When we left this morning all 16 chickens were fine. This afternoon we returned home to find one of our Buttercups dead by the coop door. No signs of injury and did not notice any problems this morning. About a week ago we treated the droppings in the roost with lime, could this have caused any problems. It was a lite treating, just trying to take out some moisture out and smell down. Is it possible she just flew into the door or is there some other hidden issue. Everyone else seems just fine. We have also been feeding oyster shell with laying mash and cracked corn, been doing this for three months. What Happened?