The Relation of Breed and Sex of Chickens to the Utilization of Energy

Abstract

IN conducting nutritional studies, especially those concerned with energy metabolism, it is desirable to know the variation in nutrient utilization that can be attributed to the breed and sex of the birds used.The literature pertaining to differences in nutrient utilization, reviewed by Hutt (1964) and Sibbald and Slinger (1963b), indicates variations among breeds, strains and sexes in their nutritive requirements. These differences have been attributed to genetic and physiological variation.Specific breed differences in energy requirement and nutritive utilization have been reported by Shellenberger et al. (1960) and O’Neil et al. (1962). Sibbald and Slinger (1963b) and Slinger et al. (1964) have demonstrated that White Leghorn chicks metabolize more energy per unit of feed than do either White Plymouth Rock or commercial broiler cross chicks.A preliminary trial involving duplicate groups of male chicks of a New Hampshire X Silver Cornish cross and of a commercial incrossbred line, both …