I have sick birds. They are all about 8months old. Mixed heavy breed flock. They are not all showing signs of sickness yet, but those that are have runny noses, I have heard a cough here and there, one has swollen waddles and is lethargic, all pretty standard respiratory infection stuff. I contacted a vet at the NC state poultry science departments, she says it is probably viral. The folks at the feed store said to treat with antibiotics...which won't do any good for a viral infection, but can treat any secondary bacterial infections. I am trying to get in touch with the state Ag Dept, to get my chicks tested, but it is the weekend, and then I have to wait for results. My questions are... 1. Would you go ahead and treat the whole flock with antibiotics or just the birds with positive symptoms? 2. Would you treat them all with Tylan 50 or just some antibiotics in the water? 3. Or would you just let the virus run its course and hope for the best? 4. How many days do you treat with Tylan 50? So confused about how to proceed.