I have a 1 1/2 year old Angus steer who has recently developed a patch of skin on his neck that is thick and kind of scaley, crusty like. It is about the size of my hand. He is with 2 other cows who are fine. The hair looks fine there, but you can feel the crusty stuff when you pet him. What is it, and what can I do to rid him of this problem? Thanks!!!