Innovative Ways to Keep Dairy Animals Cool During Heat Stress-A Review

High producing dairy animals dissipate heat by metabolic processes and the heat production increases as the animal's body weight and level of milk production increases. If the ambient temperature is high, the animal is not able to dissipate the heat produced. Therefore it is necessary to find effective methods to alleviate heat stress. The most common way to cool dairy animals and their environment is by evaporative cooling. In a tropical climate with high temperatures combined with high humidity, cooling with evaporative systems is limited. In those conditions, methods that are beneficial to the animal's natural mechanism of heat loss are preferable. Any cooling system that is to be effective must take into consideration the intensity of solar radiation, high ambient temperature, and the high relative humidity, which increases to almost saturation during hot-humid season.