Vegetable oil helps in digestion and is responsible for smooth muscles and joints in horses. It adds more shine and gloss in their fur. Vegetable oil is a good horse source of energy. Compared to cereals, vegetable oil contains two to three times the amount of energy. The energy of vegetable oil is slowly released and is hence also slowly available. Vegetable oil can be called a safe thickener for horses. Vegetable Oil only contains energy and fewer nutrients.