This is to all of you who have or had SLEEPY chickens. I have had the same issue in the past and this is what I have found out. With the last one I had a necropsy done and it showed that it was Arsenic poisoning that killed her, shortly after I found this out a guy from the county came to test my water, I did not know that there was a problem, he said it was being tested because there was high arsenic content and that was the reason the state pays for my reverse osmosis system. I did not know that the state paid for the system I just assumed that the people who owned the property before me put it in, I have since been using the reverse osmosis water for my chickens and no sleepy chickens. The sad thing about is that I was poisoning my own birds and did not even know it, the moral of this story is that if you are having this issue with your chickens please have your water checked (if you are on a well system), Arsenic is naturally occurring in the earth and can contaminate a well at any time.