New research on gastric ulcers [H&H VIP]

How does hay intake affect gastric ulcer risk? Peter Green MRCVS looks at the latest research

Gastric ulcers have become a hot topic in recent years.

Many stabled horses seem to suffer, especially if they are stressed, but ulcers are much less common in horses at grass. There appears to be a link between the intermittent, twice or three times daily feeding of stabled horses and the high incidence of ulcers, compared with the continual “trickle feeding” of horses at pasture.

The increase in stomach acid that occurs during periods without food is a cause. If horses are deprived of food, the risk of ulcers is increased, but there is also a problem of equine obesity — restricting food is sometimes a necessary part of management.

If you put your horse on weight-loss diet, are you increasing the risk of gastric ulceration?

Vets in the USA investigated this by placing acid-measuring probes in the stomachs of 8 horses before feeding them hay, either ad lib or in a restricted way through a small-mesh hay bag. All the horses had hay available all the time.

In common with other studies, the vets found that horses ate more during the day than at night. There was no difference between the 2 groups in the total amount of time spent eating, but the horses eating from small-mesh bags consumed 20% less than those given a big pile of hay.

The gastric acid measurements were only very rough, because the vets could not be sure that the probes were all in exactly the same place. It looked pretty certain, however, that the horses eating hay through small-mesh bags suffered no increase in acidity. This suggests that we can diet our horses using small-mesh feeders without risking ulcers.