Interrelationships among Dietary Energy, Protein, and Amino Acids for Chickens

Abstract

THE economical availability of fats for animal feeding made it possible to increase the energy content of poultry rations. Scott et al. (1947) had reported that rations high in energy content promoted more rapid growth and better feed efficiency in chickens than those of lower energy. Henderson and Irwin (1940) reported that up to 10 percent of soybean oil could be fed to chicks without affecting the rate of growth to eight weeks of age. Greater amounts resulted in deleterious effects. More recent workers (Siedler and Schweigert, 1953; Sunde, 1954; Runnels, 1954; and Donaldson et al., 1954) reported improvements in feed efficiency but not in growth rate. On the other hand, substantial chick growth improvements were noted by other workers (Robertson et al., 1948; Kummerow, 1949; Carver and Johnson, 1953; Pepper et al., 1953; Yacowitz, 1953; Yacowitz and Chamberlin, 1954; and Donaldson et al., 1956) with additions of fat to …