To estimate Wikipedia, 'When puppies would not have real eyebrows, they do have a particular ridge above their eyes, and several breeds, such as Labrador Retriever, Gordon Setter, Rottweiler, Bernese Mountain Dog, German Shepherd, and Doberman have markings there. http://daltonwigbv.worldblogged.com/16705212/dog-with-eyebrows-an-overview