muff

 John Wootton, Muff: a Black and White Dog. Photographic Rights © Tate, CC-BY-NC-ND 3.0 (Unported), museum record here

Might this appealing mutt named Muff have been a noble pet?  According to the painting's information page at the Tate, an old inscription on its reverse reads "From the Collection of the Duchess of Portland," and its date of creation c. 1740-50 would line up with the lifetime of Margaret Cavendish-Bentinck.  A gifted natural historian, she had particular interests in birds, seashells and botany; you'll notice the unusual bird and flower on the right.  John Wootton (English, c. 1682 - 1764) was a fashionable painter of sporting scenes, and enjoyed a good deal of patronage from the nobility.  He normally focused on horses, but let's face it, when the Duchess of Portland asks for a dog portrait, you make her one.  I'd like to think that the friendly, relaxed feel of this work had its source in the atmosphere around that gifted lady.