Porcine zona pellucida (PZP) fertility control for feral horse populations offers a humane alternative to roundups that maintains herd social structure while achieving population management goals.
PZP fertility control maintains the welfare of individual horses while achieving population management goals. Mares continue normal social behavior, seasonal movement, and herd dynamics without the acute stress of roundup and handling events. The long-term Assateague success demonstrates that stable, socially intact feral horse populations can be maintained through fertility control, making roundup-based management an unnecessary welfare cost in areas where PZP programs can be sustained.