| This study aimed to assess the influence of thermal conditioning during the first week, and to verify the effect of this, upon the heat challenge by the end of the productive period on performance, heart morphology and carcass yield. A total of 980 Ross male broiler chicks randomly assigned according to a completely randomized design with 4 treatment and 8 replications totaling 32 experimental units. The treatments consisted of different temperature ranges in the first week of life: thermal comfort temperature, temperature below the comfort zone, temperature above the comfort zone and thermal oscillation. At 35 days of age four replicates of each treatment were submitted or not to heat stress in last week's rearing (27 and 32°C). Animals submitted to... |
