— “the EPA in 2012 approved the most common vaccine that uses PZP, zonastat-H, but mares have to be vaccinated every year for it to remain highly effective.” http://www.sltrib.com/sltrib/news/58029163-78/wild-horses-control-blm.html.csp
— “the EPA in 2012 approved the most common vaccine that uses PZP, zonastat-H, but mares have to be vaccinated every year for it to remain highly effective.” http://www.sltrib.com/sltrib/news/58029163-78/wild-horses-control-blm.html.csp