Colic: In-Depth Discussion by Vets at AAEP

Almost all horses with colic can be saved if the problem is recognized quickly and treatment is instituted rapidly, said Anthony Blikslager, DVM, PhD, Dipl. ACVS, of North Carolina State University, during the "In-Depth: Colic" portion of the 2009 American Association of Equine Practitioners (AAEP) Convention's scientific program. The convention was held Dec. 5-9 in Las Vegas, Nev. Horses with early signs of colic, he reported, tend to stand toward the back of the stall and lose interest in observing other horses and people in the barn. Not finishing a meal is another potential sign of trouble.

Pre-planning for emergencies is important to facilitate treatment of a colicking horse, according to Blikslager. He recommended encouraging owners, trainers, and farm managers to have a plan for transporting a seriously ill horse to avoid the delay that can occur when trying to find an available truck and trailer.


Dr. Blikslager talks about colic in horses.
Play video

Blikslager discussed colic involving the small intestine specifically, and he said a key to preventing it is reducing its two major risk factors: tapeworm infection and feeding horses suboptimal quality coastal Bermuda hay (applicable to those owners using Bermuda hay in the southeastern United States).

Tapeworm infection is very difficult to detect using routine fecal flotations, but fortunately you can use an enzyme-linked immunosorbent assay (ELISA) test developed in England. Pyrantel-containing anthelmintics offer some protection against tapeworms, but praziquantel is more effective. The latter can be found in combination products to be used once or twice a year.

When you feed a horse Bermuda hay, Blikslager said, feed a high-quality product and acclimate the animal to it slowly.

Alison J. Morton, DVM, MSpVM, Dipl. ACVS, of the University of Florida, said advances in the management of colic involving the large intestine include the availability of the antispasmodic medication N-butylscopolammonium bromide, the diagnostic use of ultrasonagraphy, and the use of enteral fluid therapies.

Enterolith impaction, which is a common cause of colic in California and other regions of the country, is associated with long-term ingestion of large quantities of an alkalinizing feed rich in protein, phosphorous, and magnesium, such as alfalfa, Morton said. Another risk factor is drinking water with high magnesium content.

Arabians and Arabian crosses, Morgans, American Saddlebreds, donkeys, and Miniature Horses are more susceptible to enterolith formation than other breeds.

Modifications in diet can help prevent enterolith impaction, Morton reported. Alfalfa should not constitute the majority of a horse's roughage intake, and greater than 50% of the roughage should be provided as grass or grass hay. Minimize the use of wheat bran because of its high phosphorous content. In areas with high magnesium content in the water, you should consider an alternate source of water.

If dietary modifications aren't possible, veterinarians have recommended twice daily administration of an acidifying agent, such as one cup of apple cider vinegar. However, the benefits of vinegar haven't been confirmed, Morton said.

Disclaimer: Seek the advice of a qualified veterinarian before proceeding with any diagnosis, treatment, or therapy.