Just curious, does free ranging reduce leg problems? (especially using a broody hen so it's a day one free range) I always hear about fast growing meat bird leg problems but not what those problems actually are.
I know sun makes a big difference in vitamin D production and thus calcium absorbtion. Also real exercise helps build better bones and joints in addition to the micro-nutrients in the fresh plant material. The slightly less processed/less-rich diet mix they eat would help any animal.(people too)