Effect of pelleting on the vitamin K activity of various vitamin K3 preparations in chicks.

A study with chicks was conducted to compare the relative vitamin K3 stability of various menadione preparations in mash and pellets. The preparations assayed were menadione sodium bisulfite, menadione sodium bisulfite complex, menadione dimethylpyrimidinol bisulfite and Kastab (a physically stabilized preparation of menadione sodium bisulfite). Pelleting increased the stability of all preparations when measured by the partial thromboplastin assay. The general trend in stability obtained by both procedures was in decreasing order: Kastab, menadione dimethylpyrimidinol bisulfite, menadione bisulfite complex and menadione bisulfite. Stability, determined chemically in vitamin microelement premixes, gave similar results.