we feed layer mash, if you are not butchering them, it should be enough to keep them healthy, they do make game bird feed, or a higher protien feed. We feed layer because our chickens and guineas and turkeys and ducks all run together.
Mine do best on Turkey Starter (30%). I do give them turkey breeder (20%) and then back to turkey starter (30%) to get them laying good. Mine seem to stay in laying longer this way.