I went out this morning and one of my hens didn't leave the coop and was sitting with one eye closed. She stayed like this for a few hours. Then she came outside and the eye opened a little but not all the way. I was thinking she can poked in the eye. Later today she now seems to be having trouble breathing. I have isolated her. She laid down and sorta sleeping. No sneezing, no watery nose. But some gurling sounds. I'm getting very nervous. I have read a bunch of threads and it doesn't sound good. It seems now she will have this for her life and pass on to everyone else? They say to kill her and have her tested. Could this just be something else that she will heal with? Everyone else seems fine. Could it be anything else besides a respiratory infection. I did do clean out the coop yesterday but everyone was outside while I did and outside for hours after. Thanks for any input.