Stress explored as factor in equine stomach ulcers

May 29, 2009


Many Danish horses have stomach ulcers. Whether the ulcers mean that the horses are stressed or not is something scientists have now started investigating. © Jens Malmkvist

Researchers will explore what part stress plays in stomach ulcers in horses.

Stomach ulcers are common in horses and scientists are increasing their focus on the problem, including the factors contributing to their development.

Scientists from the Agricultural Sciences faculty at Aarhus University in Denmark are investigating the possible connection between stomach ulcers and stress in horses. They hope to answer questions over the importance of the ulcers, the contribution of stress - if any - to the condition and whether horses with stomach ulcers have a greater tendency to crib-bite or have other types of abnormal behaviour?

"Even though there are a lot of indications that ulcers are common in horses, we don't know how important they are for the horses' level of stress and reactivity despite the fact that it could impact on their welfare and their daily use," says the leader of the newly started project senior scientist, Jens Malmkvist.

Some international studies have found surprisingly high frequencies of damage to the stomach lining of horses - up to 93 per cent in horses that were studied when they were in training. In Denmark the latest figures show that over half of the horses have ulcers to a smaller or larger degree.

In the latest project, the scientists will study three aspects of stomach ulcers:

About 100 horses will be investigated to find out if they have ulcers and, if that is the case, the seriousness of the the ulcers.

From this group of horses the scientists will establish two smaller study groups. The control group will consist of 30 horses with no or little damage to the stomach lining, while 30 horses with serious damages to the stomach lining will comprise the stomach ulcer group.

The horses' behaviour and level of stress will be measured in different situations. The scientists will systematically register the horses' reactions and behaviour in feeding situations, in the horses' daily lives at home in their own stalls, and in situations that elicit fear in the horses.

The work is supported by the Horse Levy Fund and is being carried out in collaboration with Danish horse veterinarians and the University of Veterinary Medicine in Vienna.

"The project will contribute to our understanding of what importance stomach ulcers has for horses, which can also impact the daily use and handling of horses," says Malmkvist.