Can I let my chickens eat DUCK egg shells? They all share the same area. I used to bake my chicken egg shells, and crush them to put them in their food. That's just too much work. So, lately, I've just tossed them in the grass, and step on them so they are broken. EVERYONE eats the chicken egg shells----turkeys, ducks, and chickens. So why couldn't I feed them duck egg shells the same way?