Sand Enteropathy in Horses: Sand Colic, Diarrhea, and Prevention

Sand enteropathy is intestinal disease caused by a horse swallowing enough sand or dirt that it builds up in the large intestine. That material can irritate the intestinal lining, interfere with normal movement of feed and fluid, and in some horses lead to partial blockage. The result may be chronic loose manure, weight loss, poor performance, or episodes of colic.

Many horses pick up small amounts of sand without becoming sick. Trouble starts when exposure is frequent or the amount is large enough that the gut cannot clear it well. Horses kept on sandy pasture, dry lots, or pens where hay and grain are fed directly on the ground are at higher risk.

Signs can be subtle at first. Some horses have mild, recurring belly pain or manure that stays soft for days to weeks. Others develop a more urgent sand colic with decreased manure output, pawing, rolling, or a painful abdomen. Because these signs overlap with other digestive problems, your vet is the right person to sort out what is going on.

The underlying cause is repeated ingestion of sand or dirt. Horses may accidentally eat it while grazing sparse pasture, cleaning up hay from bare ground, or eating grain placed directly on sandy soil. Foals and some adult horses may also develop a habit of eating dirt, which increases the amount entering the gut.

Environment matters a lot. Dry conditions, overgrazed paddocks, and sandy turnout areas raise risk because there is less grass cover and more exposed soil. When multiple horses in the same setting start showing loose manure or mild colic, your vet may consider sand accumulation high on the list.

Not every exposed horse gets sick. Risk is influenced by how much sand is swallowed, how long exposure continues, the horse's feeding setup, and whether enough forage is available. Horses that spend long periods searching for small bits of feed on the ground may take in more sand than pet parents realize.

Your vet starts with the history and physical exam. Important clues include living in a sandy environment, being fed on the ground, chronic loose manure, weight loss, or repeated mild colic. On exam, your vet may hear characteristic ventral abdominal sounds sometimes called sand sounds, although these are not present in every case.

Diagnosis often combines several pieces of information. Your vet may check manure for visible sand, perform a rectal exam when appropriate, and recommend imaging. Abdominal radiographs can show sand accumulation in the large colon, and ultrasonography may also help in some horses.

Because diarrhea and colic have many causes, your vet may also look for other problems such as parasites, dietary causes, infectious disease, or other forms of intestinal obstruction. That broader workup matters because a horse can have sand accumulation along with another digestive issue.

If your horse is painful, dehydrated, or producing very little manure, your vet may recommend urgent treatment while diagnostics are underway. In those cases, stabilizing the horse comes first.

Prevention starts with reducing how much sand your horse can swallow. Feed hay and grain in tubs, feeders, hay nets, or on rubber mats rather than directly on sandy ground. If pasture is sparse, offer enough forage so your horse is not constantly nibbling close to the soil surface.

Management changes matter more than supplements alone. Improving pasture cover, rotating turnout, and avoiding bare sandy feeding areas can lower risk for the whole barn. Horses that have a habit of eating dirt may need closer supervision and a more structured feeding setup.

In regions where sand problems are common, your vet may recommend preventive psyllium programs. Merck notes that monthly use for about 1 week has been used in higher-risk areas, but the right schedule depends on your horse, diet, and environment. It is best to make that plan with your vet rather than guessing.

If your horse has had sand colic before, keep a lower threshold for calling your vet when manure softens or mild colic returns. Early action is often easier, safer, and less disruptive than waiting for a larger impaction.