I am heartbroken! My 9 month old Rhode Island Red crossbreed started acting weak (not moving much, eyes closed) on Friday ( we had fed hens a random mix of shrimp, noodles, and papaya, not sure if that is pertinent info). We isolated her and just soaked her in Epsom salts because we thought she was egg bound. Saturday, she laid an egg, but further deteriorated...lays down all the time, doesn't eat or drink. Someone gave us Sulmet (which was slightly expired, not sure if that matters) but we have been syringe feeding her Sulmet and water. Sunday, no progress on the Sulmet, and I started to see a clear, sticky mucus in her beak. Now it is Monday, I am getting worried it wasn't cocci, since I have never seen outrightly bloody feces. I switched to an antibiotic (oxytetracycline) and have been trying to syringe feed some sweet potato and mushed up starter feed with water. She is breathing very lightly ( sometimes I have to double check she is still alive), comb is completely bent over, eyes are always closed, head flops over all the time, as if she just doesn't have energy to keep it up, mucus in her beak. I had a feed store guy check and there is no impacted crop, but she does have a wet dog smell to her. Her feces was brown and solid(ish) this morning, but she still has diarrrea which is white and yellow, and white and brown. What could this be?? Viral? Bacterial? Should I continue with Oxytetracycline? Switch back to Sulmet? Both? I am a totally new chicken owner, please help!! I should also mention, we have 3 chickens in our coop and none of others have these same symptoms.