I dont know why,or how. We have a large run fenced off with chicken wire ,,top also. Dont see a sign of a break-in. It had no neck feathers and was bare to the neck bones. Will the others chickens do this?? My GF fed and watered the chickens the last 2 days and didnt look the run over very good so it may have been laying there dead for that time,,we really dont know. She knows now,, to look it over well for issues. I really need to know if I have a predator or if the other chickens will eat the dead one like this. I think it died,,somehow??? And the other birds did this,,, but I could be wrong.