Factors Affecting the Metabolizable Energy Content of Poultry Feeds

EVIDENCE is accumulating which demonstrates that the metabolizable energy (M.E.) content of poultry feed ingredients may vary according to the nature of the materials with which they are combined. The M.E. value of a sample of corn varied when the basal diet, with which it was combined, was changed (Sibbald et al., 1959, 1960a). A study of the M.E. content of tallow and undegummed soybean oil demonstrated that increased use was made of the energy of tallow when fed in conjunction with undegummed soybean oil; it was also reported that the levels of both protein and fat in the diets significantly influenced the M.E. values of the fats (Sibbald et al. 1960b, 1961a). The dilution of a chick starter diet with either cellulose or kaolin may allow increased utilization of the energy contained therein (Sibbald et al. 1961b). Baldini (1960) reported that chicks metabolized more energy from a methionine-deficient diet…