Gastric ulcer syndrome refers to ulceration of the horse’s stomach lining. Several factors, including nutrition, have been shown to increase the risk of ulcers developing, particularly in the nonglandular, or squamous, part of the stomach. (The horse’s stomach is divided into two sections: the upper nonglandular portion and the lower glandular portion. Stomach acid is secreted in the glandular portion, which is coated with a protective mucus and bicarbonate layer. The nonglandular portion has less protection from mucus and bicarbonate, making it more prone to gastric ulcer development.) In horses that are actively exercising and training, the incidence of gastric ulceration has been reported to be up to 90% in some subpopulations. While dietary and management changes are often recommended to help reduce EGUS risk, they’re often suggested in conjunction with or following veterinary pharmaceutical treatment. However, until now there has been little published work to confirm their benefit under such circumstances.
The new research study, “Effect of changing diet on gastric ulceration in exercising horses and ponies following cessation of omeprazole treatment,” was conducted by Nanna Luthersson, DVM, from the private Danish practice Hestedoktoren, and Coby Bolger, DVM, managing director Horse1 Equine Nutrition and Care Center, in Spain. The pair also worked with colleagues from the University of Madrid, in Spain; University of Glasgow, in Scotland; Spillers, in England; and the WALTHAM Equine Studies Group, also in England. The study was presented at the International Equine Colic Research Symposium, which took place July 18-20 in Lexington, Kentucky.
The study evaluated the effect of dietary change in combination with omeprazole treatment and after treatment was discontinued. The 32 horses in this part of the trial had been diagnosed with significant equine squamous gastric disease (ESGD) and were in hard work. For the purpose of more accurate comparisons the horses were paired, according to the severity of their ulcers, workload, management, and original diet.
On a random basis one of each pair was assigned to a specified low-starch, fiber-based diet consisting of their own forage alongside a high-fiber high-energy cube (Spillers HDF Power Cubes) and a high-oil, low-starch, chopped-alfalfa-based feed (Winergy Equilibrium Growth). The other stayed on their original diet. All animals were scoped before, after the recommended course of omeprazole treatment, and six weeks after the omeprazole finished.
The ulcers in horses in the no diet change group improved significantly with omeprazole administration, but when the treatment was stopped many horses’ ulcers regressed. Overall, by the end of the trial, they were not significantly different to when they had started.
However, the horses in the dietary change group overall showed significantly improved ESGD scores, not only following the omeprazole treatment but also after the treatment had stopped. This showed that a diet change helped maintain omeprazole’s beneficial effects even after treatment ended.
“This exciting work confirms what we suspected: that whilst appropriate dietary change can provide additional support to medical treatment for EGUS most importantly it can help maintain better gastric health post medical treatment,” said Clare Barfoot, RNutr, research and development manager at Spillers.
The study achieved an award in 2016 for research in horse welfare from the Fundación para la Promoción del Deporte Ecuestre, Spain.