Feeding Protein to Performance Horses

Hard-working horses need dietary protein to increase muscle mass, maintain muscle fibers, and repair tissue damage caused by the demands of strenuous exercise.
A research project conducted in Bristol, Virginia, investigated the impact of time of feeding protein prior to exercise. Researchers concluded that when protein-rich feeds are offered an hour before exercise, the amino acid levels in the blood will be adequate to support muscle protein synthesis in the important time span of two to three hours post-exercise.

It’s tempting to think that if a little protein is good, more must be better, but this is not the case for horse feeds. First, feeds that oversupply protein are not economical because protein is a relatively expensive feed component, and feeding more than a horse’s requirement is an unnecessary expenditure. Second, when horses consume more protein than they need, the unused protein is excreted from the body in sweat, feces, and urea-rich urine, which can be converted to ammonia by bacteria. Ammonia fumes degrade air quality in a stable, acting as an irritant and possibly affecting respiratory health.

So how does an owner know how much protein to feed a particular horse? Each horse’s requirement and usage will be slightly different depending on metabolism, age, and level of exercise, but the bottom line is that most of the better commercial feeds designed for active horses contain plenty of protein to meet these requirements, when fed in combination with an appropriate amount of forage, without providing significant excesses.