About 5 days ago I noticed one of my hens didnt leave the coop all day, she stayed under the heating lamp. The next day the same and so I figured she must not be feeling well, had no symptoms except seeming tired and cold. I moved her in to my house in a crate, gave her some vitamin water and fed her. She seemed not to be interested in eating, so I cooked her up an egg with garlic ( natural way to fight sickness) hoping it would help. She did eventually eat it, and Ive been feeding her eggs everyday sense with her grain. I noticed she was wobbling her head around a lot and sounded funny so for 2 days now Ive been giving her apple cider vinegar in her water. It seems to have helped a little, she seems to be gaging up some white icky stuff ever so often. She doesnt seem to cough really, her eyes are fine, she doesnt have a runny nose or anything. But her chest is all white with whatever she keeps gaging up, Im guessing the applecider vinegar has been helping to break up whatever is making her not feel well. Im debating going to get some tylan 50 to give her, Ive never had to treat any of my birds before so Im not sure if I should or not. The rest of my flock seems fine, i dont seem to have any other birds not feeling well. I would like to go through and disinfect the coop though to be on the safe side, whats the best way to do so when its sooo icy cold out? Any help or suggestions are greatly appreciated, thank you!!