I mean, they can. Breeders often focus on a specific breed (or breeds) of dog, and puppy mills will usually claim to do the same, even though many will crossbre

I mean, they can. Breeders often focus on a specific breed (or breeds) of dog, and puppy mills will usually claim to do the same, even though many will crossbreed and not tell you. Shelter pups are likely to be more mutt-y than what you'd find at a mill or breeder, often with 5 or 6 different breeds of dog in it.