The other night, we came home and found one of our chickens dead outside the coop. It looked like she had fallen off the ladder and broke her neck. Today, we found another one, huddled in the corner of the coop, neck twisted backwards dead. I checked her over, and there is no trauma at all. I did notice they have runny poo. Is it wry neck? What do I do for them? Do I need to do anything to the bedding?