One year old Golden Comet hen. This morning when I went to do my chores she is making an audible breathing noise, weezing maybe? This came up just this a.m. No signs of sickness or listlessness, comb and wattles red. I cleaned their coop last Tuesday (wasn't even that dirty). I haven't noticed any discharge from eyes or nose. I seperated her in a crate and she went right to eating some layer pellets (which I removed because I don't know if this is a disease or a blocked airway). However I am really freaking out as I don't want to cull my entire flock if this is serious (so I'm in a total state of panic right now). So far I have only noticed one hen like this. Please help!