Poultry feeds are supposedly formulated to provide a complete diet for the specific birds they are blended for, but i have reared chicken chicks well on partridge crumbs/Pellets , fed Pheasant breeder pellets to adult Chickens, and on the other foot reared healthy Pheasants on Poultry crumbs and growers Pellets! So I can't imagine there will be too much problem. Although I would keep an eye on the birds development.