This study was conducted to evaluate the effect of environmental temperature on performance and carcass characteristics of male broilers in the period from 22 to 42 days old. Three hundred and thirty-six male Avian Farm broilers, averaging 624 g were allotted to a randomized experimental design, with four treatments (temperatures of 16, 20, 25 and 32ºC). The treatment 1 consisted of 12 replicates and the others of 24 replicates, all with four birds per experimental unity. The treatments affected weight gain, feed intake and metabolizable energy intake that quadractly increased until the estimated temperatures of 24.4, 19.1 and 19.1ºC, respectively. Feed:gain ratio also changed in a quadratic way, increasing until the estimated temperature of 26.3ºC. The treatments influenced the carcass and breast yield that changed in a linear way as the temperature increased from 16 to 32ºC. Thigh yield changed in a quadratic way, increasing until the estimated temperature of 19.4ºC. The absolute weights of heart, kidney and gizzard and the relative weights of heart and gizzard were affected by the environmental temperatures and were higher in cold environment (16ºC) and smaller in the hot environment (32ºC). The relative weight of kidney linearly increased as the temperature increase from 16 to 32ºC. However, no treatment effect on absolute and relative weights of proventriculus was observed. It was concluded that the best results of weight gain and absolute weights of carcass, breast and thigh are obtained when the birds are reared on environmental temperatures from 22.3 to 24.7ºC. Environmental temperatures bellow or above these values affect negatively weight gain and absolute weights of carcass, breast and thigh.
broiler chicken; carcass; performance; temperature
