Thoroughbred horse, breed of light horse more properly known as the English running horse. As its name implies, it was the first pedigreed, or "thoroughbred" horse. It originated in England from crosses between imported Turkish and Arabian horses and existing English lines and has since been exported around the world
If you do feed a concentrate ration to your horse, avoid straight cereal grains like oats, corn, or barley, and make sure each feeding is accompanied by as much forage as possible. A minimum of 70 percent of a horse's daily calories should come from hay or pasture.