Heat stress is one of the most significant but under-recognized welfare problems affecting cattle in many production systems.
Heat stress causes significant suffering in cattle — rapid breathing, lethargy, crowding around water sources and in extreme cases, death. Dairy cows with their high metabolic rate from milk production are especially vulnerable. Climate change is increasing both the frequency and intensity of heat events that push cattle into heat stress. Provision of shade and water is the minimum welfare standard; cooling systems provide additional protection for high-producing dairy cattle.