Influence of Raw and Whole Dried Liver on Food Consumption and Utilization. ∗

Abstract

In experiments described by Smith 1 it was shown that liver tissue extracted with alcohol until fat-free has a biological value inferior to that of whole liver, as shown by a subnormal growth rate. In the present experiments an attempt was made to gain information as to the manner in which whole liver exerts its favorable influence. A combination of the efficiency quotient method of Palmer and Kennedy 2 and the paired-feeding method used by Mitchell and Carman 3 was used. Male albino rats on a complete diet containing 20% extracted liver, 1 supplemented by 0.5 gm. of dried whole liver or 1.5 gm. of raw liver daily, and whose food intake was limited to that of control animals, grew at a faster rate and had lower efficiency quotients than did the controls. Animals receiving the supplements and having no restrictions in food intake consumed more food, but made greater gains and had somewhat lower efficiency quotients than those whose food intake was limited. When the diet was supplemented with an equivalent amount of alcohol-extracted liver (0.5 gm.), the animals with limited and with unrestricted food consumption made no greater, or but slightly greater, gains than did the control animals and also had similar efficiency quotients. In all, 8 experiments (24 animals) with the whole liver and 4 (12 animals) with the extracted-liver supplements were carried out. A typical experiment with each of the supplements is shown in Table I.

It appears, therefore, that the increased growth rate resulting from feeding whole liver is due to some influence other than an increased food consumption, and that the factor responsible for the growth-promoting effect is removed by alcohol.