Contagious equine disease appearing in central Kansas, local horse breeders safe for now
By ROBERT PIERCE • Daily Leader
At least six mares in south-central Kansas were recently reported to be part of a growing number of horses in 28 states exposed to a contagious equine disease.
The U.S. Department of Agriculture said 12 stallions and 83 mares in
28 states have contracted the condition, known as contagious equine metritis, since it first emerged in December.
Local officials, including K-State agent Mike Hanson and Starla Young of Seward County Farm Bureau, who, along with her family, raises horses, have seen little in the way of the problem in the area. But Joann Kouba, an associate professor of animal science at K-State, said the condition is hard to detect, which means it could be present without the owner’s knowledge.
“It’s what we would consider a venereal disease if you want to put a human spin on it,” she said. “That’s probably the easiest way to discuss it with most people. It’s a disease that gets passed along primarily from stallions to mares through breeding.”
Kouba said CEM is a bacterial problem.
“In stallions, you generally don’t see any kind of graphical symptoms,” she said. “There’s no visible kind of signs that a stallion might be infected with it. That’s why we’re kind of running into the problem right now within the United States.”
Kouba said this means more than likely a stallion was brought into the country whose owner had no knowledge of CEM.
“It’s one that generally horses are being tested for, so that you’re not transmitting it across into countries,” she said. “Stallions themselves don’t show any physical signs. There’s no impact to them.”
This means, Kouba said, it is generally hard for most horse owners to realize that a stallion might be harboring this particular bacteria.
“Then they come in and pass it on to mares when they get bred,” she said. “The bigger problem with the mares is that you can get some pretty severe inflammation. They’ll essentially develop a reaction.
They’ll have an immune reaction to the bacteria once it gets deposited in the vagina and the uterus during breeding.”
As a horse’s immune system tries to rid its body of CEM, the creatures usually develop severe inflammation, according to Kouba.
“That takes a little while to get over with the mares,” she said. “In most cases, it’s relatively easy to cure. It’s just going to take a little while, and you’ve got to have them on antibiotics. They’ll culture it and find out that’s what it is and start to treat it.”
Kouba said, however, the chances of death are very minimal, adding she has never heard of a horse dying from CEM.
“When you hear contagious disease, people get worried, but it’s not something that’s going to be killing horses,” she said. “It can be easily spread, and when a mare gets it, then they’ve got this infection that essentially you have to clear up.”
Kouba said this could take some time, and it could take the horse out of breeding for as much as a year.
“That’s kind of tricky,” she said. “There’s no vaccine for it. It’s not something we can treat.”
Kouba said there is much in the way of treatment for mares who get CEM.
“You’ve got to get rid of it,” she said. “Test them frequently to make sure they’re no longer carriers and try to prevent it and isolate it. A lot of the horses that are coming down with it are being quarantined, and that’s just because you don’t want it to be spread in between horses. The bacteria is going to be in the discharge that these mares will be having.”
Kouba said some mares can become chronic carriers of CEM, but they will not show any symptoms at all, meaning they are merely harboring the condition.
“It’s possible that there are other horses out in the country that have it, but we haven’t caught them,” she said. “It’s something that we do test for, and if you’re importing horses, it’s one that we try to regulate. We see it in Europe, but we haven’t dealt with it much in the United States.”
Kouba said CEM is not breed specific, adding it occurs in both stallions and mares.
“Stallions are carriers, but they just harbor the bacteria,” she said. “The mares are the ones that, when they get bred and when they get a reaction to the bacteria, trigger the immune system to fight off this infection by trying to get rid of it. This is when you get this inflammation that sets up.”
Kouba said while horse owners should be concerned, they should primarily pay attention to restrictions on whether or not they can move or transport the animal.
“There are pretty severe and strict USDA guidelines and vet requirements for horses that are identified that have this problem,”
she said. “It’s highly contagious, so you can spread this fairly easily. In terms of the overall consequence to the horse, I’d rather have a horse any day get CEM than come down with West Nile for example. There’s no comparison.”