Should you feed your horse hay before riding? Offering appropriate forage before exercise may help support your horse’s natural gastric defenses, but new research is investigating how effectively hay and chaff reduce acid exposure while horses are working.In this video, we explain how exercise may cause acidic stomach fluid to move upward toward the sensitive squamous region of a horse’s stomach—a process commonly called acid splash. We also discuss why horses exercised after prolonged periods without forage may face an increased risk of equine squamous gastric disease.Researchers at the University of Queensland are conducting a two-year study funded by the Grayson-Jockey Club Research Foundation. Using wireless pH capsules attached to the stomach lining, the researchers will compare gastric acidity when horses exercise after receiving hay, chopped forage known as chaff, or no feed.The study may help determine whether hay and chaff provide the same protection during exercise. However, the final results are not yet available, and feeding forage before riding cannot guarantee that a horse will remain ulcer-free.We also explain the difference between equine squamous gastric disease and equine glandular gastric disease, why saliva and forage may help buffer stomach acid, and why large grain meals should not be confused with appropriate forage before exercise.Always discuss your horse’s feeding program, performance changes, or possible gastric-ulcer symptoms with your veterinarian or qualified equine nutritionist. This video is provided for educational purposes and is not veterinary advice.Chapters: