Riboflavin supports cellular energy production, healthy skin, eye function, and red blood cell formation. Horses receive riboflavin from forage, grains, and hindgut bacterial synthesis. Good-quality green hay and fresh pasture are reliable sources. Riboflavin is water-soluble and any excess is excreted efficiently.
A 500kg horse needs about 20 milligrams of riboflavin per day — roughly the weight of a few grains of sugar. This is comfortably met by a standard hay ration and hindgut bacterial production. Most commercial feeds also include supplemental riboflavin.
0.0% of daily nutrient intake
Vitamin B2 (Riboflavin) makes up 0.0% of your horse's total daily nutritional requirements by weight. That's a tiny amount — but it matters.
Lacrimation (excessive tearing), skin lesions, poor coat condition, and reduced growth. True riboflavin deficiency is very rare in horses eating a normal forage-based diet.
Riboflavin is water-soluble and excess is excreted readily. Toxicity from dietary sources is not a concern.
| Life Stage | Size | Min | Max | Unit | Notes |
|---|---|---|---|---|---|
| Adult | — | 20 | 40 | mg | For a 500kg horse. Provided by forage and hindgut bacteria. Green hay and alfalfa are reliable dietary sources. |
Source: NRC 2007
