The Yukon government has euthanized five feral horses that tested positive for an incurable blood disease.
The horses were captured in April near Canyon Creek, west of Whitehorse, after they were found wandering around the Alaska Highway.
They were “wild by circumstance,” said Kevin Bowers, an agricultural development officer with the Yukon government.
All five were found to be infected with Equine Infectious Anemia.
“It’s a disease of considerable concern to the horse industry,” said Dr. Mary VanderKop, the Yukon’s chief veterinary officer.
EIA, or swamp fever as it’s commonly called, is a retrovirus that infects and is reproduced in a horse’s red blood cells. When the animal’s immune system attacks and destroys the infected cells, it causes anemia, a severe lack of red blood cells.
Without enough red blood cells, tissues and organs become starved for oxygen.
“When they’re first infected, they show some clinical signs of weakness, lack of appetite, depression, reduced exercise tolerance,” said VanderKop. “It’s of concern, I guess, because of how readily it’s spread form horse to horse.”
The disease is spread mainly by biting insects, but can also be transmitted by infected medical instruments, sexually and from mare to foal.
It’s a disease that is specific to equine species, like horses and donkeys, so there is no danger to other livestock or people.
Regardless, it is a disease that is taken seriously in Canada.
The Canadian Food Inspection Agency has a program to control the disease. It requires that any animals that test positive for EIA be destroyed or quarantined for life.
“There isn’t a vaccine for it and there is no treatment for it,” said VanderKop. “I think really that the responsible things for people to do is to test before purchase.”
That’s how the Yukon government found out the animals were infected.
When they were captured, the agriculture branch spent almost three weeks trying to track down the possible owners of the horses.
“We advertised locally up and down the highway,” said Bowers.
When nobody came forward, the government became the owner by default, he said.
They were then put up for sale, and at that time tested for EIA.
It took 10 days to get the test results back.
“The process is we take a blood sample, send it out to a lab. If they get a positive result, they are sent to, I believe, a laboratory in Quebec, where it’s double-tested to confirm the original results,” said Bowers.
When the tests came back positive, the horses were taken off the market, he said.
Yesterday, all five horses were shot.
Horses have been present in the territory since the late 1800s.
“A lot of time, they free-ranged in areas where there was sufficient foliage,” said Bowers.
But the territory is a different place now and free-ranging horses represent a danger to the public when they wander onto the road, he said.
Currently, the government estimates there are 12 to 15 more wild horses living west of Whitehorse.
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