Tapeworms are becoming more of an issue in horses as we learn more about how they affect horse health. Some regions of the country have a greater risk of equine tapeworm problems. In the upper Midwest (Wisconsin and Minnesota), for instance, studies have shown more than 80% of the horse population has been exposed to tapeworms. What you need to do about this exposure, and why preventing tapeworm infections is important, will be covered in this article.
Horses can be host to three types of tapeworms, says Thomas Craig, DVM, MS, PhD, professor of Veterinary Parasitology at Texas A&M University, but the only one of consequence today in horses in the United States is Anoplocephala perfoliata.
“It grows to a length of 1.5 to three inches and is found near the junction between the small intestine and cecum,” says Craig.
Tapeworms are resistant to many dewormers. They are not affected at all by ivermectin or moxidectin. Prior to 2003, there were no products labeled by the Food and Drug Administration (FDA) for tapeworm control, and most horse owners didn’t worry about these worms. Today there are two compounds available for combating tapeworms, and many veterinarians feel horses should be treated once or twice a year.
Tapeworm infections are difficult to diagnose; you can’t always tell if horses have tapeworms by fecal or other checks. Many horse owners add a product for tapeworms to their rotational deworming schedule just to be safe.
There might be a new diagnostic test available soon that can show whether or not a horse actually has these worms.
Products for Tapeworms
Craig Reinemeyer, DVM, PhD, formerly on the faculty at the University of Tennessee College of Veterinary Medicine and now president of East Tennessee Clinical Research, has been performing studies on equine internal parasites–and drugs to c