Liver like spots on Boxer

Question
I have a three yr old female boxer.  she has been developing brown spots.  i first saw on inside of back leg, now on her side.  they are round, not raised.  no fleas.  she eats a good diet.  although i give her too many treats, but these are mostly dehydrated chicken or dingo bones.

Answer
I don't know what would cause liver-colored spots to form on a dog's skin unless she is chewing at the spot or licking it.
I would stop feeding her any bones whatsoever since these are deadly to dogs. I have seen one too many dog come in with perforated intestines from these things.
They don't usually survive either.
She could be developing freckles from aging also. Some breeds do that as they age.
If you are concerned about it then I would have a vet look them over.