petite lab coats

petite lab coats

What other breed could my Lab be mixed with?

I have an approx. 9 week old chocolate lab puppy that looks just like a full blood lab except for her tail. Unless her tail is down (which is hardly ever) she has a curled up tail. Not a tight curl, just enough that it touches her lower back. She also has a bark that doesnt sound like a lab..which could just be beacuse she is still very young. But it is almost like a high pitched growl instead of a bark. Her coat is short, but a little more coarse than most labs have and she is very petite for 9 weeks, only weighing about 10 pounds. Anyone have any ideas on what if anything she could be mixed with?