3 days or so ago we bought four yearling chickens from a local hatchery. Blue, the barred rock, appeared to have a broken foot but seemed to get around decently. Last night I found her laying in the nest box but didn't worry. Today, however, she seems completely unable to move. About an hour ago she was given water. The other chickens had appeared to be pecking at her all day (really guilty that this happened) and she was flat out on her chest with her butt in the air. We picked her up and slimy clear liquid dribbled out of her mouth. We removed her and her crop feels like a water balloon and completely mushy. Going to separate her but don't know I she will make the night. Gave her food and she seems interested but barely ate anything at all. Please help. She just passed what appears to be clear foamy liquid with a yellow tint. Very lethargic.