Too little Vitamin E
Vitamin E acts as an antioxidant for lipids in cell membranes. Vitamin E has a samilar functions as selenium. Deficiency leads to muscle dystrophy (white muscle disease) and to uncoordinated movements and lameness.
Solutions: Concentrates and most vitamin/mineral mixtures for horses contain vitamin E. Special vitamin/mineral mixtures for vitamin E and selenium are marketed in most countries.
Too much Vitamin E
Moderate over feeding of vitamin E has no proven detrimental effect, in fact recommendations for vitamin E intake have increased over the last two decades.
Too much may however affect the utilization of other lipid soluble vitamins (A, D and K).
Solutions: Consider reducing use of high vitamin E feeds and supplements.