Effects of decreasing dietary crude protein levels on the growth performance, carcass quality and meat quality of broiler chickens

The objective of this study was to determine the effects of decreasing crude protein in the broiler diet on the performance and carcass composition of broiler chickens. In the experiments, 128 male Arber Acres (15 days old) were divided into 4 different protein groups (21.50, 20.50, 19.50 and 18.50%). All the treatments were isoenergetic at 3,150 kcal/kg. Water was supplied ad libitum for broilers in the different dietary treatments. The experiment lasted for 42 days. The results revealed that the body weight, weight gain and ADG of T1, T2 and T3 were greater than those of T4, whereas the feed intake decreased when the birds were fed T4. The edible meat yield, with the exception of that of the breast, wing and back, was not significantly influenced by the experimental diets, whereas the breast percentage decreased with decreasing levels of protein in the diet. Moreover, overall meat traits did not differ. The results of this study suggest that consuming more than 19.50% crude protein in the diet has no negative effect on performance or carcass or meat traits.