Looking for horse tack or a horse feed containing grain only in Ohio? For example, it takes 42 lbs of oats to provide the amount of nutrition found on most quality feed concentrates. Oats contain a very high level of non-structural carbohydrates, and an inverted calcium-phosphorus ratio. Horses need twice as much calcium as phosphorus, cut oats have five times as much phosphorus as calcium. Contact your feed specialist to find the right grain for your horse.