How horses manage body temperature, the welfare challenges of heat and cold stress in managed settings, and evidence-based strategies for climate management in different environments.
Equine thermoregulatory welfare is complicated by the frequent misalignment between owner intuition about temperature comfort and equine physiological reality. Horses are much better adapted to cold than most owners appreciate — their efficient metabolic heat generation, winter coat capacity, and fat reserves allow unclipped horses in good body condition to tolerate temperatures far below freezing without welfare compromise, provided they have shelter from wind and rain. Over-rugging — the excessive application of heavy rugs in mild weather — is one of the most common equine welfare problems in temperate climates, causing sweating, skin disease, and metabolic disruption through suppressed thermoregulation. In contrast, hot climate management requires attention to shade availability, air movement, access to water, and exercise timing to prevent heat stress. Anhidrosis — the inability to sweat effectively — is a significant welfare problem in horses relocated to hot humid climates or in genetically predisposed individuals, requiring careful climate management and veterinary intervention. Understanding equine thermoregulation accurately, rather than projecting human cold sensitivity onto horses, is a prerequisite for appropriate welfare management.