Hello I have a 3 yo Rhode Island Red whom has been ill for over a week now. She has yellowish diarrhea, stands a bit hunchedback and is extremely lethargic. She had been very thirsty but not eating and today she is not even drinking and didn’t bother to leave the coop to roam the yard. Her comb is droopy and I think that her crop is enlarged compared to the other hens. Her stomach seems the same as the other hens. I have 3 other hens sharing the coop with her (different breeds) and they are fine. There have been no new chickens, all were babies at the same time and are all 3 years old. I bought some Corid that arrived today to try but she is not drinking now. I will post some photos of her dirty behind, her posture, comb etc. Any advice would be appreciated.