I keep the corn and barley in and just add the SRB as a supplement basically. Corn, Barley, Rice, Oats are all grains. So what you get from all of them is basically the same, starch. Which their body converts to energy, and the body stores energy as fat. The difference in the grains comes in how many kilocalories of energy they contain and how easy they are to break down. You wouldnt want to remove the corn and barley from the diet because you would break the bank trying to balance the diet with SRB. We keep corn in there to provide most of the energy they need because corn is the cheapest, then we add the barley and SRB as a supplement to boost it because they are more expensive.