We've had turkeys/ducks/and chickens for over a year now. They all have separate coops, but they are all under one roof. They have their own housing, and they do not go into each other's coops. Granted, our turkeys only hang out with us for about 9 months (because they are for meat), our chickens are for eggs, and or ducks are for slug control and eggs. No problems that I know of, other than aggression issues. This is the first year we've let everything free range all together. Occasionally one of the feisty chickens will get into it with a turkey, and I do intervene. The turkeys could do some damage. (we have bronze turkeys) I don't think I was ever told about "blackheads disease". I know I wasn't supposed to house them when they were chicks. Just make sure they have a lot of space.