I definitely know its respiratory issue in my chickens. I can't tell if it is spreading or not. Because there is no discharge from eyes or nostrels. What is really throwing me off is that one day a chicken sounds like that predator in the movie the next she is fine. Now I got another Hen weezing and she never weezed the day before. So it comes and goes. Evident and no so much. The actions I want to take is add antibiotics to their water. I looked at Tylon and it is too expensive so I got something else. Its called Tetroxy HCA-280. In the back it has section for chickens. I believe my birds have some form of Myc going on contagious or not. here is my question if I do have healthy birds mixed with sick and i put antibiotics into the water will it be bad healthy birds? If any1 has experience with tetroxy reply.