My 17yo was on Alfa A oil, Speedibeet and some Barley. He looked in good condition and had enough energy to do the jobs asked of him, without being fizzy. He was on some supplements too. At the time he was out jumping a few times a month.
He's on 16+ at the moment and holds condition well, but i want to make sure he's getting the right nutrients and energy to do the job, he also gets codliver oil for he's joints.