There aren't any grains that provide a perfect ration for livestock by themselves. Any grain that you look at will have certain nutrients and be lacking in others. That is why livestock rations are a mix of grains. A certain amount of this, a certain amount of that will provide a complete ration appropriate for the type, breed, age, production level of any given animal.
To say that corn is just filler because it is relatively low in protein and lacking in certain amino acids is way off base. Most grains are lacking those same amino acids, they just aren't common in plant based protein.
Bantiesrule, don't worry about it too much. Birds are capable of self choice to provide for their needs. If they need what is in the layer feed they will eat it. If they need the energy in corn they will eat it. Although the layer ration should have everything they need, providing a variety is probably better for them than forcing them to eat the layer ration.
To say that corn is just filler because it is relatively low in protein and lacking in certain amino acids is way off base. Most grains are lacking those same amino acids, they just aren't common in plant based protein.
Bantiesrule, don't worry about it too much. Birds are capable of self choice to provide for their needs. If they need what is in the layer feed they will eat it. If they need the energy in corn they will eat it. Although the layer ration should have everything they need, providing a variety is probably better for them than forcing them to eat the layer ration.