Improvement of gastric disease and ridden horse pain ethogram scores with diet adaptation in sport horses

Background: Gastric disease is highly prevalent in sport horses and may lead to poor performance, cause behavioral changes and impact welfare.

Hypothesis: Assess whether diet affects gastric disease and pain expression during riding, and whether it has an impact on physiological and locomotor variables during an exercise test, including jumps.

Animals: Nine healthy show-jumping Warmbloods trained at the same stable.

Methods: Prospective observational cohort study. The horses receiving a pelleted diet, high in sugar and starch (>30%), were examined at T0 and after 12 weeks (T12) of changing to a cooked, muesli-type low-starch (11%) diet. Each time, the horses underwent a standardized exercise test (SET) and a ridden pain score (Ridden Horse Pain Ethogram [RHpE]) was calculated by 2 blinded observers. The next day, horses underwent gastroscopy and gastric lesions were scored blindly. Results were analyzed using Wilcoxon and Spearman tests.

Results: After 12 weeks of a low starch diet, the Equine Gastric Disease (EGD; 4 [3-5] at T0 vs 1 [0-1] at T12, P < .01) and RHpE scores (6 [3-13] at T0 vs 3 [0-6] at T12, P < .01) improved significantly. Squamous, glandular, and EGD scores were positively correlated with RHpE scores (respectively, r = .747, P < .01; r = .743, P < .01 and r = .867, P < .01).

Conclusion and clinical importance: Gastric disease and pain scores correlated positively in ridden horses. A low starch diet significantly decreases the severity of gastric disease and associated pain score during riding in horses. Gastric ulcers may be mitigated and the comfort of equines athletes improved by dietary adjustments.