EFFECTS OF FEEDING LOW-PROTEIN GROWER DIETS ON PERFORMANCE, CARCASS CHARACTERISTICS AND ECONOMIC EFFICIENCY OF BROILER CHICKENS

A total number of 120 unsexed one-day old of Cobb 500 broiler chicks were distributed into 4 treatments (30 birds each), used for evaluated the grower diets contain different levels of protein, on growth performance, carcass characteristics, and economic efficiency. The experiment lasted from one to 42day-old and contained 4 treatments diets (starter and grower) that T1(100-100); contains 100% protein requirements of the strain according to the breed manual at starter and grower period, T2(100-95%), T3(100-90%), and T4(100-85%). Results of These treatments showed that, feeding 100%, 95% and 90% protein requirements were higher insignificant records (LBW) and (DWG) than feeding 85% of protein requirement after 6 weeks from hatching. Feed consumption and Feed conversion ratio during overall six weeks from hatching until marketing weight was non-significant different among all treatments. Concerning carcass traits, Treatments T1 and T2 had higher (P<0.05) values of dressing percent than all other treatments. Decreasing dietary CP generally tended to increase the relative weights of the giblets, although such increases were not significant. The economic study indicated that birds fed on T2, and T3 levels of protein diets treatments were the most profitable diet among experimental diets. These results are due to feed intake and average body weight gain data which reflect on net return/bird. It is mean that decreasing the gap level of protein from starter period to grower period lead to positive effects on most of parameters which estimate the performance and production which reflect on economic efficiency of broiler chicks' strategies production