Menadione Nicotinamide Bisulfite (Source of Vitamin K) - Feed Ingredient

Menadione Nicotinamide Bisulfite (MNB) is a synthetic, water-soluble compound used as a source of Vitamin K activity in animal nutrition. It is a bisulfite derivative of menadione (Vitamin K₃) complexed with nicotinamide (Vitamin B₃). This formulation improves the stability and handling of menadione, which in its pure form is relatively unstable and sensitive to oxidation.

In equine feed formulations, MNB serves as a supplemental source of Vitamin K, a fat-soluble vitamin involved in blood clotting and bone metabolism. Horses can synthesize Vitamin K in the hindgut through microbial fermentation, but supplemental is not essential.

Due to its synthetic origin, Menadione Nicotinamide Bisulfite is not bioidentical to phylloquinone (Vitamin K₁) or menaquinones (Vitamin K₂), the natural forms of the vitamin. Nonetheless, it is widely used in feed manufacturing because of its cost-effectiveness, shelf stability, and ease of inclusion in premixes and pelleted feeds.