It is estimated that 90% of racehorses, 50-60% of competition horses and up to 50% of leisure horses have gastric ulcers. Although veterinary treatment may be required initially, it may only be effective for a short time. Research carried out in collaboration with SPILLERS is the first to provide scientific evidence that changes in diet can help to prevent the recurrence of gastric ulcers after veterinary treatment has stopped.


The horses

Fifty eight race and competition horses were divided into pairs according to their workload, management and gastric ulcer score (graded 0-4).

Scoping for gastric ulcers

The trial (10 weeks)

*All horses with grade 3 and 4 ulcers were treated with the recommended course of omeprazole (weeks 1-4).

*One horse from each pair had their normal hard feed replaced with a 50:50 ration of SPILLERS HDF Power Cubes and SPILLERS Ulca Fibre (divided between 3 meals) for the full 10 week trial.

*All horses were scoped at the start of the trial, immediately after omeprazole treatment and 6 weeks after treatment had stopped.

The results: grade 2 ulcers

The trial diet had no effect on grade 2 ulcers. At the end of the study, gastric ulcer scores in the horses that were fed the trial diet were not significantly better or worse than in horses that that were not fed the trial diet.


The results: grade 3 and grade 4 ulcers

*All but one horse improved as a result of omeprazole treatment.

*Overall, gastric ulcer scores in horses that were fed the trial diet remained improved 6 weeks after treatment had stopped.

*Six weeks after treatment had stopped, gastric ulcers scores had worsened in the majority of horses that were not fed the trial diet so that overall, there was no difference between pre and post treatment scores.

Equine Gastric Ulcers

What does this mean?

This is the first scientific study to show that diet can help to reduce the risk of gastric ulcers recurring after treatment, even if other changes in management are not possible. As this study only evaluated changes in ‘hard feed’, it is possible that greater improvements could have been achieved if changes if forage were also made. There was also no apparent long term benefit of omeprazole treatment alone, highlighting the importance of other strategies in the long term management of horses prone to gastric ulcers.


For more advice on feeding horses prone to gastric ulcers contact the SPILLERS Care-Line



Luthersson N et al., Effect of Changing Diet on Gastric Ulceration in Exercising Horses and Ponies After Cessation of Omeprazole Treatment, Journal of Equine Veterinary Science,