Strains of free-range broilers reared in semi-intensive system in a hot climate region

The objective of this work was to evaluate the performance, physiological traits, and behavior of five lines of free-range broilers reared in a semi-intensive system in hot climate region. Four hundred birds, with an initial age of 35 days, were used in five treatments represented by the free-range lines: Pescoco Pelado, Vermelho Pesadao, Carijo, Master Griss, and Colorido lines. A completely randomized design with four replicates and 20 plots was used. Performance (weight gain, feed intake, and feed conversion), rectal temperature, respiratory frequency, and behavior were evaluated. There were no significant differences between the lines for performance and physiological variables. All lines showed thermal discomfort and, based on their behaviors, an adaptation trend to hot climate was noted. The Pescoco Pelado, Vermelho Pesadao, Carijo, Master Griss, and Colorido lines can be reared in semi-intensive systems in hot climate region.