Effect of iso-energetic exchange of dietary fat and starch on growth performance and body composition of broilers: Experiment 1

Dietary factors such as the concentrations of protein/amino acids, fat, and starch + sugar and their ratio, may affect the post-absorptive metabolism of energy and protein and energy deposition in the body. In a 2x2 factorial design, the effects of two dietary crude protein (high protein (HP) vs. low protein (LP) concentrations; 200/190 vs. 170/160 g/kg in grower and finisher phase) and two dietary fat/starch concentrations; (high fat (HF); fat and starch 105 and 340 g/kg, respectively) and (low fat (LF); fat and starch 65 and 420 g/kg, respectively) on growth performance and body composition of Ross 308 broilers were studied (9 to 35 d). From this experiment it can be concluded that dietary energy source and protein level in iso-energetic diets, balanced for first limiting essential amino acids, influence growth performance and body composition of broilers.