🌱 Vet Nutrition 2025: How Horses Digest Forage and Why It Matters 🐴🧬

Author: Dr Duncan Houston, BVSc

Unlike cows and other livestock, horses don’t have a rumen. Yet they’re still effective herbivores—thanks to their cecum, a fermentation vat located toward the end of their digestive tract. This unique design makes horses hindgut fermenters and explains why they need consistent, forage-based diets to thrive. In this 2025 vet guide, Dr Duncan Houston explains how horses digest forage and how to manage feeding in today’s confined environments. 🐎🌿

🔬 Horse vs. Cow: A Digestive Comparison

• 🐄 Cows (ruminants): Ferment food in a rumen at the beginning of the digestive tract
• 🐴 Horses (non-ruminants): Ferment food in the cecum near the end of the digestive tract

This means food in horses is partially digested before it reaches the cecum—so anything that bypasses the small intestine (like starches) may disrupt fermentation. 🧪

🌿 What the Cecum Does

The cecum houses microbes that ferment fiber from hay and grass, converting it into volatile fatty acids—your horse’s primary energy source from forage. 🔬

Functions of the Cecum:

• 🦠 Ferments cellulose and fiber
• 🔥 Produces energy as fatty acids
• 🧬 Synthesizes some vitamins and nutrients

Because it's located at the end of the digestive tract, the horse can't “chew its cud” like a cow to correct digestive issues—so prevention is key. ⚠️

⏱️ Why Feeding Frequency Matters

Horses evolved as continuous grazers, consuming small amounts of forage all day. But modern management often means two large meals per day in confinement. This mismatch leads to:

• ⚠️ Increased risk of colic and impaction
• 🔥 Acid buildup and gastric ulcers
• 🌀 Hindgut acidosis and founder (laminitis)

🛠️ Mimicking Natural Digestion in Modern Settings

1️⃣ Feed More Forage, Less Grain

• 🌾 Forage (hay or pasture) should make up at least 70–90% of the total diet
• 🚫 Limit grain to avoid undigested starch reaching the cecum

2️⃣ Offer Feed Frequently

• 🍽️ Small, frequent meals prevent gut stress
• 🧠 Consider slow feeders or hay nets

3️⃣ Maximize Turnout

• 🌳 Pasture access supports GI motility and mental health
• 📉 Reduced stall time = reduced colic risk

🧠 Dr Duncan Houston’s Tip

"Feeding your horse like a ruminant cow is a recipe for digestive trouble. Think like nature—constant, forage-first intake is the key to GI health." 🐴💬

⚠️ Common Issues from Forage Mismanagement

• 💥 Colic from impaction or fermentation disruption
• 🔥 Gastric ulcers from prolonged fasting
• 🧪 Hindgut acidosis from starch overload

📋 Final Thoughts: Feed with the Gut in Mind

Understanding how horses digest forage helps you design a feeding strategy that supports gut health, behavior, and performance. Stick to high-quality forage, feed frequently, and minimize concentrated grain feeds—and your horse’s digestive system will thank you. 🐎❤️

Need help with a forage-based feeding plan? Visit AskAVet.com or download the Ask A Vet app for expert guidance. 📱🌱