When you think about the most interesting part of a horse, you might think of their lithe, agile body or their deadly hooves. Yet, the most unique part of the horse is their digestion. It’s not like the human digestive system with a simple stomach, but it’s also not the complex stomach of similar grass eating animals. In fact, the horse’s digestive system combines features of the simple and complex stomach to efficiently process fibrous plant material as well as meeting their high-energy needs.

Table of Contents

• Why a Horse’s Digestive System Matters
• Simple vs. Complex Stomach: What’s the Difference?
• Common Digestive Issues in Horses
• Understanding Equine Digestion for Better Care

Why a Horse’s Digestive System Matters

         Horses evolved to be efficient hind gut fermenters as they normally forage for 18 hours per day and intake a small amount of diverse food each time they eat. This means they don’t need the multiple chamber stomach that cows and sheep have to thoroughly digest plants.

Their process “maximizes sparse amounts of protein in their forage, conserve urea, avoid amino acid deficiency and work symbiotically with bacteria for essential nutrient synthesis” (https://theanimalsynergist.com/equine-nutrition-the-evolutionary-origin-hind-gut-fermentation/). The horse’s digestive system may be efficient in this sense, but it is easily disturbed by changes in their diet.

Simple vs. Complex Stomach: What’s the Difference?

         Typically animals that have a single stomach chamber, otherwise known as a simple stomach, are carnivores. This is because meat is easily digested compared to most plants.

On the other hand, animals that have multiple stomach chambers and a longer digestive tract have a complex stomach. They are usually herbivores who need fermentation for the proper digestion of cellulose found in plants.

Common Digestion Issues in Horses

         As mentioned above, their efficient yet fragile digestive system evolved to digest a variety of forage for an extended amount of time. Yet, with the domestication of horses, humans have changed their diet in a way that is unsuitable for their digestive system. This causes a variety of issues including:

• Colic (Severe Abdominal Pain):
  • Causes: Gas buildup, impaction, twisted intestines, sudden diet changes, dehydration.
  • Symptoms: Pawing, rolling, sweating, loss of appetite, restlessness.
• Gastric Ulcers (Stomach Lining Erosion)
  • Causes: High-grain/low-forage diet, stress, long periods without eating.
  • Symptoms: Weight loss, poor appetite, behavioral changes, teeth grinding, girth sensitivity.
• Diarrhea (Loose or Watery Stool)
  • Causes: Sudden diet changes, infections, parasites, stress, sand ingestion.
  • Symptoms: Loose stool, dehydration, lethargy, loss of appetite.

Understanding Equine Digestion for Better Care

         So, by understanding the delicacy of the horse’s digestive system, we ought to strive for more suitable strategies to maintain their health and wellbeing. Some methods include providing small, frequent meals to maintain digestive balance, avoiding extended periods without food, and restricting grain intake to minimize the risk of hindgut imbalances and digestive issues. Instead of feeding them what’s most convenient for us, it’s time we think about what’s most appropriate for them.