An experiment was conducted to evaluate the effect of starter and grower diets duration time involving 240 broiler chicks (Ross 308) grown to 42 days. A practical starter diet, containing 22.2% protein and 2910 kcalME/kg was fed for 7, 14 or 21 days. Either a grower diet containing 20.3% protein and 3075 kcalME/kg was fed for the remainder of the growing period. A finisher diet with 18.4% protein and 3125 kcalME/kg was fed from 35 to 42 days of age. Each of treatments was replicated in four floor pens of 20 birds each. The days of diets change had not significant effect on body weight at 21 and 42 days. Changing time of diet did not show any significant effect on feed intake and feed conversion ratio from 1-21 days of age. Abdominal fat percentage was similar in all experimental groups. There were no significant differences (p<0.05) between treatments in breast meat weight, tibia weight, gizzard weight and liver weight as a percentage of body weight. We conclude from this study that given typical cost difference among starter and grower diets, changing diets at earlier age may have considerable economic impact on broiler production. The results suggest that broilers fed a starter diet containing above mentioned nutrients for 7 d, may meet the production constraints
