Hi, i picked up some new chickens on saturday and by sunday one displayed symptoms of coryza. I took her to the vet on tue and he prescribed antibiotics. Unfortunately although i isolated her other hens are now showing symptoms. My question is can i just let this disease run its course, see which hens get over it on their own with tlc. I realize they will be carriers for life and I'll have to keep a closed flock. Or do i need to treat all with antibiotics. Any info would be appreciated. What have others done when their flick was infected. Thanks in advance.