Rumen Synthesis of the Vitamin B Complex on Natural Rations. ∗ †

Abstract

Summary

Six members of the vitamin B complex in the rumen ingesta of a heifer fed a ration composed of natural feeds were determined. In most cases higher values were found in the rumen ingesta than in the ration fed. With the exception of flavin, variation of the amount of urea or protein in the grain mixture of the ration had little if any effect on the vitamin content of the ingesta.