I am confused on what I should do for my hens. They are sneezing, and have a little clear liquid coming from there noises. I noticed that four out of the five have this problem, the older hen does not show any signs. I spoke with a vet when I first seen the problems and was told to check to see if it's getting worse, and if the hens start to act like they feel bad. Well, it been a week they have not gotten worse, and seem to be in good health, other than the sneezing. What should I do next? If an antibiotic is needed, what should I get?