My Prim, a year old Buff Orpington, has developed a mass on the top of her head. I thought at first that it was just a fluid filled cyst (thought maybe the rooster bit her on the head and pulled her skin a bit), but it has been about 3 months and it has gotten bigger and more firm. It is at least half the size of her head now. I don't have any pics of it, but I can try to get some. Any ideas??