Abstract
Increasing the concentrations of thiamine, riboflavin, pyridoxine, niacin, pantothenic acid, choline, p-aminobenzoic acid, and inositol used in synthetic mixtures as sources of the vitamin B complex resulted in marked increases in growth and pronounced increases in food utilization. However, increases in nitrogen retention and protein synthesis occurred only within a narrow range of the low concentration of the vitamin B complex. The marked increases in growth are due largely to fat synthesis from the carbohydrate (cerelose) in the rations. On a low 7.1% protein level some growth was possible, but only when the various components of the vitamin B complex were raised to high concentrations. On the same low protein intake and on a low concentration of the B vitamins, only maintenance was obtained. These observations were made during a one-week experimental period. The results of feeding aqueous butyl alcohol extracts of 1:20 Wilson's concentrate powder as a source of unknown components of the vitamin B complex were negative as far as utilization of casein for growth is concerned.