How Much Dietary Energy Is Needed by Exercising Horses?

This study was conducted to measure the amount of energy expended by horses traveling at speeds up to 400 m/minute on a racetrack both with and without a rider, and to attempt to use these data to formulate feeding standards for horses performing submaximal exercise.

Four gelding were used in the study. The horses exercised on a track, both with and without a rider, and expired air was collected using a face-mask that allowed energy expenditure to be measured with a mobile modified open circuit indirect respiration calorimeter.

For all horses, more energy was expended when horses carried a rider. The amount of energy was related to speed and was also proportional to the body weight of the animal or the combined weight of the horse and rider. Fat is known to be the primary substrate for energy generation in horses during low intensity work. Using a value of 55 to 60% for the efficiency of utilization of digestible energy for submaximal work, these values can be used with a supplied equation to calculate the additional amount of digestible energy needed by horses working at this level.

This report of research conducted in 1985 by Joe D. Pagan and coworkers was published in Proceedings of the 9th Equine Nutrition and Physiology Society Symposium.

Read the entire research paper, titled Energy Expenditure in Horses During Submaximal Exercise.