Equine Gastric Ulcer Syndrome (EGUS): painful, potentially serious, surprisingly common and affecting horses of all ages, breeds and types. In 2009, a Danish study of 201 leisure and sport horses found that an incredible 83% had gastric ulcers. So, what are they, how do you spot if your horse has one and how are they treated?
The horse's stomach
Horses are known as "trickle feeders". Their digestive system has evolved to process forage in small, frequent quantities. The stomach is relatively small – about the size of a rugby ball – and rests halfway along the left-hand side of the body, just behind the scapula. The upper part of the stomach is called the squamous mucosa and is lined with pale tissue similar to that found inside our mouth. The lower stomach is called the glandular mucosa. Dark pink in colour, it contains acid secreting glands and a protective layer of mucous. A line called the margo plicatus separates the upper and lower areas of the stomach.
Why do horses get gastric ulcers?
Ulcers can occur anywhere in the stomach and are formed as a result of acid exposure. If a horse has eaten nothing prior to exercise, stomach acid is unrestricted and can splash onto the unprotected tissue in the upper part of the stomach. The lower part of the stomach can also be affected despite its built-in protective lining. It is thought that something causes the mucosal barrier to become weakened allowing ingress of stomach acid.
EGUS can affect horses of any age, breed and type. Research has shown that horses on high-concentrate/low-forage diets, long periods with little or no intake of food, very intense exercise and stress from travelling etc can all play a part. It has been shown that the 20 to 80 litres of saliva a horse produces during a normal trickle feeding day effectively neutralises stomach acid and therefore helps to promote a healthy gastric environment. Restricting a horse's access to regular small amounts of forage is clearly not ideal. It is also vital that the horse has access to fresh, clean water at all times. Water deprivation is a significant ulcer risk.
Signs of EGUS
Symptoms vary greatly from horse to horse, some exhibiting no symptoms at all. Common signs include:
Weight loss and poor appetite Loss of condition and dull coat Mild, recurrent colic Stretching to urinate Reduced or uncharacteristically poor ridden performance Behavioural changes Discomfort on having the girth tightened Extra sensitivity during grooming
If ulcers are suspected, your vet will carry out a non-surgical endoscopy. This is the only way of diagnosing ulcers. The horse is sedated and a video gastroscope is passed down the oesophagus and into the stomach. Areas of concern can then be photographed. The procedure usually takes around five minutes.
Ulcers can range from tiny areas of inflammation to deep craters containing dead or dying tissue. A scoring system from 0 to 4 is used as a means of grading the severity of ulcers.
Treatment will depend upon the type, appearance and severity of the ulcers. The most effective drug for treating ulcers is omeprazole which inhibits the secretion of gastric acid. Rather than curing the ulcers the drug makes the horse more comfortable and allows healing. In some cases, antepsin tablets which help form a protective barrier over ulcers may be prescribed. In severe cases, your vet may prescribe a short course of antibiotics.
It is important during the horse's recovery to manage his feeding carefully. Plenty of good quality forage available ad-lib is essential to increase saliva production and the addition of alfalfa is helpful because it has an antacid effect. Corn and rapeseed oils help to reduce acid production and increase the production of protective elements which helps existing ulcers to heal. Ongoing management of the horse and in some cases a total change of routine will be essential in healing existing ulcers and preventing a recurrence of the condition. Recovery should take place in about six months.
Protecting your horse
You can help to protect your horse from EGUS through careful feeding and management. Feed plenty of fibre and ensure that he has access to ad-lib hay or haylage if he's stabled or his grazing is poor. Hard feed rations should be split into several small feeds to be given throughout the day. Make sure he has a couple of handfuls of alfalfa cubes or similar before he's ridden to help coat his stomach walls and reduce acid movement during exercise. Always provide him with plenty of fresh water.
Reduce stress by ensuring that your horse spends as much time as possible grazing at liberty in the field. If he must remain stabled for long periods, allow him to have contact with other horses or install stable mirrors. If he becomes stressed when travelling try using a calmer supplement, travel him in company or install mirrors in the horsebox or trailer.
Disclaimer: Of Horse! and sponsors do not endorse nor validate the accuracy of a blog post. Each article is the opinion of the blogger.