Tapeworm Treatment for Horses

Tapeworms live at the junction of the small and large intestines and occasionally in the stomach of the horse. There are three species of tapeworms, Anoplocephala perfoliata, Anoplocephala magna, and Paranoplocephala mamillana, which infect the horse. Based on blood tests, tapeworms are the cause of more than one out of five cases of spasmodic colic and three out of four cases of ileocecal impactions--blockage at the end of the small intestine.

  1. Life Cycle

    • The adult tapeworms sheds segments of its body, which contain eggs and are passed out in feces. These segments soon break down and release the eggs on to the pasture where they are consumed by small mites called orbital mites, which live in the dirt. Here they develop for about four months; they find their way inside the horse when the mites are taken in with a mouthful of grass. Once inside the large and small intestine, the tapeworms can grow up to 12 inches long. It takes four to eight months to complete the life cycle, according to the University of Kentucky.

    Symptoms

    • If large infestations of tapeworms exist, acute attacks of spasmodic colic occur due to damage and interference with the efficient working of the ileocaecal valve. As the damage becomes chronic, unthriftiness, diarrhea and weight loss are also seen in the horse.

    Diagnosis

    • Detection of tapeworms is conclusive through a blood test that detects an antigen, which is specific for the tapeworm protein. At times, eggs can be seen in the manure of the infected horse. Egg cases look like rice kernels and are able to move.

    Treatment

    • According to Dr. Kevin Hankins, DVM at Fort Dodge Animal Health, the FDA has approved praziquantel as an effective treatment for tapeworms. It is a combination of an anthelmintic product and avermectins, such as ivermectin or moxidectin. This is the first successful option in killing and expelling tapeworms in horses, along with destroying pinworms, bots, strangles and ascarids, according to the Horse Channel.

    Prevention

    • Preventative treatment for tapeworms includes a twice-yearly dose of Strongid-P. The first dose should be given six to eight weeks after the horse is turned out in the pasture in the spring, and the second in the fall.