Equine Gastric Ulcer Syndrome (EGUS) is a painful condition that describes erosions and -lesions in the lining of the stomach and proximal gut of horses. Two distinct diseases have been identified which can affect different areas of the stomach; Equine Squamous Gastric Disease (ESGD), and Equine Glandular Gastric Disease (EGGD), with less understood about the latter.
What are the predisposing factors?
Foals and performance horses are at greatest risk of developing gastric ulcers, but they can be found in horses of any age and in any level of work. Predisposing factors include:
- Periods of high stress, such as transport, a sudden change in management, or illness
- A diet that is too high in concentrates and/or too low in forage
- Exercising on an empty stomach
- Intermittent feeding – horses should be fed little and often, rather than fewer larger meals
- Excessive use of non-steroidal drugs (e.g. bute)
What are the clinical signs?
- Poor performance e.g. reluctant to go forward off the leg, poor behaviour under saddle
- Mild colic
- Poor appetite
- Girthy, doesn’t like being brushed or touched over their abdomen
- Mild weight loss
Clinical signs of gastric ulcers in horses can be vague and non-specific, whilst some horses do not show any signs at all. This makes it tricky to diagnose EGUS from clinical signs alon
How do you diagnose EGUS?
As the symptoms of gastric ulcers can be difficult to distinguish from other issues or diseases, or are often absent, the only way to diagnose this condition accurately is via a gastroscopic exam. This involves passing a camera (gastroscope) up the horse’s nose and into its stomach to visualise the lining and identify whether any ulcers may be present. The horse must be starved for 12 hours beforehand – ideally overnight before they are scoped in the morning – so that they have an empty stomach. This allows any ulcers present to be seen clearly, and graded based on their severity.
Squamous ulcers (EGSD) (pictured) are found on the pale pink squamous area at the top of the stomach near the entrance from the oesophagus. This area does not have protection against stomach acid, hence it is prone to ulcers from acid injury. Ulcers are graded 1-4, based on severity.
Glandular ulcers (EGGD) are found near the exit of the stomach into the small intestine. This area is a much darker pink and produces the stomach acid needed for digestion. The mechanism by which ulcers appear in this area is less well understood, as it has a protective mucous layer to stop acid injury. These ulcers are not graded, but rather described based on factors such as size, location and whether or not they are actively bleeding.
Can ulcers be treated? What are the options?
- Omeprazole injections – omeprazole has been shown to treat gastric ulcers when given by intramuscular injection. We usually recommend a once weekly treatment for 4 weeks followed by a re-scope to see whether further treatment is required.
- Sucralfate powder – Sucralfate is given orally and binds to ulcers in the glandular region of the stomach. This can be used alongside omeprazole if necessary.
- Esomeprazole – this is a relatively new drug but it is proving efficacious in treating equine gastric ulcers.
Management practices can also make a considerable difference to ulcer healing, such as plenty of turnout, feeding little and often, and providing plenty of forage in your horse’s diet. We recommend that you feed a small scoop of chaff just before exercise to create a fibre matt on top of the stomach acid. This prevents acid splashing onto the squamous portion of the stomach. Exercise intensity should be reduced to allow time for ulcers to heal and try to avoid stressful situations where possible, as this could exacerbate the problem.
For competition horses that require more energy, consider swapping cereal-based concentrates for more digestible fibre sources like alfalfa with added oil. Research has shown that alfalfa is a better buffer to acidity than other fibre sources due to its protein and calcium content.
If you think your horse may need investigating for ulcers, please contact us to make an appointment with one of our vets.