My 2 year-old, 7 pounds, standard silver-laced Cochin hen is sick. She is standing still, she doesn't want to go outside. She hasn't been roosting for the past 3 nights, and this morning she was moving very slowly. All the other chickens are energetic, and lively, she has lost some weight during the past 2-3 days. We checked her for any signs of bleeding, she didn't have any near her bottom. She has normal poop. We have given her water that had nutri-drench in it, also some strawberries. She hasn't eaten or drunk much either. We need some help figuring out what is wrong with her.