I'm not sure how chickens are supposed to feel, but when I feel them I can clearly feel the breastbone. They look filled out and fine, but I was always under the impression they should be fuller. At 2 mo. I switched them to grow out feed instead of chick starter because the guy at TSC recommended it to me. Is that the problem? They always have food and water, and I feed them scraps and scratch and worms occasionally. But it seems like they've lost weight since I switched to the grow out feed. I'm not sure though.