We have kept turkeys, hens, geese and ducks for years, all roam together but are housed separately every night. Never had any problems apart from some fighting with the males. All get different food and all get drinking water with Apple Cider Vinegar mixed in. This is supposed to alter PH level in gut and stop worm infestations, Never had Blackhead or any other disease for that matter Maybe we are just lucky but most of the hens and geese are over 12 years old.