Two experiments, with 288 and 196 birds, half males and half females, respectively, were carried out to determine the copper (Cu) requirements for broilers in the growing (from 22 to 42 days) and finishing (from 43 to 54 days) phases. Two basal diets were formulated to meet the bird nutritional requirements, except for Cu, that was deficient at the levels of 1.40 and 1.33 ppm, respectively. The treatments of both experiments consisted of the Cu supplementation levels, from Cu sulfate, resulting in a total of 1.40, 4.90, 8.40, 11.90, 15.40 and 18.90 ppm Cu in the diet for the growing of phase and 1.33, 4.83, 8.33, 11.83, 15.33 and 18.33 ppm Cu in the finishing phase. Average weight gain, feed intake, feed:gain ratio and Cu concentration in the bone, liver and serum were the evaluated variables. Copper levels, in the both phases, did not affect bird performance and Cu concentration in the bone. However, effect on the Cu concentration in the liver and serum was observed in the growing phase. In the finishing phase, Cu levels affected only Cu concentration in the liver. In the growing phase, was choosen the requirement value estimated by the variable Cu concentration in the serum, which was 11.1 ppm. In the finishing phase, levels of 8.5 to 11 ppm, commonly present in corn and soybean meal based diets, are adequate to animal performance.
requirement; liver; mineral; bone; serum
