Amino Acid Requirements of the Chick: 2. Effect of Total Essential Amino Acid Level in the Diet on the Arginine and Lysine Requirements

Abstract

THE chick's arginine requirement is higher when a purified type ration containing casein as the main source of protein is fed, than it is when a practical type corn-soybean oil meal ration is fed. It has been proposed that the practical type diet contains substance(s) which spare arginine. Several substances are known which will increase the growth rate of chicks fed arginine-deficient rations, but no one has claimed that these substances account for the difference in arginine requirement noted on the two types of rations mentioned. Reports supporting these statements have been reviewed in a previous paper on the effect of thyroxine on the chick's requirements for three amino acids (Fluckiger and Anderson, 1959). In the experiments on arginine requirement reported in the previous paper, three different purified type rations were fed. The three rations contained about the same percent protein, but differed in the kind of proteins included. The …