Remember Tapeworm Control this Spring

Before turning horses out on pasture this spring, remember to check with your veterinarian to ensure your deworming program includes tapeworm control.

Tapeworms are transmitted by an intermediate host, the oribatid mite, which lives on pastures. While grazing, horses can ingest the mites and become infected. Once infected, it takes the tapeworm about two to four months to mature inside the horse.

"Spring is a perfect time for transmission of the tapeworm," said Hoyt Cheramie, DVM, MS, manager of Veterinary Services at Merial. "Horses begin to get out and graze and may become infected with tapeworms, which can lead to colic."

Some research suggests that tapeworms, specifically Anoplocephala perfoliata, are associated with up to 80% of ileal impaction colic cases. Tapeworms can cause many other kinds of problems in the digestive system. For instance, tapeworms attach to the ileocecal area and cause inflammation, ulceration and bowel obstruction. In young horses, tapeworm infections can cause a potentially life-threatening condition known as intussusception, which is the telescoping of the intestine into itself.

Cheramie warns that these health concerns aren't just for a particular age or geographic area. Tapeworm infections can occur in horses of all ages, and tapeworms are common in grazing horses across the country. In fact, more than half of the horses in one survey had tapeworms. Infection rates were as high as 95% in the upper Midwest. In Southern states, infection rates were still as high as 84.3%.

"It doesn't matter where you live; tapeworms are likely a concern in your area," Cheramie said. "It's important to make sure parasite control programs include effective tapeworm control, but using a tapeworm control doesn't eliminate the risk of tapeworms or other illnesses."

However, many dewormers are not effective against tapeworms. Horse owners should look for ingredients like praziquantel--found in broad-spectrum dewormers such as Merial product Zimectrin Gold (ivermectin/praziquantel), which is more than 99% effective against natural tapeworm infections.

"Spring is a great time to consider your parasite control and make sure horses are set up for a healthy year," Cheramie said. "Treating for tapeworm infections, as recommended by your veterinarian, can easily and inexpensively help prevent the potential health concerns that go with tapeworms."

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