have 8 beautiful birds from Mt. Healthy hatchery. One month ago added 2 Barvevelders and 4 copper Marans from a farmer. These birds looked a little "dirty" but I was assured they were healthy and in lay. Well, 5 days ago my barred rock started getting mucus coming from her nose and her beak was tacky. She looked like she was gulping air and her eyes were swollen and partially closed. She hasn't ate a bite and has drsank very little. She's been given drops of ChickenRX and also antibiotics in her water. She's been isolated from the flock for 4 days but now the Sussex is starting to look the same and the Barred rock looks no better. We looked up diseases and such and thought it was an infectious bronchitis but aren't really sure. Any ideas or advice would be great.