I`ve had black head a couple of times with the turkeys. I read on here, and I don`t know if this is true on not.... but if they get it, and are successfully treated 3 different times they get more or less immune to it. Not sure if thats true. I have 30 acres, the turkeys sleep in the barn wherever they want at night. Chickens are locked in their coup at night, but all free range where they want. The turkeys actually grew up with those chickens pictured and they are all exactly the same age. Right now they have been black head free for quite a few weeks. So i am keeping my fingers crossed that they are not going to get it again. But if they do they are so easy to medicate, just a simple pill in the mouth, once a day for 5 days and its over. Then they get a regular worming. I know what to look for and I look at their poop every single day. So far so good. I love my birds.