Feeding a horse may appear easy, but you would be amazed if you knew about the ignorance level of various horse owners. It is a fact that there is no golden rule relevant involving the nutritional needs of a horse, as it mostly depends on the age, body weight and the level of activity, which the horse goes through. Grass is the most fundamental part of a horse diet. It is one of the MAJOR necessities for a properly functioning digestive system so when we speak of forage, we normally mean natural pasture and cut hay.