Horse gastric ulcers: a feeding rhythm that protects the stomach

Quick answer

Equine gastric ulcer syndrome is not one disease. It is two, in two different parts of the same stomach, with different causes and different treatments, and the feeding routine that helps one does not automatically help the other.

What both share is that the horse's stomach secretes acid continuously, whether or not there is anything in it. A horse was built to eat for most of the day. A stabled horse fed two or three meals is empty and acidic for long stretches, and the routine that protects it is the one that keeps forage moving through the gut and keeps starch meals small.

The hard feed is the part everyone measures. The forage between the hard feeds is the part that actually protects the stomach.

• Acid is produced constantly. Only chewing forage produces the saliva that buffers it.
• Long gaps with no forage are the single most modifiable risk factor for squamous ulceration.
• Large starch meals ferment in the stomach and damage the upper stomach lining. Split them and keep them small.
• Never exercise a horse on a completely empty stomach.
• Gastric ulcers can only be confirmed by gastroscopy. No supplement, blood test or response to feeding proves or excludes them.

Decide in 60 seconds

Why the horse's stomach works this way

A grazing horse spends the majority of its day with its head down, taking small mouthfuls and chewing constantly. Chewing is what triggers saliva, and equine saliva is rich in bicarbonate. That constant trickle of buffer, arriving with a constant trickle of fibre, is the system the stomach evolved around.

Acid production does not pause between meals. In a stabled horse fed at set times, the stomach spends hours acidic and empty, and the acid pools and splashes.

The upper stomach is where that matters most. It is lined with squamous tissue that is essentially the same kind of surface as the oesophagus, and it has none of the mucus and bicarbonate defences that the lower glandular stomach has. It was never intended to be in contact with acid at all. When the stomach is empty and the horse moves, acid washes upward onto it.

The lower, glandular stomach is different. It is built to sit in acid and defends itself actively. When glandular disease occurs, it is generally a breakdown of those defences rather than simple acid exposure, and the risk factors that show up most consistently are workload, stress, frequent changes of handler or routine, and lack of rest days. Feeding management alone often does not resolve it.

Starch adds a second mechanism. Cereal starch that is not fully digested in the small intestine ferments and produces volatile fatty acids. In an acid environment those acids cross into the squamous cells and damage them. This is why one large scoop is worse than the same amount split across two feeds, and why high starch feeds carry more risk than fibre and oil based ones.

Water matters more than it seems. Reduced water intake is associated with increased ulcer risk, and a horse whose automatic drinker is faulty or whose winter water is uncomfortably cold drinks less without anyone noticing.

What a protective feeding rhythm looks like

Forage available for as much of the day as possible.

The aim is not a set number of feeds per day. It is the absence of long empty gaps. Gaps of more than about six hours without forage are widely regarded as a meaningful risk factor, and overnight is where most yards create them accidentally.

Slow the forage down rather than adding more of it.

For a good doer that cannot have unlimited hay, small-holed nets, double netting, and several small piles spread around the box or field stretch the same weight of forage across far more hours. This is the practical answer to the conflict between ulcer prevention and weight control.

A small-holed net turns the same weight of hay into many more hours of chewing, which is the part that produces buffering saliva.

Keep hard feed meals small and frequent rather than large and few.

Splitting the daily concentrate into more, smaller meals reduces the starch load reaching the stomach at any one moment. Your vet or an equine nutritionist can set the ceiling per meal for your horse's bodyweight and workload.

Weigh the hard feed.

A scoop is not a unit. The same scoop holds very different weights of different feeds, and yards routinely feed twice what they think they do. Weigh it once, mark the level on the scoop, and everyone on the yard feeds the same amount.

Weigh the concentrate once and mark the scoop. Meal size is the part of ulcer management most often estimated and most often wrong.

Feed forage before exercise.

A small amount of forage shortly before work puts a fibre mat in the stomach and reduces the acid splashing that exercise causes. This is one of the most consistently recommended and least followed pieces of ulcer management.

Ask your vet about forage type, including alfalfa.

Alfalfa is high in calcium and protein and has a buffering effect, and it is commonly recommended as part of squamous ulcer management. It is not universally appropriate, and there is evidence it may not suit every horse with glandular disease. This is a decision to make with the vet who scoped your horse, not from a general rule.

Turnout, company and routine.

Horses at grass with company are exposed to fewer of the risk factors that drive glandular disease. Where full turnout is impossible, consistency of handler and routine, rest days in the work programme, and visual and social contact with other horses all pull in the same direction.

Water, always, and check it.

Constant access to clean water at a temperature the horse will actually drink. Check automatic drinkers physically rather than assuming they work.

Signs that mean act today

Complete loss of appetite in a horse that normally eats.

A horse that walks away from feed has something significant going on. This is a same-day veterinary call.

Rolling, pawing, repeatedly getting up and down, looking at the flank.

Colic. Ring the vet, take food away, keep the horse safe and observed. Do not administer painkillers unless your vet has told you to, because masking pain makes the assessment harder.

Sudden reluctance to be girthed, or a marked change in behaviour under saddle.

Pain of some kind. It may be gastric, musculoskeletal, dental or tack related, and all of those need investigating rather than training through.

Weight loss, dull coat, poor performance developing over weeks.

Chronic and easy to normalise. Bring it up with the vet even when nothing seems acute.

Abnormal mucous membranes.

Assessing gum colour and capillary refill is a genuine equine skill and it is part of every colic assessment, but it is a check on the circulation, not on the stomach. Pale, brick red, purple or blue membranes with a slow refill mean the horse is compromised and needs a vet immediately. Normal membranes do not rule out ulcers.

No droppings, or a horse that has stopped passing manure.

Call the vet. Gut motility has stopped and that is an emergency regardless of the cause.

The routine that catches problems early

Watch the horse eat, at least once a day, and know how long it normally takes to finish a feed. A horse that starts eating more slowly is telling you something before it loses any weight.

Check the net or the pile at the times when gaps happen. Late night and early morning are when the empty stretch usually hides.

Weigh or tape the horse regularly and write the numbers down, so a slow decline becomes visible.

Note the manure. Count of piles, consistency, and whether there is undigested fibre in it.

Have teeth checked on schedule by an equine dental technician or vet. Dental pain and gastric pain produce a similar picture, and one is far easier to find.

What never to do

Do not leave a horse with no forage overnight because it "has plenty during the day".

Do not exercise a horse straight from an empty stable with an empty stomach.

Do not feed a large cereal meal to make up for a missed one. Two small feeds are safer than one double.

Do not diagnose ulcers from a supplement label or from a horse seeming better on a feed change. Gastroscopy is the only way to know which form of disease is present and whether it has healed.

Do not stop a prescribed course of treatment early because the horse looks better. Healing and looking well are not the same point in time, and your vet may want to rescope.

Do not put an ulcer supplement alongside prescribed medication without asking, because some products alter how the medication is absorbed.

Do not change several things at once. If you alter forage, hard feed, turnout and workload in the same week, you will not know what helped.

Do not treat sudden severe abdominal pain as an ulcer flare and wait. Colic is a different emergency and it does not wait.

When to get help

Call an equine veterinarian immediately for signs of colic, complete loss of appetite, absent droppings, sweating, a horse that is dull and unresponsive, or abnormal mucous membranes with slow capillary refill.

Book a routine appointment for gradual weight loss, poor coat, slow eating, girthiness, a drop in performance, or behaviour changes under saddle, and ask specifically about gastroscopy.

A horse in good condition, eating steadily, with forage still in front of it. Continuity is the whole point.

Bring the full daily routine in writing: forage type and weight, hard feed type and weight per meal, feed and forage times including overnight, turnout hours, work programme, travel frequency, and any recent changes of yard, field group or handler. Gastric disease is managed on that information as much as on the scope findings.