How much corn is in cattle feed?

It depends on the location, and the type or class of animals fed. There can be as little as no corn (0%) in a feed ration for cattle, or as much as 85% in a feed ration. Not all areas in the world can or will grow corn, and not all feed fed to cattle includes corn. For instance, much of the grain fed to cattle in Canada is barley or oats, not corn.