Vet Strategies for Healthy Weight Loss in Horses 2025 🐴⚖️

By Dr Duncan Houston, BVSc

While much attention is given to underweight horses, obesity is a more common and growing problem in equine care. Overweight horses face increased risk for arthritis, poor performance, and dangerous metabolic diseases like laminitis and founder. In this 2025 veterinary guide, Dr Duncan Houston outlines effective, evidence-based methods to help your horse lose weight safely and stay sound for the long haul. 🐎📉

1. The Risks of Obesity in Horses ⚠️

Excess weight isn’t just an aesthetic issue—it’s a health threat. Overweight horses are more likely to suffer from:

• 🦴 Joint strain and arthritis
• 💥 Laminitis and founder
• 🐌 Reduced performance and stamina
• 🧬 Insulin resistance and Equine Metabolic Syndrome (EMS)
• 💊 Difficulty with medications or anesthesia

A landmark study in the UK found that horses gaining weight were more than twice as likely to develop laminitis as those maintaining or losing weight. This underscores the urgency of weight control—especially in sensitive breeds. 🧪

2. Know What’s “Too Much” – Body Condition Scoring 🧠

Weight tapes and visual cues alone aren’t always accurate. Instead, use the Body Condition Score (BCS) system, which evaluates fat deposits at key locations:

• 🐎 Neck crest
• 💪 Shoulder and withers
• 🧱 Ribs and backline
• 🍑 Tailhead area

Scores range from 1 (emaciated) to 9 (obese). Ideal is 4–6. A BCS of 7+ means it’s time to start a weight loss plan. ✅

3. How Horses Gain Weight ⚖️

Most horses gain weight from:

• 🍽️ Overfeeding calories (grain, hay, pasture)
• 🌾 Access to lush pasture high in sugar and starch
• 😴 Inactivity or stall confinement
• 🧬 Metabolic sensitivity (e.g., insulin resistance)

Even horses on what seems like a “normal” diet may gain weight if their activity is low or their feed is too energy-dense. Monitoring total calorie intake is key. 🧮

4. Feeding for Weight Loss: The 60% Rule 📉

To truly promote weight loss, Dr Duncan Houston recommends reducing total feed intake to 60% of maintenance requirements—not just "a little less." Here’s why:

• 🍽️ Feeding 80–90% may prevent further gain—but won’t shed pounds
• 🔻 60% provides a caloric deficit that triggers fat metabolism

Sample Calculation:

Maintenance for a 1,000 lb horse = ~15,000 kcal/day Weight loss target = ~9,000 kcal/day = Reduce hay or feed to reach 60% kcal, adjusting for nutrient density

5. Small Hay Nets = Big Results 🕸️

Using small-hole hay nets slows consumption, mimics natural grazing, and prevents boredom. A study from the University of Minnesota found:

• 🐴 Horses on the ground finished hay in half the time
• 🕸️ Horses using slow-feed nets consumed less while staying satisfied
• 🧠 This also reduced risk of ulcers and cribbing

Feed small meals frequently with hay nets to maintain digestive health while controlling intake. 🌾

6. Manage Pasture Access 🌿

Lush spring or irrigated pastures are packed with non-structural carbohydrates (NSC)—a major contributor to weight gain and laminitis. To limit risk:

• 🧢 Use grazing muzzles to reduce intake by ~80%
• ⏳ Restrict turnout time—early morning grazing is safer (lower NSC)
• 🚫 Avoid turnout during rapid grass growth or after frost

Future research is exploring exactly how long susceptible horses can graze safely with muzzles—so far, short, controlled windows are best. 🧬

7. Exercise Essentials: Move to Lose 🏃‍♀️

Exercise boosts calorie burn, improves insulin sensitivity, and supports muscle tone. Start with:

• 🚶 20–30 minutes of hand walking or lunging 5 days/week
• 🐎 Light riding or ground driving if cleared by a vet
• ⏳ Increase intensity and duration gradually

Even pasture turnout increases movement—but structured exercise is most effective. 🏇

8. Trim Regularly: Laminitis Prevention 🦶

The study found that horses trimmed or shod every 8+ weeks were slower to recover from foot soreness and more prone to laminitis. Stay ahead by:

• 📆 Scheduling trims every 6–8 weeks
• 👣 Monitoring hoof condition closely in overweight horses

Preventive care for the feet is essential during weight loss to avoid strain on laminitic tissues. 🦶🔥

9. Common Mistakes to Avoid ❌

• ⚠️ Cutting calories too quickly—can cause behavior issues or ulcers
• ❌ Removing all forage—leads to digestive upset
• 📏 Guessing weight—use a scale or regular weight tape checks
• 🧂 Over-supplementing—excess minerals can worsen fat retention

10. Tools for Tracking Progress 📈

• 📏 Weight tape weekly
• 📸 Side-view photos every 2 weeks
• 🧠 Record BCS regularly
• 📱 Use apps or spreadsheets to log feed and changes

Set realistic goals: 1–2% body weight loss per month is safe and sustainable. 🗓️

11. Breeds at Higher Risk for Weight Issues 🧬

• 🟫 British native ponies
• 🦄 Miniatures and easy keepers
• 🐴 Horses with prior laminitis episodes
• ⚠️ Insulin-resistant or Cushing’s (PPID) horses

These horses often need stricter calorie control and regular monitoring—even when they appear healthy. 🔍

12. Summary Table: Weight Loss Plan for Horses 📋

13. Final Thoughts from Dr Duncan Houston 💬

Weight loss in horses is a challenge—but a worthy one. Done correctly, it reduces the risk of life-threatening laminitis, improves joint function, and boosts your horse’s comfort and performance. 🐴

If you need help building a weight loss plan tailored to your horse’s breed, lifestyle, or health conditions, visit AskAVet.com or download the Ask A Vet app 📲 for trusted, 24/7 support from equine veterinarians.

— Dr Duncan Houston, BVSc