A horse’s gut runs 24/7, breaking down feed, absorbing nutrients, and fuelling everything from muscle power to mental focus. But it’s also a delicate system that can get off track quickly if diet, workload, or management changes.
With the right approach, you can help your horse get the most from every mouthful while reducing the risk of colic, ulcers, and other gut problems.
How to spot early gut health issues
Experienced owners recognise the obvious signs, but gut issues often begin with subtle changes.
Visible changes:
• Manure that’s consistently looser, drier, or less frequent than normal
• Leaving feed unfinished, eating slower, or suddenly refusing certain feeds
• Weight loss despite eating well
Under saddle:
• Reduced stamina or quicker muscle fatigue
• Reluctance to go forward, hollowing, or refusing specific movements
• Mood changes such as girthiness, irritability, or a “shut down” attitude
Measurable indicators:
• Body condition score dropping despite regular rations
• Poor topline despite adequate protein
• Recurring mild colic or diarrhoea
Did you know? A horse’s stomach is small (roughly the size of a rugby ball) and can empty in less than an hour, which is why long gaps between feeds can cause problems.
Main digestive conditions – and why prevention matters
Gastric ulcers
Gastric ulcers are more common in performance horses, especially those on high-grain diets or travelling often. Their reduced grazing means more stomach acid and less saliva to buffer it. Sometimes you’ll see clear signs, like girthiness or loss of appetite, but often it’s just a horse going “off the boil.” A diagnosis requires a gastroscopy. Treatment will usually pair medication with increased forage access and strategic feeding before work. A practical tip for you? Aim for forage with NSC below 12% for ulcer-prone horses.
Hindgut acidosis
Hindgut acidosis happens when excess starch bypasses the small intestine and ferments in the hindgut, dropping pH and disrupting fibre digestion. You might notice weight loss, loose manure, or subtle performance dips. Prevention is about keeping starch under 1 g/kg bodyweight per meal, boosting forage, and using hindgut buffers or targeted probiotics. Faecal pH testing is a valuable monitoring tool for this condition.
Colic
Colic broadly covers everything from mild gas build-up to serious impactions. The risks of colic include sudden feed changes, dehydration, sandy paddocks, and extreme weather shifts. In sandy regions, especially, monthly psyllium “sand clear” cycles are worth discussing with your vet. Any sign of colic, no matter how mild, is a sign to call your vet.
Stress vs digestion issues: How to tell the difference
Stress and gut problems share many signs, which can make diagnosis tricky. The key is to look for patterns, such as when they occur, what triggers them, and whether they persist once the trigger is removed.
| Possible stress signs | Possible digestion signs |
|---|---|
| Appears mostly in new environments or during travel | Consistent at home and away |
| Linked to loud noises, new horses, or competition atmosphere | Linked to feed changes or meal timing |
| Heart rate spikes during trigger, then settles | Manure changes, bloating, or recurring girthiness |
| Appetite returns once your horse is calm | Appetite fluctuates regardless of stress level |
| Behaviour improves with groundwork, turnout, or calmers | Behaviour improves with dietary adjustments or gut supplements |
Sometimes stress triggers gut issues, especially in ulcer-prone horses. If you’re unsure, track symptoms alongside workload, feeding, and environment for 2–3 weeks, then review with your vet or nutritionist.
Feeding and management to protect gut health
Think of these as your non-negotiables – the foundation to get right before you think about adding supplements or fine-tuning the diet. Even the best gut health product won’t fix problems caused by inconsistent feeding, poor forage access, or sudden changes.
Core practices for a healthy gut:
• Feed forage first – 1.5–2% of bodyweight daily in hay or pasture, spread across the day.
• Always feed forage before grain/concentrates to buffer stomach acid.
• Transition feed over 7–10 days to protect hindgut microbes.
• Giving multiple small meals will help reduce starch overload in the hindgut.
• Make sure to provide fresh, clean water available at all times. Add electrolytes in hot weather or after heavy sweat loss.
• Regular low-impact exercise and movement support gut motility and circulation.
Best practice tips
These are practices you might already be doing, but when applied strategically, they make a measurable difference. The last column highlights when they’re most relevant, and when to adjust or avoid.
| Best practice tip | Why it works | When to use / cautions |
|---|---|---|
| Lucerne hay before work | Buffers stomach acid for ulcer-prone horses | Best for horses in moderate–heavy work or prone to gastric ulcers. Avoid excess in easy keepers or laminitis-prone horses due to higher calorie and calcium content. |
| Psyllium husk monthly (in sandy areas) | Reduces sand colic risk | Use for horses in sandy soil regions or in drought-affected paddocks. Overuse may reduce absorption of other nutrients so always follow label guidelines. |
| Faecal pH/manure scoring every 3–6 months | Acts as an early warning for hindgut imbalance | Most useful for performance horses, those with digestive history, or after feed changes. Abnormal results should be interpreted with a vet or nutritionist before making drastic changes. |
Choosing digestion supplements
Supplements are the icing, not the cake – but in the right situations, they can take a horse from “managing” to “thriving”. Here are a few popular picks:
Poseidon Digestive EQ: This supplement combines marine-sourced calcium for acid buffering, lucerne leaf for fibre, mycotoxin binder, prebiotics, glutamine, and digestive enzymes. It’s great for ulcer-prone horses or those with loose manure after feed changes.
High Horse Gut Health Supplement: This supplement uses fermentable fibre for a natural prebiotic effect, buffers both foregut and hindgut, and is low in sugars/starch. It helps with scouring, sand colic risk, or poor nutrient absorption.
Kohnke’s Mag E: This supplement is primarily organic magnesium with Vitamin E and B1 for nerve and muscle support. Calmer horses often digest better, so it’s ideal for travellers or competition horses prone to stress-related gut upset.
Want more help?
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