The natural capability of sweating by cattle gives them an edge over swine and poultry to rid of their body heat in the hot and dry conditions. By the same token, increase in relative humidity during hot weather will put cattle under stress much faster than for pigs or chickens. - See more at: file:///C:/Users/Nutthapon/Desktop/Heat%20Stress%20Index%20Chart%20for%20Swine%20Producers%20-%20The%20Pig%20Site.html#sthash.VDGfE3Ve.dpuf