The Use of a 10-Day Period for the Assay of Vitamin B by Rat Growth Technic

Abstract
A short period technic for vitamin B assays has been developed through a study of the factors producing variability in results. The amount of growth of the rat during 10 days was found to be a valid criterion of the quantity of vitamin B in the dose material if the following precautions had been observed. The quantity of vitamin B causing 1 gm. of gain, when the rate of gain has been limited to 1 to 2 gm. per day, is suggested as a unit since it is comparable to the minimum curative dose defined by Ammerman and Waterman.