my chicken has been living in a barn for the past month and a half...before that he was living in my basement...now it seems he has a breathing problem. he is weazzing a lot. when u hold him, u can hear something in his throat. I've been reading the forms and see that tylan 50 is used to treat this. but where can i buy tylan 50? I live in Green Bay, WI. Can i buy this at feat farm, or any pet shop?