and implanting it safely into a healthy, commercial bison with ancestral cattle genes.

A healthy male purebred bison calf was born at the zoo on June 20 this year.

Ultimately, the science means that more purebred bison could be created using this embryo transfer approach and from this calf – and other Yellowstone bison - for zoos, wildlife parks and others around the world. The Bronx Zoo participated in the project as part of an effort to expand its bison herd.

In October, Colorado State University reproductive physiologist Dr. Jennifer Barfield and her team nonsurgically implanted the embryo from a Yellowstone bison cow maintained at the CSU Animal Population Health Institute's wildlife research facility in Fort Collins. The bison are quarantined because of their potential exposure to disease, which afflicts manythat can afflict the bison population at Yellowstone," said Barfield, an assistant professor in the university's Department of Biomedical Sciences, part of the internationally known College of Veterinary Medicine and Biomedical Sciences. Barfield also worked with George Seidel, University Distinguished Professor, on the project.

"In Yellowstone, the bison do not have trouble reproducing," Barfield said. "It's the process of removing animals that have been exposed to disease from the park so that their valuable genetics can be incorporated into other herds or used to create new herds that is the problem. The Bronx Zoo has been a wonderful partner in this along with the American Prairie Reserve and the Animal and Plant Health Inspection Service of the USDA."

The American Prairie Reserve aims to create and manage a prairie-based wildlife