Efeito do ambiente térmico sobre a temperatura média corporal de frangos de corte dos 22 aos 42 dias de idade

The Brazilian tropical climate is characterized by high values of temperature and relative humidity, especially in summer conditions and can lead to thermal discomfort, causing considerable economic losses, reduced animal performance and increased mortality of animals. The objective of this work was to study the influence of different levels of cyclic heat stress environment, including ranges of comfort (25°C), heat stress mild (28°C), heat moderate (31°C), heat high (34°C) and heat severe (37°C), on the performance of broilers in the late growth phase ( 22-42 days) , housed in climatic chambers of Research in Ambience (AMBIAGRO) , Department of Agricultural Engineering , Federal University of Viçosa MG. Birds kept in treating heat mild (28°C) , considered by literature as 1099 causer heat stress , obtained a better performance than those exposed to other situations , indicating that this would be the temperature ambient desired for the broilers in their finals phase.