I have 20 Cornish X chicks in a brooder right now. They keep sneezing. There does not seem to be any other odd conditions, very active, eating a ton etc.... The bedding that I am using is from a local mill and seemed to be a little more fragrant than the typical bedding that I have been accustomed to. I changed it out today, went back to the more expensive, less pine smelling shavings. Is this the culprit? Do I need to medicate? Any help would be appriciated.