Anhidrosis in Horses

Anhidrosis is a fairly common problem for horses in hot and humid regions but there is hope for keeping them in work even without relocating.
Anhidrosis is a condition defined by the decreased ability to sweat in response to an increased body temperature. Its often thought to be intricately tied to high heat but its occurrence is more selective high temperatures must be in conjunction with high humidity.
This condition is cause for concern because between 65 and 70 percent of a horses body heat dissipates from sweating so the inability to cool down can cause a significant impact on health.

Signs of Anhidrosis in Horses
Though horses with anhidrosis are often called nonsweaters this term is misleading The majority of horses with the condition suffer from incomplete or partial anhidrosis meaning they dont sweat as much as they should or they sweat in abnormal patternsnot that they dont sweat at all.
This condition is most often diagnosed in performance horses that are in work but it can affect any horse including those that are retired and not ridden. Studies have shown that darkercolored horses are often more affected by anhidrosis than their lightercolored counterparts1.
This condition doesnt appear on most horse owners radar until their horse has a fairly serious health episode that is linked back to environmental conditions. As temperatures rise horses suffering from anhidrosis may show a decrease in exercise tolerance and a higherthanexpected respiratory rate for the amount of exercise that was undertaken.
These horses may also have dull dry haircoats or be seen leaving the herd to stand in the shade alone. Lack of sweating is the most serious manifestation of the disease and often occurs after other clues are present.
As with many equine diseases its better to catch the condition early when intervention has the greatest chance for impact. Martha Rodgers

VMD owner of Shephard Hill Equine in Lexington Ky. recommends learning your horses sweat patterns in different temperatures especially if hes located in an area with high heat and humidity.
With a noticeable reduction in sweat capability or pattern diagnosing the condition earlier has typically made it easier to stimulate increased sweating with the available treatments Rodgers says. She notes that if the horse has a complete inability to sweat the treatment is often less effective overall or can take much longer to see any effects.
What is the Cause of Anhidrosis in Horses?
The cause of anhidrosis isnt clear but its believed