I have a pullet that sounds like she has a respiratory disease. She sounds real "wet" when she breaths, sneezes on occasion and just doesnt sound healthy. She was a meat chicken from a hatch project at the local elementary school that my niece brought home. She has never been invited into the main flock so is a loner, but other than the other chickens attacking her when she gets close, none have contracted whatever it is she might have. Should i put her down? Leave her be? I have no idea of the breed other than shes white and VERY fat. Shes about 5 months old.