Grain-Free and Thriving: Why a Grain-Free Diet Can Benefit Your OTTB

Off-Track Thoroughbreds (OTTBs) are beautiful, athletic, and often incredibly sensitive horses. At Fiordland Equestrian Thoroughbred Rehabilitation Program (FETRP), our mission is not only to retrain and rehome these horses but also to restore their physical and mental well-being. One of the most powerful tools we’ve found in this process? Nutrition—specifically, grain-free feeding.

Grains like corn, oats, and barley are a staple in most traditional racehorse diets. They’re high in calories, fast-burning, and perfect for fueling short bursts of intense energy. But once an OTTB leaves the track, their energy needs shift dramatically. Many struggle with digestive problems, metabolic stress, or behavioral issues that are exacerbated by grain-based diets.

We’ve transitioned all of our Thoroughbreds to grain-free diets—and the results speak volumes.

Benefits of a Grain-Free Diet for OTTB's

1. Mental Clarity & Emotional Stability

One of the first things many owners report after removing grain from their OTTB’s diet is a noticeable change in behavior.

Grains are rich in non-structural carbohydrates (NSCs), which quickly break down into sugars and can cause blood sugar spikes. For horses with sensitive systems—like most OTTBs—this can result in sudden bursts of nervous energy, over-reactivity, and even anxiety.

At FETRP, we’ve seen previously anxious horses become calm and manageable within weeks of switching to grain-free feed. A more balanced diet helps keep their minds level, which is critical during the retraining phase when they’re learning how to become riding partners instead of race machines.

2. Digestive Health: Healing from the Inside Out

OTTBs often come off the track with compromised digestive health. The demands of racing—along with stall confinement, stress, and a diet heavy in starch and low in fiber—create a perfect storm for gastrointestinal issues like ulcers, colic, and hindgut acidosis.

Grains ferment rapidly in the hindgut, creating an acidic environment that kills off good bacteria and sets the stage for digestive problems.

Switching to a forage-based, grain-free diet gives the gut a chance to heal. We prioritize:

• Free-choice hay or slow-feeder access to keep the digestive system moving.

• Beet pulp or hay pellets as a soft, fermentable fiber source.

• Alfalfa for its natural calcium content, which can help buffer stomach acid.

• Probiotics and digestive supplements to restore microbial balance.

The difference in manure quality, appetite, body condition, and overall comfort is usually evident in just a few weeks.

3. Stronger Hooves, Shinier Coats

Grain-free diets aren’t just about calming behavior or improving digestion—they also promote radiant health from the outside in.

High-starch diets have been linked to systemic inflammation, which can manifest in poor hoof growth, thin soles, dull coats, and chronic skin conditions. On the other hand, a forage-rich, grain-free diet that includes omega-3 fatty acids (from flaxseed or chia), balanced minerals (especially zinc and copper), and amino acids supports strong, healthy hoof horn and gleaming coats.

At our facility, we’ve seen barefoot OTTBs go from shelly, cracked hooves to sturdy feet capable of handling turnout and trail work within a season on a grain-free plan.

4. Energy—But the Right Kind

A common myth is that grain-free means low energy—but this couldn’t be further from the truth.

Instead of quick-burning starches, grain-free diets rely on slow-release energy sources like fiber and fat. These provide the sustained energy that OTTBs need for consistent, moderate work. The result? A horse that feels fueled and forward, but not frantic or fizzy.

We often use combinations like:

• Beet pulp or hay pellets for digestible fiber-based calories.

• Flaxseed or stabilized rice bran for fat-based energy.

• Alfalfa cubes or chopped forage for variety and additional protein.

Horses maintain body weight beautifully and have steady stamina without the dramatic highs and lows that come with traditional grain.

5. Metabolic Protection for the Long Haul

As OTTBs transition into their new lives—whether that’s trail riding, low-level eventing, dressage, or just being a companion—they no longer require the high-calorie, high-carb diets of their racing days. In fact, continuing to feed grains can increase the risk of metabolic disorders over time, including insulin resistance, Cushing’s, or laminitis.

Grain-free diets naturally support metabolic health. By limiting sugar and starch, you’re keeping insulin levels in check, reducing systemic inflammation, and supporting longevity.

Even for easy keepers or retired Thoroughbreds, a well-formulated grain-free plan can provide the nutrition they need without the risks.

Making the Transition: What It Looks Like

Switching to a grain-free diet doesn’t mean your horse goes without proper nutrition. It just means feeding smarter.

Here’s a basic example of a typical FETRP grain-free feeding plan:

Base:

• Free-choice grass hay (tested for nutritional value)

• Alfalfa cubes or pellets (1–2 lbs per feeding)

• Beet pulp (rinsed and soaked)

Add-ons:

• Flaxseed (½ to 1 cup daily)

• Comprehensive vitamin/mineral balancer (specifically formulated for forage-based diets)

• Electrolytes or salt block

Optional supplements:

• Gut support (yeast, pre/probiotics, or herbal blends)

• Joint or hoof support (biotin, MSM, collagen)

Always make changes gradually over 7–14 days and consult your vet or equine nutritionist to ensure your OTTB’s individual needs are met.

Real Results, Real Stories

We’ve had OTTBs come in with varying body scores, riddled with ulcers, ribby, shaggy and dull-coated, and some too reactive to safely handle. Within three months of a grain-free diet and a thoughtful rehab program, they become strong, shiny, and mentally present.

The glow-up is real.

Final Thoughts: A Better Way Forward

Feeding an OTTB is about giving them the right foundation to succeed. While grain-based diets are traditional, they’re often more about convenience than what’s truly best for the horse—especially a horse recovering from the demands of racing.

By going grain-free, you’re honoring your horse’s natural physiology, promoting long-term health, and supporting a smoother transition to their new life.

Whether you’re retraining your OTTB for competition or just looking for a healthy, happy pasture partner, consider this: sometimes, less really is more.

Want to learn more?

Follow along for more nutrition tips, OTTB care guides, and behind-the-scenes stories from the barn. And if you’ve had success with a grain-free diet, we’d love to hear your story in the comments!