Tapeworm in horses, or worms in general, are not exactly a dinner table subject. But for horse owners, worms are a part of regular care and maintenance. Tapeworms are an easily treated parasite, and typically well-tolerated by horses, all things considered. Here’s a quick breakdown on tapeworms in horses:
What are Tapeworms?
Equine tapeworms (Anoplocephala perfoliata) sound horrifying. But the truth is, tapeworms are typically present wherever horses have access to pasture or turnout. There are three species of tapeworms that will infect horses. The most common is A. perfoliata. This is a short yellowish-greenish tapeworm triangular in shape. Large mature worms can grow up to around 8 centimeters in length. They use their heads to secure themselves on the mucus of the host horse and then proceed to absorb nutrition through the parasite’s cuticle.
Tapeworm in Horses Life Cycle
Unlike other parasites, tapeworms have an indirect life cycle. They use an intermediate host for the development state. In the case of the most common tapeworm, it is an oribatid mite. Unfortunately for horses and other grazing animals, these mites are frequently found in pastures and hay. A horse digests the mite containing tapeworm larvae, which later develop in the primary horse host. Mature tapeworms will shed eggs by 10 weeks. Unlike many other parasites, tapeworms do not appear to be a seasonal-specific problem.
Many horses with tapeworms show little to no symptoms. Most horses will not even experience discomfort. However, new studies have shown chronic parasites put horses at a greater risk for spasmodic colic and impaction at the lower end of the small intestine. In most cases, horses will remain asymptomatic. In some cases, horses may experience digestive issues or upset. Segments of the tapeworm will eventually separate to release eggs inside the host, and the proglottids are seen in their poop.
Testing for Horse Tapeworm
The standard testing for most equine parasites is a fecal test. But recently experts found the McMaster technique of counting eggs in fecal matter misses more than 90% of infected horses! Veterinarians can also detect tapeworm antibodies in saliva and serum. However, tapeworms do not normally need a formal diagnosis. They are adequately treated by regular deworming schedules.
Treatment for Tapeworm in Horses
The treatment for equine tapeworms is an over-the-counter dewormer. Of the multiple dewormers available, only two treat tapeworms. The first is praziquantel. This is available as a stand-alone dewormer or in combination with ivermectin or moxidectin. This is the most effective treatment against tapeworms. The other dewormer is pyrantel pamoate. A single dose will reduce the worm load, but doesn’t possess the same effectivity. For maximum effectivity, proper administration should be a double-dose.
It is important to speak to your veterinarian about a deworming schedule that works for you and your horse. This will take several factors into account, including a horse’s propensity to carry a worm load, travel, exposure, environment, and other parasite risks. For tapeworm specific deworming, EquiMax recommends treatment every 6 months- fall and late spring. Current guidelines on parasite control by the American Association of Equine Practitioners can be found here.
For more information on Deworming Schedules for Horses
Although no longer considered harmless, tapeworms can cause problems if left untreated. It is important to determine a regular deworming schedule for the prevention and treatment of parasites. Luckily, tapeworms are easy to manage and do not typically require veterinary assistance.
Do you have friends with horses? Fall is a good time to deworm- be sure to share this article!