Yesterday everyone was fine, today one is making an odd mooing sound when she breathes. Obviously respiratory. GREAT!. She falls over when I catch her and she is gurgling. No one else is showing symptoms yet. She is separate. I have tetracyline water made up for the entire coop and I have convinced her to sip at some medicated water. I don't know what to do next. I have had amazingly healthy birds for 6 years now and now this. I will say I had a similar thing happen a couple years ago to just one bird right after turkeys had gotten into my chicken area. Well we just had wold turkeys in the pen right next to the chickens a few days ago. What I have on hand is : electrolytes, probiotics, tetracyline, Vetrimycin 200, and LA-200. Its whats in my medical boxes currently. Should I be looking for something else to inject? My husband can do the shots but no clue how to treat. I know I will have to treat the whole flock. No other symptoms like sneezing, just gurgling and the odd mooing sound.