The Banes of Bathing Horses

The Banes of Bathing Horses

Minimizing bathing frequency and the use of soaps and potentially harmful chemicals can help improve the overall quality and health of your horse's skin and hair coat.

Photo: Erica Larson, News Editor

Vets examine whether we help or harm horses with frequent lathering and rinsing.

When your gray comes in from the pasture as a bay or your gelding is crusty with sweat and dust after a summer ride, you reach for the hose and bucket. But is your bathing ritual giving him a top-to-bottom gleam … or is it stripping the skin of natural oils and decimating the populations of healthy microorganisms that help fight infection?

“It is amazing how often certain horses get bathed—up to three times a day in some cases, and then they are simply put back in their stalls damp,” says Lori Bidwell, DVM, Dipl. ACVAA, co-owner and founder of Kentucky-based East West Equine Sports Medicine. Bidwell has worked with thousands of performance horses and has pretty much seen it all when it comes to skin issues.

In this article, we’ll learn about the horse’s largest organ system—the skin: what it looks like, what functions it serves, and how daily primping and preening can wreak havoc on this vital structure. 

Skin Deep

You’re likely familiar with the different degrees of burns fire victims sustain. What you might not realize is that these degrees refer to the layer of skin the burn reaches. 

Layer 1: The Epidermis This outermost layer produces and contains specialized skin cells called keratinocytes. They migrate upward from the base of the epidermis, continually replacing sloughed skin cells—much like our fingernails continually grow from near the cuticle and the horse’s hoof grows from the coronary band. Other cells in the epidermis include pigment-producing melanocytes that give skin and hair their color and Langerhans cells that help fight infection, playing an important role in the skin’s immune system. 

Although hairs do indeed pass through the epidermis, the follicles are actually in the layer just beneath, called the dermis. Nonetheless, hairs help protect the skin from ultraviolet light and physical damage (slight abrasions, insects, mild chemicals) and facilitate thermoregulation—cooling and warming by changing their position relative to the skin.   

Layer 2: The Dermis This layer, which makes up the bulk of the organ, contains a variety of structures, including blood vessels, nerves, and “skin appendages.” Its main function is to nurture the epidermis. Blood vessels supply nutrients and help regulate the horse’s body temperature. Specifically, increased blood flow to the vessels in the dermis help dissipate heat during exercise, while blood vessel constriction decreases blood flow to reduce heat loss through the skin. The nerve supply to the skin is impressive, allowing horses to rapidly respond to heat, cold, pain, and subtle pressures and touches. Our nerve supply is similar; think about the immediate reaction you have after touching a dish right out of the oven or slicing your finger on a piece of mail. 

Hair follicles, one of the major skin appendages, produce the individual hairs. Ancillary appendages include sebaceous glands that produce an oily substance called sebum. Sebum protects the skin by keeping it soft, moist, and pliable. It also possesses antimicrobial properties. 

Sweat glands, primarily located on the abdomen and thorax (and not the legs) also help control the horse’s body temperature. As sweat evaporates, the body cools. 

Layer 3:The Hypodermis The third and final layer, found beneath the dermis, contains fat, muscle (the twitch muscles, for example, that discourage insects from landing), blood vessels, and nerves. 

This article continues in the June 2017 issue of The Horse: Your Guide To Equine Health Care. Subscribe now to learn about the skin microbiome, the pros and cons of bathing, and management strategies to keep your horse’s coat shiny and healthy!

About the Author

Stacey Oke, DVM, MSc

Stacey Oke, MSc, DVM, is a practicing veterinarian and freelance medical writer and editor. She is interested in both large and small animals, as well as complementary and alternative medicine. Since 2005, she's worked as a research consultant for nutritional supplement companies, assisted physicians and veterinarians in publishing research articles and textbooks, and written for a number of educational magazines and websites.

Stay on top of the most recent Horse Health news with FREE weekly newsletters from Learn More