You shouldn't raise or house turkeys where chickens have been housed. chickens are more resistant to black head and can thus be carriers and infect your turkeys, which are not as resistant. As for ducks, I don't brood or house them with my chicks because ducks are so much messier and will "share the fun" with the chicks. I'd rather clean a smaller duck brooder umpteen times a day than have to clean a much larger one for both chicks and ducks that frequently. My chicks seldom need their brooder cleaned more than once a day, and once they're on pine bedding, it's every other day (my brooder is plenty big enough). Some people brood them together and don't seem to mind the extra mess, but since I usually have several brooders going at once, it's just easier to give the ducks their own space.