We have acres of good mixed pasture and our chickens are out and about most of the day. They range free and will be moved with their night shelter throughout the summer to fresh grazing areas. No pesticides are used, so there's a natural amount of bugs and worms around. There is also commercial feed available at all times. They haven't been eating nearly as much commercial feed lately, which isn't surprising, and I know they should instinctively eat as much of it as they need. I keep reading that chickens can't remain healthy by foraging alone, but have not found any concrete information (like a recent scientific study) on what it is they need as a supplement. Does anyone know what it is exactly that free-ranging pastured chickens should be getting from commercial feed or from farm produce, grains, seeds, etc.?