I have narrowed down the issue to wry neck, coccidiosis (sp?) Or mereks. Although i dont think that is what it was. I came home and found one of my young pullets in the run puffed in a ball shivering. I thought she got cold since it was sleeting so i brought her inside in a tote. I let her warm up and noticed her stool was yellow and very watery. Tried to get her to drink but she wouldn't. I even tried with a dropper and she just let tbe water run out of her beak. I did notice she seemed a little off balance and couldnt get up with out assistance. I monitored her and she started to go down hill fast. I have never seen a chicken decline so fast. Within 1hr she started shrieking and flopping around. I got her calm. After about 5 min she started to have a tick in her head then she would rear her head back over the top of her body and flap frantically. It was almost like she was having a sezure. Shortly after this i made the tough decision to put her down and end the suffering. She passed while i was walking out to put her down. All of this happened with in 2 hrs of finding her. She was fine up to that point no sign of illness. Now i am worried about my other chickens. No one is showing signs of issues. Anyone have any ideas what would cause such a violent and sudden death? Thank you in advance.