That is responsible of you to have Misty's eyes CERF'd before breeding and I agree with Giselle about having OFA done as well. A temperament test would be a good idea too. I don't know Misty so I'm not saying she has a temperament problem, but it wouldn't hurt to have that test done so that you can guarantee temperament of the pups. The above should all apply for the stud you choose for her as well. You mentioned sheep, so I'm assuming Misty is a working dog and not a show dog? What is your goal in breeding?