Tonight when I went to feed my horses and close up the chickens I found one of my hens laying on the stall floor with her head flopped to the side and her beak buried in the shavings. For all the world she looked dead. I tried to roll her to make sure she was dead and she jumped straight up, pointed her beak at the ceiling and with it wide open started making a noise I can only describe as screaming, not even close to any chicken sound I've ever heard. It went on for approximately 30 second then she stopped. I picked her up and examined her but the only sign of injury that I could find was about 1/3 of her wing feathers are missing from her left wing although she does seem mildly sore. I checked all her bones and ran my fingers through her feathers to see if I could find a hidden wound. I'm thinking that something tried to get her during the day (they're all free-range), scared her half to death, literally, and that she went into shock. Has anyone else ever run into this screaming sound and this seeming in-shock behavior? By the way, I put her on a low perch and she was able to jump up to the higher one with the other chickens with no problem.