I need everyone's advice. This Saturday I aquired 3 Sussex chickens. By morning the rooster was sneezing. They have been quarantined from the get go. Fast forward to today. 3 days on Duramyacin. They now have snot pouring out of their noses. They seem to be eating and drinking fine. I think we should cull them, but I don't want to do the wrong thing.The K-State Univerisity poultry specialist told me that unless I have been wearing a biohazard suit when handling these chickens, my flock has already been exposed to the virus ect. Does this mean that if I breed my chickens and sell them, I will be passing on this disease to other peoples flocks? If my flock doesn't show symptoms does that mean they weren't contaminated? Can I test them even if they are not showing symptoms.? This is so stressful. I have bought chickens before from this person with no problems. Thanks!