It's called "snow nose" and it's caused from lack of exposure to the sun. The reason I know, after we were in Colorado, Toto's little nose got a light brown spot in the middle. In a blind panic we took her to Alameda East in Denver ... to find out about that and to have her checked for any "defects". The doctor laughed and told us what it was and not to worry, all her dogs get that. The only thing, we have to watch for the other places that are black, i.e., her eyelids, lips, etc. She said that if the light spots appear in other places such as these, that it can be a sign of serious conditions. I just touch up the little spot if it shows in pictures!!
BTW ... she was pronounced "perfect" .... they didn't consider a little snow nose a defect!
browniesmom622 and I must have posted at the same time!!! Toto's
has to be lack of sunshine because Miss Prissy Paws will only eat from glass bowls! What a princess!!! LOL