One evening my Barred Rock hen, who I've had for well over a year, bumped into the back of my legs when I was feeding the rabbits. I looked at her and she looked a little funny. I picked her up and noticed her face was swollen and her eyes were watery and bubbly I think she bumped into me because she was having a hard time seeing. No sneezing, coughing, discharge or any other sign of illness; her appetite was normal and she laid an egg that day. I immediately put her in quarantine and started searching everything I could find on swollen face and bubbly eyes. Nothing seemed to fit and it was too late in the day to talk to a vet. The next morning she was perfectly fine, the swelling was gone and her eyes were normal and she wanted out of quarantine. I thought she must've tried to eat a bee or something and I went to set her down with her coopmates and I heard a sneeze. I picked her right back up and put her back in quarantine and called my vet who referred me to the state vet, who happens to be located within 10 miles of me. The state vet came out for free that afternoon and swabbed throats and took blood on my Barred Rock and 5 other birds in the flock. The vet was very nice and seemed happy to help me, but I got the impression he thought I was one of THOSE people, the ones who call for professional help over every little thing. After all, this bird looked perfectly healthy right then and I only heard her sneeze once. He kept telling me he thought it was nothing, but we may as well be sure. I got the call yesterday afternoon that it was MG (Mycoplasma gallispectum) also known as CRD (Chronic Respiratory Disease). He told me that MG is common in backyard flocks and the state doesn't have a protocol for dealing with it. The source is a trio of bantams I bought last month. I had quarantined them and they showed no sign of illness, but MG survivors are carriers for life and they infected my birds while showing no signs of it themselves. He said it was especially telling that one of my birds that has never been off my property got sick when the newcomers did not. UPDATE: I did cull my original flock and accepted hatching eggs from some generous BYCers to start over again. Now, I never bring in started birds and I will never show my birds because poultry diseases are spread too easily. MG is common in wild birds, but I've never seen any signs of it in my current flock.