I've read many threads about this, but am unclear if I should be concerned. My 14 week old chicken is free of apparent respiratory issues, has a hearty appetite, normal energy levels and behaviors. The only symptoms are occasional mouth breathing (5-10 times and then stops for an hour) as well as diarrhea for a couple of weeks that seems to be improving. The mouth breathing is not getting worse. We did lose a bird 2 weeks ago - sudden death, possibly Coccy - don't know, and I've since treated the whole flock for Coccy. I didn't notice open mouth breathing in the one that died, but we were out of town for a few days prior. I have not wormed them and don't want to overtreat them unnecessarily. I looked down her throat and didn't notice any worms, but I wouldn't count on my reliability, being a first timer. Are the gape worms as thin as thread? White? What else could this be? It's not hot out. Is this deadly at this point? Or can I wait and watch some more? My kids would be devastated if we lost another so soon.