Heart disease, or cardiovascular disease, is a general name for a wide variety of diseases, disorders and conditions that affect the heart and blood vessels. Heart disease is the number one cause of death in the United States, according to the Centers for Disease Control and Prevention (Source: CDC).
Mostly sheep eat grass, clover, forbs, and other pasture plants. They especially love forbs. In fact, it is usually their first choice of food in a pasture. A forb is a broad-leaf plant other than grass. It is a flowering plant. Forbs are often very nutritious.
You CAN feed your horse just hay, but you have to up the portions and it also depends upon the type of hay you are feeding. Alfalfa mix is normally the best but there again, you're goinng to have to feed more hay to make up for the not feeding grain when you are riding.