I have a brand new hen I purchased on Sunday and when I brought her home and removed her from the box I feel like I heard two little coughs or sneezes. I didn’t think much of it because she had just been in a box and thought maybe it was a fluke. I wasn’t expecting it and it kind of caught me off guard so I wasn’t quite sure what I had heard. Last night I startled the hen when I went to close the coop and she made some kind of cough or sneeze that sounded very congested. I just went out and caught her to check on her and once I caught her she was breathing with this rattle sound that I was able to get on video. She is behaving normally and eating fine. No draining from the nose or eyes. What could this be? Do I need to treat my other birds since they have all been exposed to each other? If so what do I treat with and how?