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Health Canada says it has approved the use of a contraceptive vaccine for testing on free-roaming horses in Alberta.
The Alberta government says horse numbers in some parts of the province have reached “unacceptable” levels. The province believes it is important to control horse populations to ensure they do not overly impact cattle and wildlife pastures.
Contraception is one of the measures outlined in the province’s feral horse management program, which also includes removing horses from the wild and putting horses up for adoption as a population control strategy.
The Alberta government received “research authorization” for the use of the SpayVac-Equid contraceptive vaccine in late August, a Health Canada spokesperson confirmed to CBC News.
“This research permit allows the product to be studied in wild horses; it does not constitute approval for general use,” the federal agency said in a statement.
WATCH | Are there too many wild horses in Alberta?:
The Alberta government says it is “currently reviewing approval details” for contraception for horses.
“The Government of Alberta continues to work with stakeholders and advisory committee members to implement management measures in a safe, humane and science-based manner,” the province’s Department of Forestry and Parks said in a statement.
“Currently, these actions are limited to ongoing data collection and implementation.”
The province’s latest wild horse survey found 2,072 wild horses in Alberta’s six horse breeding zones this year — the highest number ever counted — with population levels in the Sundre, Ghost River, Elbow and Clearwater zones “not being ecologically sustainable.”
The Alberta government considers horses stray animals and not wild animals.
The new strategy aims to build on previous attempts
In 2014, the province and the Alberta Wild Horse Society launched a pilot project on contraception to determine how effective they could be in controlling the population.
Thanks to this program, a vaccine was created called ZoneStat-H – different from what is currently used, but contains the same active ingredient porcine zone pellucida — controlled shooting at wild horses with darts.
From 2015 to 2017, 87 mares received an initial dose, 17 received a booster dose, and five received a third dose. Of the 17 vaccinated mares that were actively monitored, only one was confirmed to have given birth.
The project found that contraception was very expensive (estimated at $1,180 per dose) and difficult due to the rugged terrain in which the horses live, making it difficult to track the horses and administer booster shots.
The province also cited studies showing that between 45 and 84 per cent of the entire female horse population would need to be on birth control for any significant population decline.
Wild horses have long been present in Alberta. Many ranchers consider them a nuisance, and some want to remove them from the land. The non-profit organization Wild Horses of Alberta Society is dedicated to rescuing these animals and finding new homes for them. They teamed up with veterinary students from the University of Calgary to manage their populations.
This time, Alberta Wild Horse Society president Jack Nicol says the plan is to capture the horses, hand-inject the vaccine, and then release them back into the wild, tagging the vaccinated horses to help identify them in the future.
“We believe this is necessary to be able to keep horses there without anyone having to take drastic measures to reduce the number,” he said.
Nikol said this method has an 85 to 95 percent success rate, prevents conception for three to four years, and does not change herd dynamics. SpayVac-Equid also does not require repeated shots, unlike the previous contraceptive.
“If the mare is pregnant at the time of vaccination, it will not change anything,” he said.
Nicol said the goal is to launch the contraception project this fall as part of a new population control strategy that will also include capturing a limited number of young stallions and removing them from the wild.
“They never want the horses to leave the land,” Nicol said of the provincial government. “They just want to be able to control the animals and their numbers as much as possible to try to keep all land users happy. It’s quite difficult to make everyone happy, but they try.”
The Alberta Wild Horse Society currently rescues and rehabilitates horses, including those that stray onto private property, and places them up for adoption. Nicol said the society has adopted more than 200 horses since its launch in 2002.