I purchased some chickens from a guy on craigslist a week ago. One of them has respiratory sounds. Sneezing, I can hear her breathing and she's almost gurgling... And yesterday someone laid a wrinkled egg. I have separated her from everyone (I bought 7 hens - and the others all seem fine). I have had them for a week - should I cull the one who sounds so bad and keep the others isolated?? I don't want her to give this to everyone - Any advice?