Growth performance and carcass characteristics of broilers fed diets varying in supplemental copper concentrations from 29 to 53 days of age1

High concentrations of dietary Cu have been shown to improve growth performance of broilers raised without antibiotics. A study was conducted to evaluate the effects of feeding high concentrations of dietary Cu to male broilers from 29 to 53 D of age. Broilers received common diets containing 135 mg/kg of supplemental Cu until 28 D of age. During the finisher 1 (29–40 D of age) and finisher 2 (41–53 D of age) phases, broilers received 1 of 5 treatments. These 5 dietary treatments were formulated at 0-0, 135-0, 270-0, 135-135, or 270-270 mg/kg of supplemental Cu in the finisher 1 and finisher 2 periods, respectively. At 54 D of age, 14 birds per pen were processed and were front-half deboned to determine breast meat weights and yields and evaluated for breast meat quality defects. No significant differences were observed for growth performance characteristics because of high variance in BW gain and feed conversion ratio. Broilers fed 270-270 mg/kg of Cu diets had higher total breast yield than the broilers fed no supplemental Cu from 29 to 53 D of age (28.1% vs. 27.6%). Severity of white striping or wooden breast was not affected by Cu treatment. These data indicate that high concentrations of dietary Cu may increase breast meat weight and yield of broilers processed at 54 D of age with no adverse effects on meat quality.