Anhydrosis, Dry Coat and Non Sweating Disease, the Puffs

Feeds for Anhydrosis, Dry Coat and Non Sweating, the Puffs in horses

What is Anhydrosis (anhidrosis) in horses

Anhydrosis is known as "dry coat" or "non-sweating disease" and "the puffs". These horses lose the ability to sweat, and hence cannot use evaporation as a form of body temperature regulation, which can lead to overheating (hyperthermia).

How do I know my horse has Anhydrosis

Some horses have been shown to sweat profusely in the few weeks or days before anhydrosis starts. Affected horses can stop sweating altogether, or reduced and patchy sweating, especially in areas typically prone to heavy sweating (such as the girth or over the back). These changes in sweat production can occur overnight or start to set in gradually. Symptoms of anhydrosis include:

  • loss of performance
  • dry coat
  • non sweating

What causes Anhydrosis in horses

The exact cause of anhydrosis is unknown, although it is known that the horse's sweat glands become unresponsive. Horses that are exposed to a hot humid climate are most susceptible to this condition. All breeds of horse can be affected by anhydrosis. One possible cause of anhydrosis is an electrolyte imbalance through osmosis of the blood.

How diet helps Anhydrosis in horses

Anhydrosis cannot be treated effectively through medication and must be managed by diet and controlled environment. Horses that live in a hot humid environment that are not able to make a full recovery should be moved to more climate acceptable regions.

Feeding for Anhydrosis in horses

Feeding low NSC, oil based feeds may  reduce the heat of digestion, and may assist in reducing the cooling requirements of the horse. Oil does not cause production of heat as it is digested and therefore enables the horse to stay cool while feeding and not have to compromise energy levels. Feeds generate heat during digestion in the body, and some feeds generate more heat than others. High fibre diets are digested in the large intestines and generate heat of fermentation. Cereal grains fermentation in the hindgut causes the horse to become hot and "fizzy" which compromises the horse suffering from anhydrosis as they cant cool down.

Balanced electrolyte supplements are available for horses living in hot humid environments and should be fed in the months before the onset of summer/hot weather. Clipping, fan/air conditioning, hosing down and exercising in the coolest part of the day helps.