Biotin is a water-soluble B vitamin that has become one of the most widely supplemented nutrients in equine nutrition, primarily because of its well-documented role in improving hoof quality. The horse's hoof is made of keratin, a tough structural protein, and biotin is essential for the production of the intercellular cement that binds keratin fibers together into a strong, resilient hoof wall. Multiple controlled studies have demonstrated that biotin supplementation at therapeutic doses significantly improves hoof wall hardness, reduces cracking and crumbling, and accelerates the growth of healthy new horn — but it takes time. Because the hoof grows from the coronary band downward at roughly 6 to 10 millimeters per month, it can take 9 to 12 months of consistent supplementation before the full benefit is visible at the ground surface. Biotin also supports healthy skin, coat quality, and plays a role in fat and carbohydrate metabolism. Horses produce some biotin through hindgut bacterial fermentation, but this endogenous supply appears insufficient for horses with poor hoof quality, which is why supplementation at levels well above what hindgut bacteria provide has become standard practice for horses with chronic hoof problems.
A 500kg horse produces about 1 to 2 milligrams of biotin per day from hindgut bacteria — roughly the weight of a speck of dust. For horses with good hooves, this may be adequate. For horses with hoof problems, research supports supplementing 15 to 25 milligrams per day — about the weight of a small grain of rice. This therapeutic dose is well above what food alone can provide and requires a dedicated biotin supplement. Improvements take 9 to 12 months to grow out from the coronary band, so patience is essential.
0.0% of daily nutrient intake
Vitamin B7 (Biotin) makes up 0.0% of your horse's total daily nutritional requirements by weight. That's a tiny amount — but it matters.
Weak, crumbly, or cracking hooves, slow hoof growth, thin hoof walls that bruise easily, frequent lost shoes, dry or flaky skin, and a dull coat. True biotin deficiency is uncommon because hindgut bacteria produce some, but many horses appear to have sub-optimal levels for maximal hoof quality.
Biotin is water-soluble and excess is excreted in urine. No toxicity has been documented in horses even at high supplementation levels. It is one of the safest supplements available.
| Life Stage | Size | Min | Max | Unit | Notes |
|---|---|---|---|---|---|
| Adult | — | 1 | 3 | mg | Baseline from diet and hindgut synthesis. Horses with good hoof quality may not need supplementation beyond this. |
| Working / Active | — | 15 | 25 | mg | Therapeutic dose for horses with poor hoof quality. Research supports 15-25mg daily for 9-12 months to see full benefit in new hoof growth. |
Source: NRC 2007, general veterinary consensus
Biotin and zinc both play critical roles in hoof and skin health. Biotin provides the building blocks for keratin cross-linking, while zinc supports the enzymes involved in keratin production. Together they improve hoof wall strength and growth rate more effectively than either alone.
What this means: If supplementing biotin for hoof quality, also ensure zinc intake is adequate (400mg daily). Many hoof supplements combine both nutrients. Addressing zinc deficiency alone sometimes improves hoof quality enough to reduce or eliminate the need for high-dose biotin.
