I was gone for one week at my dads. My friend was in charge of animal care and did a great job! I came home and it was time to clean the coop and run out. I noticed one hen looked sick, her comb was dusky. I grabbed her, she was very thin, and had a large hard foul smelling poop clump on her vent. It had maggots total fly strike. I washed her vent really good, soaked her in warm water. Dried her off, set up a station for her with food water. I gave her held a banana and some tuna. I can tell she was just eating out of a response. Most animals will keep eating despite everything due to showing predators they aren't sick. It wasn't out of hunger or want. Her comb is dusky she does not look good. I have done all I can I think, any advice welcome. All my other hens were fine, poop is solid no coccidosis or worms in the mix. Plus there run is cut off from putter birds.