I went in our coop last night to collect eggs and check the hens. When I put down food for them, I heard one of the hens wheezing very loudly. I whistled to quiet the hens and she continued to wheeze and cough. I put her in quarantine and prepared an antibiotic for her water. She was eating and didn't seem bothered by her horrible wheezing. There was no nasal discharge, eye swelling, lightening of the comb or facial swelling. I went into the coop this morning expecting her to be dead, but she was just fine. No wheezing or coughing, nothing at all out of the ordinary. Does anyone have any ideas as to what might have happened?