EVALUATING SUMMER WEATHER CONDITIONS FOR HORSES

Dr. Cynthia McCall
Extension Horse Specialist
Alabama Cooperative Extension System

     A rule of thumb for determining whether or not a horse should be worked is to add the temperature (in degrees Fahrenheit) and the relative humidity (%). If the total of these numbers is below 150, most moderately fit horses easily can cope with moderate work. A total between 150 and 170 may indicate weather conditions where the horse cannot cool its body easily during work, and the horse should be worked only if needed. A total between 170 and 180 indicates weather conditions that easily can result in an overheated horse. Riders should carefully and frequently monitor their horse’s well-being if they must ride them in these weather conditions. Hot, humid weather conditions resulting in a number over 180 result in a very dangerous situation for the horse, and riders definitely should stay off the horse during these conditions.

     To help horses stay cool, horse owners should provide shade for their animals, give the horse unlimited access to clean, cool water (unless the horse is hot from exercise or very thirsty), and work the horse only during early morning or late evening hours when temperatures are cooler. Providing a trace mineral salt block will help the horse replace electrolytes lost through sweating. Horse owners also can sponge or hose their horses with cool water to make them more comfortable in the heat. Scraping excess water off the horse after hosing or sponging allows evaporative cooling to occur which is very effective at removing body heat. Horse owners should be cautious when trailering horses and confining horses to stalls because poor ventilation can result in dangerously hot conditions in both trailers and stalls.