What is gastric ulceration and why does it happen?
Equine Gastric Ulceration Syndrome (EGUS) is a common disease affecting the equine stomach. The horse’s stomach is divided into two very distinct areas, the squamous and glandular regions. These are separated by a sharp demarcation called the margo plicatus. Horses can develop ulcers in both parts of the stomach and horses may be diagnosed with ulcers affecting one or both regions.
It is often perceived as a disease mainly affecting performance and race horses. With studies showing that up to 90% of race horses in training and 60% of performance horses having EGUS. However up to 50% of leisure horses, including ponies which live out 24/7 and 50% of foals in the UK may also suffer from EGUS.
Horses are designed to trickle feed, which means they forage and slowly graze for up to 20 hours a day. This constant grazing allows a continuous source of saliva and fibre within the stomach which is broken down by acidic gastric juice.
Squamous gastric diasease is primarily associated with acid exposure to this portion of the stomach from intensive management. Glandualr gastric disease is due to a breakdown in the stomachs normal protective mechanisms leading to acid exposure.
What are risk factors for gastric ulceration?
There are many risk factors for gastric ulceration including breed and management. Some risk factors are listed below:
- Low forage/roughage and high concentrate diets
- Intense/increased levels of exercise – intense exercise can be classified as anything above walking!
- Prolonged periods of starvation/lack of access to forage throughout the day
- Lack of access to fresh water
- Increased stress levels that may be secondary to regular transport, change in management or housing, competition, separation from companions etc.
- Concurrent disease or lameness
- Weaning is a risk factor for both mares and foals.
What are symptoms of gastric ulceration?
Symptoms can be very varied between horses and the severity of the lesions does not always correlate with the severity of the symptoms. The most common clinical signs are:
- Weight loss
- Slow eating/variable appetite
- Discomfort on girth tightening
- Resistance to leg aids/grooming
- Behavioural changes
- Colic symptoms
- Poor performance – refusing to go forward, bucking, rearing
- Poor coat condition
How are ulcers diagnosed?
The only way to definitively diagnose the presence, type and severity of gastric ulcers is by gastroscopic examination. Gastroscopy involves passing a narrow video-endoscope (fibre-optic camera) into the stomach, under sedation, to visualise the stomach lining and assess any ulcers that may, or may not, be present. This procedure is minimally invasive and well tolerated by most horses/ ponies.
How are ulcers treated?
Treatment for EGUS is dependent on the type and severity. Medications often prescribed include omeprazole, sucralfate and misoprostol. Ulcers are curable, but may require long-term treatment and do require long-term management!
Feeding & management for affected or at-risk horses
Feeding management is aimed at optimising gastro-intestinal function and minimising the deleterious effects of excess acid and its production. A suggested feeding protocol for a horse with, or at risk of, gastric ulceration would include:
- Increasing pasture turnout with concurrent access to roughage/forage
- Providing ad lib, good quality hay or haylage, and avoiding straw as the only forage available. In horses which are prone to putting on weight easily, it is still essential that feeding management is combined with weight management.
- Concentrates should be fed in small quantities and increase number of feeds rather than increasing size of feed where possible (less than 0.5kgs per 100kgs bodyweight per feed)
- Oil supplementation (e.g. 45-100mls of corn, rapeseed or vegetable oil, twice daily in feed), which coats the glandular portion of the stomach, providing additional protection.
- Minimising feed deprivation, especially no longer than 6 hour intervals with no access to forage (this includes during transport and while competing etc.)
- Exercising your horses in the afternoon or giving hay 30 minutes before exercise, to ensure that they have a fibre buffer preventing acid splash back – this will not increase the likelihood of colic!
- Free access to fresh, clean water at all times, including when turned out.