Help! I have a 3 month old salmon favorelle who has always been a bit of a weak chicken. She was badly pecked as a young pullet, now generally left alone, but is small and mellow. The last 2 days she has been increasingly lethargic. She has been standing in the same spot all day in the run while the other pullets are out roaming. She lets me pick her up and check her out without much protest which is unusual for her. She seems to be eating a little bit but not much. I have seen her drink a little water today. Her poop is white and green but nothing that seems really abnormal. Her butt has dried poop on it and stinks but vent is clear. I saw some tiny little dark particles near rear but couldn't tell if they were poop particles or mites? I didn't see any of them moving. Her crop feels small ,hard and skinny and long--kind of ropey. It doesn't feel like the other chickens' crops.
The other chickens seem fine and are all significantly larger than she is.