Zeke has had an ongoing" crack" on his right nostril now for 2-3 years that looks VERY much like that. After finally doing a biopsy and histopathology we discovered it was mucocutaneous pyoderma, basically an immune disease that is genetic, german shepherds are predisposed to it. His is a staph infection. We treat it with basic antibiotics, oral at first, along with an antibiotic cream. It goes away, then a few months later comes back and we treat again. He will have this for the rest of his life, it will never go away. The cream alone now is usually enough to take care of it but SOMETIMES he still needs oral antibiotics.
I would keep an eye on it, but if it doesn't start to heal or go away within the next couple days go to the vet and at least try antibiotics to see if it helps with healing. Cephalexin and Clindamycin work well for him.
__________________
~Emergency Vet Tech
Berlin vom Spartanville 1/13/13
Zeke 5/25/07
Luther

2008 - 7/23/12
"Take this trouble from me: Make sure my shepherd dog remains a working dog, for I have struggled all my life long for that aim." Max Von Stephanitz