Introduction 🐎

Feeding a horse may seem straightforward, but proper equine nutrition is complex and critical. From preventing ulcers to balancing forage and concentrates, every element of your horse’s diet should be tailored to their physiological needs, lifestyle, and work level. Dr Duncan Houston breaks down modern, evidence-based strategies to help your horse thrive in 2025 and beyond.

1. Gastric Ulcers and Feeding Frequency 🧪

Gastric ulcers affect up to 90% of racehorses, and feeding frequency is a major contributor. Horses produce stomach acid around the clock, but only produce saliva—acid’s natural buffer—when they chew:

• ⏰ Continuous acid production: Stomach acid flows 24/7.
• 🍽️ Saliva only during chewing: Buffering occurs with forage intake.
• 📉 Large, infrequent meals: Increase ulcer risk due to prolonged acid contact.

Grazing throughout the day allows natural buffering. Stalled horses fed twice daily are at the highest risk.

2. How the Horse’s Digestive System Works 🌿

Dr Duncan Houston explains that while horses are large animals, their stomachs are surprisingly small:

• 🧪 Stomach volume: Only 2–4 gallons in a 1,100 lb horse.
• 🕒 Retention time: Food remains for 1–5 hours depending on texture and moisture.
• 💩 No gallbladder: Bile flows continuously into the small intestine.
• 🧫 Fermentation in the hindgut: Microbial digestion happens after the small intestine.

3. Ulcer Treatment Cautions ⚠️

While omeprazole is the leading treatment for gastric ulcers, it’s not without side effects:

• 🧫 Alters stomach pH: May encourage bacterial overgrowth.
• 🦴 Impacts calcium balance: Raises fracture risk with long-term use.
• 📉 Limited duration studies: One study showed no calcium effects after 60 days—but long-term impacts remain uncertain.

4. The Role of Forage in Horse Nutrition 🍀

The foundation of every horse diet should be high-quality forage. According to Waltham Equine Centre:

• 🌱 Pasture or hay: Provides essential fiber, energy, and chewing time.
• 📉 Many horses don’t need grain: Forage plus vitamins/minerals is often sufficient.

Most horses consume 1.5% of their body weight in dry forage per day. For a 1,000 lb horse, that’s ~15 pounds total. Ponies may consume 3–5% of their weight!

5. Pasture vs. Hay Intake Calculations 🌾

Dr Duncan Houston offers a pasture-based hay calculation guide:

• 🌅 24-hour turnout: Feed <25% of hay ration (if pasture quality is good).
• 🌞 8–12 hours pasture: Feed 25–50% of hay ration.
• ⏳ 4–8 hours pasture: Feed 50–75% of hay ration.
• 🚫 No turnout: Feed 100% of hay ration.

6. Complementary Feeds: What’s Changed 🔄

Modern complementary feeds aren’t just high-starch anymore. Today’s options include:

• 🍠 Beet pulp: Highly digestible fiber.
• 🌻 Vegetable oil: Clean energy from fats.
• 🧪 Vitamin/mineral fortification: Ensures balanced micronutrient intake.

These feeds should be given in full recommended amounts—usually 2 lbs per 1,000 lbs horse—to meet vitamin and mineral needs. Feeding less? You’ll need to supplement.

7. Ration Balancers: The Smart Middle Ground ⚖️

Ration balancers provide:

• 💪 Protein
• 💊 Vitamins & minerals
• 🚫 No extra energy

They’re ideal for horses in light work who don’t need extra calories. Add to forage to complete the diet.

8. Feed Ingredient Balance: Calcium vs. Phosphorus ⚗️

Feeding single grains like corn is risky. Here's why:

• 🌽 Corn: High phosphorus, low calcium.
• 🍬 Beet pulp/alfalfa: High calcium, low phosphorus.

An imbalance can cause developmental orthopedic disease in foals or bone weakness in adults. Stick with commercial feeds unless you’re formulating under vet guidance.

9. Water: The Overlooked Nutrient 💧

Water is the most important and often overlooked part of the diet. Horses need:

• 🚰 5–10 gallons per day, more in hot weather or with exercise.
• ❄️ Warm water in winter to prevent colic.
• 🧽 Clean, regularly checked sources—dirty buckets reduce intake.

10. Summary: Dr Duncan Houston’s Nutrition Formula 📘

• 🍃 Forage first: Meet at least 1.5% of body weight daily.
• ⚖️ Balance with vitamins/minerals: Use ration balancers or full complement feeds.
• 🍽️ Small, frequent meals: Prevent ulcers and aid digestion.
• 🚫 Don’t overfeed grain: Especially for easy keepers.
• 💧 Hydrate! Water drives every metabolic process.

Need Help Building a Nutrition Plan? Ask A Vet! 📲

Confused about feeding amounts, supplements, or hay quality? Connect with Dr Duncan Houston through the Ask A Vet app. Get personalized nutrition support, forage analysis, and supplement advice—right from your phone! 🐴📈