Dietary energy content and floor space relationships for optimal growth and efficiency of broilers

Abstract

Commercial broilers, kept in small, fixed-size pens, were allowed 310, 370, or 460 cm2 of floor space per bird started at one day of age, in a windowless controlled environment house. At each stocking density birds were offered diets with 12.5, 12.9, or 13.4 MJ kg-1 of metabolizable energy from 41 to 64 days of age. Male and female broilers grew more slowly (P < 0.05) when offered the lowest energy diet. They were heavier (P < 0.05) when allowed 460cm2 of floor space per bird. Total output on the basis of liveweight produced per unit of floor space over 64 days of age was largest in the most densely stocked pens. Optimal dietary metabolizable energy concentration was approximately 12.9 MJ kg-1; however, reasons for varying this recommendation are discussed.