Compact set chemistry

Fur Discolouration on a Springer Spaniel? - fur discolouration dog

Last year, when he went to my brother, his English Springer Spaniel has a clearly defined white fur with brown spots to visit. This year is now about five years ago, I noticed that under my nose, now all the skins are a kind of pink, and I wonder whether this is common in this type of dog. My brother had seen, but I do not think anything about it. No problem, and not by skin color or something to transfer, I'm just not sure why it would be changed.