It depends on what they ingest on range that has nutritional value. Mine range an hour or more a day when I'm home. I rotate between 2 flocks. The way I see it, so long as my birds have good appetites, are at a good weight, have tight droppings, have glossy feathers, and have bright red combs, they are not bearing any nutritional deficiency or disease. I feed a 17% layer ration, a 15% scratch/pellet mixture as a treat, and supply granite grit and oyster shell. I try to supplement a milk protein in feed once a week (usually 1% buttermilk, goat or sheep milk). I don't have digestion issues doing it that way, though I'd recommend doing scant amounts in the beginning when introducing it to diet. I supplement water with vitamins 2-3 times a week, and Probiotic soluble in waterers once a week. I change things up with supplementation depending on time of year, whether or not they are in moult, breeding season, or depending on what I witness in appearance and activity. I handle them regularly to look their bodies over when on the roosts at night.
