What kind of sled dog was white fang? Why?

From the text:

"These are essential traits of the wolf and the wild-dog when they have become domesticated, and these traits White Fang possessed in unusual measure."

"He was a monstrous tyrant. His mastery was rigid as steel. He oppressed the weak with a vengeance. Not for nothing had he been exposed to the pitiless struggles for life in the day of his cubhood, when his mother and he, alone and unaided, held their own and survived in the ferocious environment of the Wild. And not for nothing had he learned to walk softly when superior strength went by. He oppressed the weak, but he respected the strong. And in the course of the long journey with Grey Beaver he walked softly indeed amongst the full-grown dogs in the camps of the strange man-animals they encountered."