Horses living near a coast or in the warm desert sun might seem to have a luxurious life, but many equines in these areas are threatened by abdominal sand on a daily basis. These occurrences were a problem for a group of veterinarians from Arizona Equine Medical and Surgical Center (AEMSC). Those practitioners studied 24 horses suffering from intestinal sand between 1991 and 1993. This previously unpublished study reported that psyllium (horse-strength Metamucil) could be an effective means of eliminating sand from the gut of a horse. This contradicts a study that said psyllium is ineffective for helping a research pony rid sand placed in his cecum.


Mark Revenaugh, DVM, was a collaborator in the Arizona study. He now works with B.W. Furlong & Associates veterinary firm in New Jersey. Revenaugh explained that many horses ingest sand on a daily basis in the Phoenix Valley, and he recalled cases where up to 50-60 pounds of sand were found in the right dorsal colon. “(In surgery) you had to be careful that you didn’t tear the colon–it was like picking up a bag of concrete,” he said.

Veterinarians are not sure why the horses ingested the sand, but Revenaugh said there were no indications that horses had a mineral imbalance that might have caused the consumption. In fact, questionnaires returned by the horse owners did not verify any significant management issues that would contribute to such behavior except that they were fed at ground level.

After seeing so many horses suffering with a virtual beach in their GI tract, Revenaugh, Gayle Leith, DVM, MS, ABVP, and Kent Allen, DVM, (now of Virginia Equine in Middleburg, Va.), all of whom were practicing at AEMSC at the time, began a study that involved 24 horses suspected of suffering from intestinal sand build-up. Symptoms were abdominal discomfort (38% of the admitted horses), weight loss (38%), or diarrhea (24%), all with sand in the manure and characteris