What I would do:
#1: Separate her.
#2 Add electrolytes to the water + a little molassis.
#3Make sure she's warm and clean.
#4 Do a complete health check (eyes, nose, vent, check for color of comb, mouth(does her breath stink?), check her keel and crop for abnormalities).
#5 Also go to the link for symptoms.
Sorry for your troubles - hope it's nothing serious.