Do your chickens free range or pasture? Laying crumbles and small amounts of corn should be fine, and you can also feed scraps from the kitchen. The primary things you need to be sure to address when feeding laying/breeding chickens is that they have good protein content in the food you feed, and that they have access to unlimited calcium supplies like oyster shell. Be sure your chickens also have grit if they aren't free range. My chickens are free range, so I don't heavily feed laying crumbles, and corn is ALWAYS treat only. The whole flock never gets more than 2 scoops a day, and I have 13 chickens. I haven't hatched any of my fertile eggs yet, but I have good strong shells on all our eggs.