Okay, all of my chickens feel boney. I haven't had them for long. A friend of mine told me to just feed my chickens cracked corn in the winter and in the spring, summer and fall to feed them layer mash mixed with cracked corn. All of my chickens get unlimited cracked corn. They also get rabbit pellets, not much, but as a treat. My friend said if you can feel the breast bone easily that means your chickens are too thin. You can feel it on all of mine. What am I doing wrong ?