Antioxidants And Gastric Ulcers

Equine Gastric Ulcer Syndrome (EGUS) is a general term used to describe ulcers in the stomach. The disease is now further categorised where ulcers are specifically present in the squamous region (EGSD) or the glandular region (EGGD). There are many risk factors and management strategies offered regarding the disease, and more recent research has suggested that antioxidant support may be of benefit.

What is an antioxidant?

Oxygen is vital for survival for almost all living creatures, however some oxygen molecules form free radicals that react and damage cells at molecular levels. Antioxidants are compounds that scavenge and defend the cells against free radicals, however oxidative stress can occur when free radicals outweigh the natural antioxidant defence system. This can cause damage to organs and tissues, increasing the risk of disease, poor performance and poor recovery.

Antioxidants and Gastric Ulcers

Research into the detection of gastric ulcers in horses has more recently looked at the use of oxidative markers in saliva (Contreras-Aguilar M.D et al, 2022). The research found that horses suffering with EGGD had increased antioxidant biomarkers, suggesting that the immune system may be linked to the development of the disease. Further research by López-Martínez et al (2023) has also looked at changes in proteins found in saliva in horses who have been diagnosed with EGUS. The protein albumin was found to be reduced in horses with EGUS, and the theory stated was that low albumin values could increase oxidative stress responses and in turn produce ulcerative lesions in gastric mucosa. Finally, previous research by Shawaf et al (2019) also looked at markers in blood samples. Whilst clear markers were not found, it was found that pro-inflammatory cytokines that contribute to tissue damage was increased in horses with EGUS. Compounds believed to ‘protect,’ the gastric mucosa by providing defence mechanisms against free radicals were also reduced, suggesting that horses with EGUS do experience greater oxidative stress.

Based on this preliminary research, offering additional antioxidants into the ration may be of benefit. Vitamin E is a powerful antioxidant that protects the horse from free radical damage. It is considered ''the king'' of antioxidants as it can move between cell membranes and stabilise body systems (such as the immune system). The best source of vitamin E for the horse is fresh, green grass so over the winter months or for horses with restricted access to grazing, the use of a Vitamin E supplement can be a useful addition to your horses feed.