Sharon Spier, DVM, PhD, DACVIM, Professor Emeritus Medicine & Epidemiology, University of California, Davis, and the Internal Medicine specialist working at the WEG Tryon 2018 Equine Hospital, has dealt with the effects of heat and humidity on horses in many competitions over her career. We asked her for her top tips on managing horses in hot and humid weather. Following are some basic recommendations from Spier.
1. Know your horse. You need to know the horse’s ethogram, which is a term that means knowing all of the different kinds of behavior or activity observed in a particular animal. Know his attitudes. Know his outward behavior, from his eyes to the crinkle in his nose when he is unhappy to his head carriage. Know his water and feed consumption. Know his manure. Know his appetite. Know his normal respiratory rate. Know his normal body temperature and use a rectal thermometer to check it regularly.
2. Water. Make sure your horse is drinking, especially if he is also traveling in heat and humidity. “Staying hydrated helps a horse cope with heat,” said Spier. Don’t just have a bucket of water, have several buckets of water. Have a clean muck tub of water. Have a clean trash can of water. Encourage water intake. Some horses don’t drink unfamiliar water as well as they do water at home. “At WEG, some people were catching rain water, and it worked,” said Spier. You can feed haylage. Spier said you can make “sweet tea” of water with a little sweet feed in it for flavor.
3. Provide electrolytes and salt. Make sure you are providing salt and electrolytes to replace the minerals (particularly sodium, chloride, potassium, calcium and magnesium) that are lost when horses sweat. You can use table salt or lite salt offered loose, said Spier. She said a product that was well-researched and used at the hot and humid Atlanta Olympics was Summer Games.
4. Help horses lose heat. Evaporation of sweat is an important part of the cooling process. It can become too humid for a horse’s sweat to evaporate properly (if the heat index, or the combination of heat and humidity is greater than 150, it means heat loss via sweat is ineffective). To improve heat dissipation in horses, you can use fans, misting fans, and cold water put on the horse and scraped off as starting points.
5. Be aware of the environment. Pay attention to air exchanges in a barn to help keep hot air rising and cool air entering the building. Be aware of where the sun hits the stable and accommodate horses that are on the “sunny” side of the barn on a hot, humid day. Understand that lighter colors are better than darker colors if you must use a cooler, and use coolers sparingly.
Health information from WEG Tryon 2018 is brought to you by KindredBio Equine.
