A recent (2019) study conducted in Finland examined the association between the presence and size of intestinal sand accumulations and owner-reported clinical signs, management, and feeding practices, as well as behavioral patterns in horses with radiographic diagnosis of sand accumulation.

Approx 447 owners of the horses filled in an online questionnaire. The size of the sand accumulation detected in the radiographs was not significantly associated with the age, body condition score, sex, or use of the horses. Horses reported to have expressed colic had significantly larger sand accumulations than those without this sign, and a similar association was detected in horses with poor performance.

Larger sand accumulations were detected in greedy horses that eat all their roughage, whereas dominant position in group hierarchy was associated with less sand.

In this study, diarrhea was a more common sign than colic also in the group of horses with large sand accumulations. However, diarrhea alone was not significantly associated with the size of sand accumulation.

Problems associated with large colon sand accumulation seemed to intensify during autumn and early winter. The time lag between gaining a sand accumulation and showing clinical signs is unknown, and may depend on a horse’s pain tolerance.

The results suggest that some behavioral characteristics can be linked to intestinal sand accumulation. Greedy horses that eat all their roughage had larger sand accumulations. They also however, demonstrate that dominant behavior was associated with smaller sand accumulation. This might be due to dominant horses getting the best or the most hay.

It remains unclear why some horses had no sand accumulation despite being observed to eat sand. The mechanisms of accumulation are obscure, but when accumulation occurs, the weight of the sand might hinder the physiological movements of the colon. One theory to explain the original accumulation might be an initial decline of intestinal motility. Horses with sand colic often present with colon impaction both of these conditions can be related to insufficient intestinal motility. Therefore, individual variation in gut motility and associated physiology may affect the accumulation of sand and the rate of its removal.

This study suggests that the possibility of abdominal sand accumulation should be kept in mind as one of the differentials in horses with clinical signs such as colic, poor performance, diarrhea, and sensitivity to touch of the abdominal wall.

DIAGNOSIS

Radiographic examination is currently the most reliable and commonly used diagnostic method for sand accumulation. It also allows response to therapy to evaluated (ie. before and after xrays).