I have a 1 year old Buff Orpington hen that is acting strangely, she is panting and clicking in a way that sounds like a goose, she has an abnormally large belly, I have tried to drain it but nothing comes out but digesting food, she is a chicken that is usually heavy, but is extremely light now, her poop is clear and yellow/greenish, I have searched it for worms but there is no sign of it, and I have treated our flock for worms recently, she is also not eating or drinking. She usually is the first one in the run to get treats, but she is not eating them or coming out to get them. I have already treated her for sour crop, but her crop is completely empty, I separated her from the rest of the flock, any suggestions?