Horse Anhidrosis Heat Management

Anhidrosis (inability to sweat) is a serious condition affecting horses in hot humid climates. Management including cooling strategies and environmental modification are essential for affected horses.

Key Facts

Anhidrosis affects horses relocated to hot humid climates and can develop in horses already living in such regions
Without sweating, horses cannot thermoregulate effectively making exercise and heat exposure dangerous
Affected horses show dry skin, elevated respiratory rate and rapid overheating during exercise
Moving affected horses to cooler regions typically resolves the condition over several months
Management strategies include exercising only in cool periods, fans, cold water hosing and air-conditioned stabling

Welfare Considerations

Horses with anhidrosis are at genuine risk of life-threatening heat stroke during exercise in warm conditions. The inability to sweat is not immediately obvious making accidental overheating a significant welfare risk. Owners in subtropical and tropical regions should be aware of anhidrosis as a possible cause when horses show poor performance and elevated breathing rates in warm weather. Affected horses require significant management modification.

What You Can Do

Exercise anhidrotic horses only in the early morning or evening when temperatures are lowest
Apply cold water frequently during and after exercise to provide external cooling
Install fans in stabling and provide maximum shade during hot periods
Consult a vet about electrolyte supplementation and the limited evidence base for anhidrosis treatments
Consider relocating severely affected horses to cooler climates if welfare cannot be maintained locally