I understand that there is a place for commercially prepared chicken rations and Purina is certainly the "go to" brand... but I would like to feed my small flock of older chickens a more natural diet. They free range during the day on acreage - unimproved pasture, vegetable gardens after the produce is picked, weeds and reeds growing around the pond. They have an electric fence and farm dogs to protect them and at night they put themselves to bed in the coop. I supplement their diet with table scraps mixed with egg shells and, since it gets cold here in WA state, I offer them a late afternoon bowl of grain mix as a high calorie treat. I would like an expert's opinion on what the grain mix should consist of or whether these "retired" hens have other nutritional needs. I realize the nutritional needs of 4-5 yr old chickens have probably not been well characterized...