Equine Gastric Ulcer Syndrome   

Causes of EGUS?

The syndrome is not yet fully understood and sometimes the triggering factors remain unknown.

In adult horses, the following may cause EGUS: 

• Restricted feed intake, especially roughage

• Periods of starvation

• High grain diets

• Ridden exercise

• Stress

• Types of medication

• Causes may also be unknown

In foals, causes of gastric ulceration can include:

• Physiological stress

• Other bowel diseases e.g. diarrhoea

• Infrequent nursing or feeding

• Other illnesses e.g. infections such as pneumonia

• Causes can also remain unknown

Anatomy of the equine stomach

Signs of EGUS

Adult Horses

Clinical signs of stomach ulceration can often be mistaken for other conditions or behavioural problems. Signs may include:

• Poor performance
• Dull appearance
• Picky appetite
• Grumpy temperament
• Resistance to riding aids
• Resistance to girthing

Foals

Gastric ulceration is common in foals and they can develop from two days of age. Ulcers can often occur secondary to other diseases, particularly bowel problems such as diarrhoea and obstructive colic.

Clinical signs may include:

• Salivation
• Teeth grinding
• Restlessness
• Diarrhoea
• Signs of colic, including rolling
• Poor appetite
• Intermittent nursing

What to do if you think your horse is suffering from ulcers: 

1. Contact your vet to arrange a gastroscopy procedure and confirm diagnosis. 

2. Administer treatment as advised by your vet 

3. Consider management changes to help aid the healing of ulcers and prevent recurrence 

4. Discuss a preventative plan with your vet if you anticipate stressful situations, e.g. travel, change of companion, etc. 

Diagnosis - Gastroscopy

If gastric ulcers are suspected, the only way to confirm the diagnosis is for a vet to perform a gastroscopy. The gastroscopy involves a three-metre endoscopic video camera being passed into the horse's nose, down the oesophagus and into the stomach. This is usually carried out under light sedation and causes minimal distress to the horse. 

During the gastroscopy, the vet will score the squamous ulcers for severity, from 0-4, 4 being the most severe. This allows the vet to benchmark the horse's healing progress. 

Treatment

Oral medication is recommended if gastric ulcers are identified in adult horses, with the most common medication being omeprazole. Treatment may last several weeks to months depending on response to medication. The vet will then monitor the treatment progress and also suggest management and feeding changes.

In foals, treatment is recommended from four weeks of age, depending on the clinical severity. 

Omeprazole

Omeprazole is the mainstay licensed treatment for gastric ulcers and it works by blocking acid release from the proton pumps within the lining of the stomach. It is good to note that omeprazole does not affect a horse's ability to digest food.

Feeding and management changes can aid ulcer recovery and help prevent recurrence.

Changing your management may reduce the risk of ulceration in your horse. As stress and diet are known factors which predispose horses to disease. 

Things you can do to reduce the risk of ulceration in your horse:

General nutritional management:

• Feed two litres of forage (hay/chaff) 30 minutes prior to exercise - this will help to create a 'fibre mat', which will help to prevent the splashing of acid within the stomach 

• Allow your horse access to grazing, ideally with at least one other companion

• When your horse is stabled, offer hay ad libitum

• Double hay nets or hay nets with smaller holes can increase the duration of forage activity. Two separate hay nets are also beneficial in increasing 'stable forage time'

• Minimise the amount of grain and concentrate feeds 

• Ensure your horse has constant access to clean water

Other management changes: 

• Limit stressful activity or training 

• Allow your horse to have 2 days of rest a week 

• Minimise changes to routine such as companions or human carers