Studies on the Sulfur Amino Acid Requirement of the Chick

IN A REVIEW of the amino acid requirements of the chicken, Almquist (1952) reported that the sulfur amino acid requirement appeared to be 0.8% of a diet containing 20% protein. This is the present requirement of the National Research Council (1954). Almquist also stated that the requirement for methionine and other essential amino acids increased as the protein content of the diet increased, but not to the same extent. He further noted that approximately 0.1% more methionine is required in the diet for maximum efficiency of feed utilization than is required for maximum growth. Hill (1953) reviewed the methionine and cystine requirements of the chick and concluded in agreement with Almquist (1952) that the total requirement for sulfur amino acids did not exceed 0.8% of a diet containing 20% protein. The results of three preliminary experiments reported in part by Hill (1953) showed that methionine added to practical broiler diets …