Slate shanks are recessive, and the id gene (dermal melanin) is sexlinked, so a white-legged roo over a dark-legged hen should make all white shanks. Should. The genetics are a often little more complicated than that.
Assuming your D.White roo is entirely dominant white, he'll produce all white offspring. They'll have a few black feathers because they won't have inherited D.white from their mothers. The recessive white will not affect their colouring, as they'll only have one copy of it.
Assuming your D.White roo is entirely dominant white, he'll produce all white offspring. They'll have a few black feathers because they won't have inherited D.white from their mothers. The recessive white will not affect their colouring, as they'll only have one copy of it.