Thank you! I dropper fed her corid water through the night and she seems better this morning. I'm keeping an eye on her, but she is eating and drinking--as well as hanging out with the others now and having normal bowel movements. She is normally one of my flightiest birds, but yesterday she would let me pick her up and just lay there like a potato poor thing. Today though when she saw the spoon I use to clean out the brooder, she made her funny little salmon faverolles squack and ran away.
She doesn't seem to whimper when defecating. I'll look up salmonella infection symptoms and keep an eye out for those. I'm thinking that maybe my mistake was that three days ago I gave the chicks corid in the water, but I mistakenly used tap water to make the chick food mash. So maybe she wasn't getting enough corid and just getting hydration through the food with tap water. Maybe now that the mash has corid water she's responding better.
Thank you all so much! I so appreciate it.