Looks like the dogs front end (chest), wondering if it has been clipped. Colour reminds me of a Nova Scotia Duck Tolling Retriever, but they have a longer coat, and don't always have white on them. It is quite muscular, but hasn't got the rounded chest (if it is a chest) of a bull terrier, and even thought the coat isn't long, it's not short either... Some Golden Retrievers are this colour too. But though it is muscular, it's shape looks like a finer boned breed?
I'll go with the Nova Scotian Duck Toller for my guess