Horses secrete stomach acid 24 hours a day. When horses eat, they produce saliva. Saliva contains sodium bicarbonate and is therefore a neutralizer for the stomach acid. The food itself also helps to neutralize the stomach acid and to form a protective barrier against the stomach acid. In nature, horses eat small amounts for about 16 hours a day. This almost always neutralizes the stomach acid. If we feed our horses large portions a limited numbers of times a day, there can be long periods of inactivity where the stomach acid is not being neutralized. 

The stomach only secretes acid in the lower glandular part. Glandular cells can also be found here that secrete substances. The upper part of the stomach remains mostly empty and does not secrete any acid. It also has no protective membrane against the acid. Having a layer on top of the stomach acid helps to protect the upper part of the stomach against contact with the stomach acid. If there is a long time between feedings, the protective layer begins to degenerate. Food stays in the stomach for about 6 hours. If the horse would start to move, the contents of the stomach would move with it. This increases the chance that acid will come into contact with the upper (unprotected) part of the stomach. This can cause stomach ulcers. The good news is that there are some quick and easy things you can do to reduce this risk. 

1. The first and most obvious advice is to feed roughage before training or riding your horse. 
2. If you don’t have time to wait for the horse to eat their meal, no problem. You can give some hay as you are grooming your horse and getting ready to ride. Even a little bit promotes saliva production and forms a protective layer. 
3. If your barn doesn’t allow you to take some hay, there are chopped roughage mixes you could feed. Some are even created especially for reducing the risk of ulcers. Alfalfa has a better buffering capacity than grass hay, so if given the choice, feeding a small amount of alfalfa or chopped alfalfa would be ideal in this situation. 
4. Another option besides feeding hay before riding ride is to feed a good stomach buffer when you arrive at the stable. The idea is that if you make the acid less acidic, it won’t affect the stomach lining as much. Research has shown that calcium buffers the stomach quite quickly. It can be found in products designed specifically for this purpose and other forms of commercial feed. 
5. There are also supplements that coat the lining of the stomach to help protect it from the acid. However, they may not work fast enough for pre-ride use. Always ask the manufacturer about this. 

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