What would happen if you bathed a mostly white dog with non-white markings with a whitening shampoo? Would something happen to the non-white markings? The thing is, Basil is about 80% white, with brown markings on his face/ears and lower back/tail area. Some of his white fur, like on his paws and tail, tends to get a little yellow, so I was considering trying a whitening shampoo on him. However, I don't want to mess up his gorgeous brown markings, so should I use two different shampoos, one for his white fur, and one for his brown fur? Or will he be okay with just whitening shampoo?