Thermal comfort indices applied to livestock

Abstract

Exchanges of heat between the animals and the environment depend on physiological factors and environmental aspects that are related to complex and varied. An animal suffer heat stress when it produces more heat than it can dissipate. To fit, he is forced to reduce consumption of foods and their production necessarily declines. In tropical solar radiation is of high magnitude and the mean temperature of the heating environment during the day is usually much higher than that of air, and the ability to handle animals depends on certain physical characteristics. There are several indexes whose primary goal is to determine the suitability of an environment with respect to an activity or a specific type of animal. These indices can hardly be widely used, since they are structured on the basis of certain environmental factors, that may be important in some animals and not for others. Furthermore, some indices are based on specific associations of environmental factors that occur in certain places.