The PZP vaccine is one way the BLM manages population control of wild horses and burros on public lands. | Photo: iStock

On the afternoon of July 24, bill HR 7608 passed the U.S. House of Representatives with an amendment designating $11 million of the Bureau of Land Management’s budget for the Wild Horse and Burro Program to be used to implement the porcine zona pellucida (PZP) immunocontraception fertility suppression vaccine.

“This is significant in part because the BLM would be required to direct that funding for PZP fertility control,” said Joanna Grossman, equine program manager for the Animal Welfare Institute. “In past years, there has been vague language directing the BLM to pursue humane or politically viable and effective options.”

The PZP vaccine suppresses fertility and acts as a contraception in animals such as horses and elephants. It’s one way the BLM manages population control of wild horses and burros on public