Vitamin K deficiency occurred in two to 4 weeks in chickens on a simplified corn-soy ration, or on the modified vitamin K-low Animal Nutrition Research Council reference broiler ration. A water-soluble menadione sodium bisulfite complex containing 63% of menadione sodium bisulfite, U.S.P., proved three times as effective as menadione as a sole source of vitamin K in the modified A.N.R.C....