Both of my dogs are mutts. My definition of mutt is simply a dog that is not considered "purebred". I really take offense to the definition that says a mutt is "an inferior dog". My dogs may be goof-balls. They may not be the most well-behaved that you will ever encounter. They sometimes chew things they aren't supposed to, they bark too much, and they have poor table manners. But they are also affectionate, loyal, smart, laid-back, and happy.
Gypsy is a Shepherd and Elkhound mix. She weighs just over 50 lbs., but her ideal weight is probably closer to 40 lbs. When she was a puppy people always thought she was a full-bred...something. You look at her and you first see the shepherd, then you realize her tail is curled up, and upon closer inspection you realize you can't tell what she is exactly. When she was around 3 (and much closer to her ideal weight) people always thought that she was a young puppy because of the look she has, like she still had some growing to do. She's nearly 12 now and if it weren't for her girth she could still pass for a spry 3 year old. (In human years that's like saying she's 84 but could pass for 21. She would definitely get carded.)
Luna's picture should be next to "mutt" in the dictionary. When we got her last May she was only 3 months old and she looked like a black lab puppy, with just a little white on her chest. She's now 14 months old, and if you didn't know any better you'd still think she was a black lab puppy. She weighs about 33 lbs., she's still mostly all black, but her chest, belly and toes all have some white. Not a lot of white, just a coating. And that's what it looks like, too--like someone just brushed some white paint lightly over her just underneath. Underneath everywhere, including her tail and her chin. Her face actually looks like she stuck her snout into a bowl of milk, sort of a milk goatee. So based on the coloring and the size, there is no telling what she's mixed with. Lab for sure. Maybe beagle, maybe some dachshund too.
I have a friend who sent her dog's DNA to a lab to find out what breeds he comes from. It's been a few months and she is still waiting for the results. I thought about doing it for Luna. She used the Canine Heritage Breed Test, but there are several different products available. If her dog's results come back and are interesting I may do it.