Oats are considered one of the safest of all grains to feed horses due to their relatively high fiber and low energy content, as it is difficult for horses to consume a large amount. Oats also are less likely to have molds. Oats contain more fiber and less starch than corn. Oats also tend to be higher in protein, lysine, and fat than corn, but like corn, oats have an inverted calcium:phosphorus ratio. Oats are palatable to horses.