I recently bought twelve Cornish cross chicks. The second day I had them I noticed they were sneezing and at least one had a rattle to its breathing. They were at first on a medicated starter feed so I had hoped that would clear it up. I have since switched to a non medicated starter. I tried to put them outside but it got a bit too cold and I noticed the sneezing increase. They are inside again and many of them are still sneezing and some have rattle breathing. They are all eating drinking pooping and growing however. I'm not sure what to do especially because I don't want any medication in the meat. They are about three weeks old now. Any help?