The symptoms of ulcers and the symptoms of being Grass Affected can be confusingly similar so therefore it is best not to leap to the conclusion that your horse has ulcers without considering other causes as well.
Most common are gastric or stomach ulcers. The reason is that horses have a smaller stomach than other animals. This is why they cannot handle large amounts of food. Instead they are meant to graze for most of the day so the stomach has a continuous trickle of fibrous material going through.
Horses require a steady flow of acid for digestion so the horse's stomach produces large amounts of acidic fluid 24 hours a day, 7 days a week, even in those periods of the day when they are not eating. The act of chewing produces a continuous supply of saliva which keeps the stomach acid at exactly the right pH and prevents it from becoming more and more acidic.
Any time there are forced spells without access to forage as when horses are fed ‘meals’ without access to roughage in between, the lack of chewing means the stomach acid becomes too acidic as no saliva is produced to prevent this happening. According to the veterinarian lecturing on this subject at Equitana, this means ulcers can start forming if the stomach is empty for as little as four hours. Slow-feeder hay-nets are a great way of slowing down hay consumption especially over-night.
Horses who are out at pasture 24/7 or otherwise housed with ad lib access to hay, are very unlikely to develop stomach ulcers. In fact a big part of the ‘cure’ for horses who have developed ulcers, apart from a short term course of medication, is 24/7 pasture turn-out or ad lib access to hay.
The clinical signs of ulcers include:
Loss of appetite / Going off their feed
Refusal to eat feed which contains salt – we all know what it feels like to rub salt into an open wound…………….
Unexplained weight loss
Stereotypies such as wind-sucking
Colic associated with feed time or exercise
Reflux - Accumulation of fluid in the gut
Less obvious signs for stomach ulcers include the following and you can see they could be confused with signs of being ‘Grass Affected’.
Twitching when touched – this is often one of the first signs the horse has mineral imbalances which are affecting nerve endings in the horse’s skin causing hyper-sensitivity. This can cause the horse to exhibit uncharacteristic behaviour such as aggression and/or nervousness
Girthiness, cold-backed, saddle-fitting issues, napping, ‘humping’ or bucking.
Poor performance in general
The only way to confirm the presence of stomach ulcers is to have your veterinarian scope the horse.
Ulcers can also form further down the intestinal tract in the small intestine, the caecum and the hind-gut. These are obviously harder to diagnose, samples of feces are tested for signs of blood.
Gastric Ulcers are most common in horses that perform athletic activities. 80-90% of race-horses have been found to suffer from ulcers and it is no wonder. Exercising on an empty stomach is a contributing factor. Apparently exercise not only increases gastric acid production and decreases blood flow to the gastrointestinal (GI) tract but also causes the acidic fluid in the stomach to splash around thereby subjecting the upper, more vulnerable portion of the stomach to damaging acidity.
When transporting horses for long distances it is wise to stop and unload them every couple of hours so they can have a graze or some hay. A few hours of transport has been known to induce stomach ulcers in previously healthy horses..
Prevention and Treatment
As always, prevention is preferable to treatment. Feed horses frequently or on a free-choice basis. Chewing generates saliva which is nature's best antacid.
Strong stomach acids are necessary not only for the breakdown of coarse fibrous material but also because absorption of calcium in particular and magnesium require an acidic environment. So treating horses for ulcers unnecessarily or for too long or feeding products which contain unprotected sodium bicarbonate can cause serious malabsorption. Horses should be treated for ulcers only when a diagnosis has been confirmed.
There are several approaches for the treatment of ulcers in horses:
1. Administer substances which NEUTRALISE the acid much like antacids in humans. However, for horses, the dose of antacids required to buffer the extremely low pH is very high and would need to be used several times a day to be effective.
2. administer substances which INHIBIT THE PRODUCTION of acid. Omeprazole for instance stops stomach acid secretion completely so you can see why you would not want to be using it except when necessary. There are other types of drugs which PARTIALLY block acid production.
3. Use of Mastic Gum which is effective but hard to get hold of.
Long term administration of some non-steroidal anti-inflammatory drugs (NSAIDs such as bute) can be detrimental to the stomach's protective mucus layer, making it more susceptible to ulcers. (Short term use does no harm and is preferable to the horse enduring unnecessary pain, especially when it comes to laminitis)
Obviously ANY treatment needs to be accompanied by appropriate lifestyle changes to prevent recurrences. Supplying plenty of forage will increase chewing time and saliva production which is the nature’s way of partially neutralising stomach acid.
Small-mesh hay-nets help the hay lasts longer – some horses need it to be double-bagged!