Percentage Utilization and Supplementary Relationships of Certain Protein Concentrates in Semi-Purified Basal Diets for Growing Chickens

RELATIVELY little information is available on the nutritive value of protein in protein-rich feeds when fed singly and in combination as practically the sole source of protein in the diet of growing chickens. In the case of rats, fundamental studies on protein have led to many important discoveries with regard to the essential and non-essential amino acids required for maintenance and growth. Biological values also have been determined with rats in evaluating many of the proteins from single sources as well as their supplementary values when fed in various combinations. Recent information reviewed by Almquist (1941) indicates that the amino acid requirements of the chick may be different from those of the rat and that data obtained in the evaluation of protein with rats cannot be applied unqualifiedly to the chick. The lack of fundamental knowledge on the nutritive value of proteins for chickens is due partly to the lack . . .