Amino Acid Requirements of the Chick

NUMEROUS reports have appeared which indicate that arginine is essential in the diet of the chick. Almquist (1947) estimated the chick's arginine requirement to be 1.2% in a 20% protein diet. A later report by Almquist and Merritt (1950) indicated the requirement to be 6% of the dietary protein in diets with from 15 to 30% protein. Several investigators (Young et al., 1953; Wietlake et al., 1954; Griminger et al., 1955; Snyder et al., 1956; Fisher et al., 1956; Krautmann et al., 1957; and Hogan et al., 1957) have reported that the chick's requirement for arginine is higher than this when fed a diet in which casein provides most of the protein. Snyder et al. (1956) and Krautmann et al. (1957) obtained no growth response by the addition of arginine to practical type corn-soybean diets although they calculated the arginine level of these diets to be below 1.2%. They suggest …