Their internal body temperature can reach 105 degrees during intense work on a hot day. Heat stress is more a problem in humid parts of the state, Householder adds. Horse experts do offer some feeding and management tips to minimize the impact of heat stress on horses. The horse's body produces heat when it rids itself of protein that can't be utilized. Mature performance horses should get a ration with about 10 percent crude protein in the total ration.
Digestion produces heat, but fat-supplemented feed generates less heat than fibrous feeds.
Research shows that horses fed higher-fat feeds, or those with more than 3 percent fat, require less feed to perform the same amount of work. Microbial fermentation of hay produces heat, so feed a small amount of hay in late morning and the larger portion at night when the weather is cooler. Fatter horses require more energy to dissipate heat and cool themselves than thinner horses. Horses that are too thin don't have the energy reserves needed for hard work. A condition score of five, where the horses ribs can be felt but not seen, is the best compromise between energy storage and fat cover.