National Coalition Urges Government to Halt Risky Experiment on Wild Wyoming Mustangs


Washington, DC - Late yesterday, the American Wild Horse Conservation (formerly American Wild Horse Preservation Campaign), a national coalition, sent a letter to the White House and top officials of the Bureau of Land Management’s (BLM’s) Wild Horse and Burro Program, urging the immediate cancellation of a dangerous experiment planned for herds of horses in Wyoming’s North Lander Complex.
In a strongly worded letter, AWHC attorney Katherine Meyer, from the public interest law firm Meyer, Glitzenstein and Crystal, criticized the BLM’s plan to administer a controversial experimental fertility-control vaccine, known as SpayVac, to 60 wild mares during a roundup scheduled to begin next month.
“The BLM is proceeding with a dangerous experiment on wild Wyoming mares, subjecting them to an unproven fertility drug with possible deleterious side effects and potential irreversibility,” said Patricia M. Fazio, Ph.D. of Cody, Wyoming, who conducted an expert assessment of the existing research on SpayVac for AWHC.
AWHC is urging BLM to scrap the proposed study in favor of using the PZP fertility control vaccine, which has proven safe and effective over decades of research and use in the field.
In the letter sent on behalf of AWHC, Meyer warned that limited research has been conducted on SpayVac use in horses, but the available data indicates that SpayVac causes mares to experience persistent uterine edema, making them vulnerable to infections, abnormal estrus cycles, ovarian changes, and prolonged, possibly permanent, infertility after just one shot.
Due to the lack of data on the safety and efficacy of SpayVac, the BLM itself began a 5-year study of the drug on captive horses at its Pauls Valley (Oklahoma) holding facility. The agency also asked the National Academy of Sciences (NAS) to review SpayVac and other fertility control options as part of its overall review of the federal wild horse and burro program.
On May 3, 2012, the NAS hosted a public presentation on SpayVac. One participant, Dr. Irwin Liu, the NAS panel’s consultant on equine reproductive biology and physiology, noted that a published research paper indicated 100% of the 12 mares studied had excessive edema three years after the SpayVac drug had been administered. He warned that further research into the side effects and reversibility of SpayVac is needed.
AWHC believes that the BLM should not proceed with a field trial of SpayVac until the Pauls Valley pen trial, still 2.5 years from completion, is concluded.
“The willingness of BLM to subject wild horses to a potentially dangerous experiment is indicative of this agency’s overall attitude toward the animals it is supposed to protect,” said Deniz Bolbol, AWHC Communications Director. “The agency is inoculating wild mares with a drug that has been shown to have potentially serious side effects, then sending them back to the wild, in a vast and rugged habitat that will make it impossible to conduct follow-up studies or deliver treatment if needed.”
The agency’s sale of thousands of wild horses to a known horse slaughterer was recently exposed. AWHC has also been forced to repeatedly file lawsuits to stop the BLM from sterilizing wild horses. In a Wyoming lawsuit, AWHC prevented the BLM from converting two wild free-roaming horse populations to herds of castrated stallions. In Nevada, an AWHC lawsuit stopped the agency from castrating hundreds of wild free-roaming stallions and from “zeroing out” (eradicating all horses from) a designated Herd Area.
The American Wild Horse Conservation (formerly American Wild Horse Preservation Campaign) is a coalition of more than 50 horse advocacy, public interest, and conservation organizations dedicated to preserving the American wild horse in viable, free-roaming herds for generations to come.