It’s spring, and you know exactly what kind of worming program for horses to follow. Deworm all your horses, do it on a frequent and regular equine worming schedule, and have horse dewormer rotation through different classes for deworming horses. Right?
Wrong. Equine parasitologists now advise you to rethink the traditional rotational horse deworming protocol. Conventional wisdom has changed, and it's forcing a need to relearn what we've assumed to be "fact" about horse deworming strategies. Read on for a quick fact check that before you change your horse dewormer schedule again.
FACT. Horse dewormer rotation is not only unnecessary, it actually may be harmful. "Most horse owners think they have been doing the right thing to fight resistance by rotating equine deworming products. But using several products, some of which may not be effective for parasites infecting horses on your farm, doesn't work," says Frank Hurtig, DVM, MBA, director, Merial Large Animal Veterinary Services. Hurtig added that this practice may actually contribute to resistance in any worming program for horses.
To learn more about deworming, download our FREE guide—Deworming Your Horse: How to find the best deworming schedule for you and your horse.
Rotational horse deworming, according to Dr. Hurtig, is an outdated practice that originated primarily because early horse deworming products weren't entirely effective against all worms. They also believed horse dewormer rotation would help keep resistant worm populations from arising on a farm or in an area, but it does not appear to be slowing the development of resistance.
Resistant worms occur by chance but they cannot be diagnosed on a farm until they make up at least 25 percent of the worm population. By then, it is too late to correct through a standard horse deworming program.
This fact highlights the importance of horse deworming only for the ones that need it and utilizing fecal egg count reduction tests (FECRTs) as part of an overall strategic equine deworming protocol. By using this horse deworming strategy, you can regularly monitor the efficacy of your equine deworming program and the horse deworming products you are using, as well as help determine if resistance exists on your farm.
Here’s to your horse’s health.