nose and the fur is fading and becoming pink/red. is this a problem as am slightly concerned, it seems to be getting worse. also her gums are very pink ........

A dog's saliva contains enzymes that, due to a natural chemical reaction, can cause fur staining. (It's the same enzyme that causes tear stains in white dogs.)

You may want to bring her to the vet. If she's frequently licking her nose, she may need to be treated for an allergy or yeast infection.

In the meantime, make sure you keep the area clean, and make sure she always has a clean bowl of water. (If she tends to be a messy drinker, the saliva and debris in her water could be irritating her skin and reacting with her fur.)

I like the look of a american mastiff. They are so cute.