What Breed is My Dog?

She's a 3 year old that weighs 48 lbs with sort of a black and tan coloring. Occasionally she looks sort of a charcoal color instead of black. Her fur feels like velvet, she has a curled up tail most of the time. As she's gotten older, she has a pretty thick and muscular stature. At the dog park she tends to herd other dogs by chasing them and nipping at their rear ends some times.

By J.