Effect of dietary energy concentration on the performance of broilers.

The effect of varying ME content between 11,5 and 14,2 MJ/kg feed was studied with broilers in an 8-week trial. Ten treatments were used with dietary ME levels of 11,5; 11,7; 11,8; 12,1; 12,2; 12,5; 12,9; 13,2; 13,4 and 14,2 MJ/kg feed. Rate of gain and efficiency of feed utilization in terms of g feed/g gain were better on the higher energy levels. The response was linear. Feed intake, in terms of g feed, was linearly but negatively associated with energy level but constant in terms of KJ ME intake. Efficiency of feed utilization in terms of KJ ME intake/g gain also approached constancy. Values of 1050 KJ ME/day and 30 KJ ME/g mass gain appear to apply within a fairly wide range of dietary energy concentrations and consequently may be used in production prediction models. It should be economical to use cheaper low-energy content feedstuffs, such as sunflower oilcake and wheaten bran, in broiler diets provided fibre specifications are met.