Folate (vitamin B9) is essential for cell division and DNA synthesis, making it critically important during periods of rapid growth, tissue repair, and pregnancy. In your horse's body, folate works alongside vitamin B12 to produce healthy red blood cells and prevent megaloblastic anemia. For pregnant mares, adequate folate supports proper fetal neural development and placental growth. Fresh green pasture is the single best natural source of folate for horses — the name itself comes from the Latin word for leaf. Horses on hay-only diets receive less dietary folate, but hindgut bacteria produce significant amounts, which helps bridge the gap.
Your horse needs roughly 15 to 20 milligrams of folate per day — about the weight of a small pinch of baking soda. A 500kg horse on good-quality pasture or green hay with a healthy hindgut comfortably meets this requirement. Supplementation is generally unnecessary but may benefit pregnant mares or horses with compromised hindgut function from illness or prolonged antibiotic therapy.
0.0% of daily nutrient intake
Vitamin B9 (Folate) makes up 0.0% of your horse's total daily nutritional requirements by weight. That's a tiny amount — but it matters.
Folate deficiency is rare in horses with access to pasture or quality hay plus a healthy hindgut. Potential signs include anemia (pale gums, poor stamina, elevated heart rate at rest), poor coat quality, slow wound healing, and reduced fertility. Foals born to severely folate-deficient mares could theoretically show developmental issues, though this is extremely uncommon.
Excess folate is not a practical concern. It is water-soluble and rapidly excreted. No toxicity has been documented in horses from dietary or supplemental sources.
| Life Stage | Size | Min | Max | Unit | Notes |
|---|---|---|---|---|---|
| Adult | — | 15 | 20 | mg | For a 500kg horse. Fresh pasture is the best source. Hay-only diets rely more heavily on hindgut bacterial production. |
| Pregnant / Nursing | — | 20 | 30 | mg | Folate needs increase during pregnancy for fetal cell division and placental development. Ensure adequate green forage or consider supplementation. |
Source: NRC 2007
