No sweat: Heat, humidity and the problem of anhidrosis in horses

Dr Natalie Novoa showing an acupuncture point for anhidrosis.
Dr Natalie Novoa showing an acupuncture point for anhidrosis. (Photo courtesy Dr Natalia Novoa)

As temperatures rise and summer looms, horse owners must never underestimate how heat and humidity can affect equines. Even during the winter months, it is crucial to monitor how horses react to variations in temperature.

Many problems can arise when temperatures climb, so as a starting point horse owners should pay attention to the amount of sweat their horse is producing. Anhidrosis, or the inability to sweat normally, can be a common challenge, particularly in hot, humid climates, says Dr Natalia Novoa of Florida’s Palm Beach Equine Clinic.

“Anhidrosis can develop acutely but generally develops gradually,” she said.

“Horses lose 65-70% of their body heat through sweating, so the inability to sweat can be a potentially dangerous condition for them.”

In addition to lack of sweat, signs of anhidrosis can include increased respiratory rate, elevated body temperature, areas of hair loss, or dry and flaky skin.

There are several treatment options for anhidrosis including supplements, management changes, and alternative medicine practices.

“Electrolyte supplements and access to salt blocks are important to replenish chloride, sodium, and potassium,” Novoa said. “A Vitamin E supplement can also be beneficial because it is an antioxidant that helps with the oxidative damage due to environmental heat stress.”

In addition to supplements, it is important to keep the horse in a shaded and well-ventilated area if possible. It can also be helpful to keep the horse’s body clipped during the summer season.

Another treatment option is adding one serving of dark beer a day to the horse’s feed. The alcohol in beer is a vasodilator so it helps open capillaries allowing heat to pass through more rapidly to stimulate sweat.

Alternative medicine therapies such as acupuncture can also help decrease symptoms of anhidrosis.

“Acupuncture is very effective at clearing heat,” Novoa said. “The normal functions of sweat glands and sweating are regulated by the heart, the lungs, and the triple heater. Heat and humidity can block the Qi flow of those meridians, which are pathways connecting acupuncture points, leading to anhidrosis.

Dr Natalie Novoa uses Furst Filou, owned by Maura Weis, to demonstrate acupuncture points for Anhidrosis. (Photos courtesy Dr Natalia Novoa)

“Acupuncture treatment strategies are designed to clear the summer heat, nourish the Yin, and promote body fluids. Opening up certain points where the heat tends to collect will help release neurotransmitters that affect the flow of blood and lymph.”

Novoa says there are three areas to work on during the acupuncture process:

  1. Heart: Helps with blood supply
  2. Lung: Controls Wei Qi, which dominates the opening and closing mechanisms of the sweat glands
  3. Triple Heater: Controls pathways of body fluids

“It requires a few acupuncture sessions to see a change. The process is different for each horse. It can also help with symptoms like exercise intolerance, tachypnea, and fatigue.”

Another alternative treatment option is Chinese herbal medicine. New Xiang Ru San powder has proven to be a clinically effective aid for non-sweaters as it promotes heat and fluid disbursement through healthy sweating. It is a blend of the Chinese herbs Bian Dou (hyacinth bean), Xiang Ru (mosla), Hou Po (magnolia bark), Lian Qiao (forsythia), and Jin Yin Hua (honeysuckle flower).

Overall, it is important to manage a horse with anhidrosis carefully. Try to exercise them when temperatures are lower in the early morning or late evening. Also, allow plenty of cool-down time after exercise and monitor their respiration rate.

• Receive a notification when a new article is posted:

Latest research and information from the horse world.

Leave a Reply

Your email address will not be published. Required fields are marked *