Sand colic due to an accumulation of sand in the intestines accounts for up to 30% of all colics, often causing weight loss and chronic diarrhea. Psyllium has often been recommended as a laxative for clearing sand out of the intestines, although previous research results have been mixed as to its effectiveness. Allen Landes, DVM, of Equine Medical Service in Fort Collins, Colo., discussed the efficacy of a commercial psyllium/probiotic/prebiotic product (Assure and Assure Plus) on fecal sand clearance at the 2007 American Association of Equine Practitioners Convention, held Dec. 1-5 in Orlando, Fla.

“There are three risk factors leading to sand accumulation: Soil type, pasture quality, and feeding practice,” Landes noted. “As clinicians, we can only modify one of these (feeding practice). Our sand content at this study location was about 28%, but many nearby areas are more than 60% sand. Owners can visit to get more information on the sand content of their local soils and see if they have a sand problem.”

Eight clinically healthy horses were kept on pasture and/or in stalls during the study, and they were supplemented with hay to maintain body weight. Their feces were screened for sand for seven days before any treatment. For 35 days afterward, they received 30 g of Assure (probiotic/prebiotic mix intended to improve the health of gut microflora) followed by 226 g of Assure Plus (probiotic/prebiotic with psyllium) per 454 kg (1,000 pounds) of body weight 12-15 hours later, according to the manufacturer’s directions. No horses developed colic during the study.

Fecal sand output significantly increased (nearly doubling) by Day 4 of treatment and remained elevated through Day 31, reported Landes.

“These results suggest that this product may be an effective prophylactic treatment for sand entero