We got a hen in the fall that was gurgling, no other symptoms, but I did treat with Tylan 50 and nothing changed. What worked was a cool humidifier with oxine added to the water. I put a plastic tablecloth over the cage and humidifer together and let it run for awhile. Cleared her right up. Having said that she was fine until recently when the rains came again and I need to do it again. Still no other symptoms. What I read was in damp weather they can get fungus in their throats/lungs. My feeling was I had nothing to lose she wasn't coming out of quarantine until she cleared up or she would have to be culled. If you have oxine around give it a try.
