and artificial insemination to breed bison with heirloom genetics from Yellowstone. She also used a special washing technique to rid sperm and embryos of the brucellosis bacteria.

The embryos were incubated, frozen, and eventually thawed and then implanted into bison surrogate mothers. All of the animals were tested for brucellosis again before being reintroduced to the wild.

Jack Rhyan, leader of the USDA's wildlife/livestock disease investigations team, said in a news story from CSU that he believes this is the first time such "assisted" reproductive technologies have been used in a wildlife conservation project. The CSU team hopes they have created a diverse set of bison genetics that will aid conservation efforts in other parts of the U.S.

The bison reintroduction project is part of CSU's One Health Initiative. One Health is a growing international movement aimed at bringing together scientists with diverse background to tackle conditions that affect animals, people and the environment. Barfield's project was funded by a One Health seed grant from the university, and it will also encompass research aimed at understanding how bison grazing behavior affects the local ecosystem, ranchers and visitors to the region.

- read more from CSU