Because the photo itself reminded me a great deal of Tex Avery's 1940 Warner Bros cartoon "Of Foxes and Hounds", featuring a dim foxhound named Willoughby and a fox named George. And if you haven't studied English at school, you'll realise this is possibly the first stab at John Steinbeck's renowned novel Of Mice and Men in animation history, with the original George and Lonnie characters in mind - a concept that Tex would later adapt into his George and Junior series when making his name at MGM Studios.
Oh, and speaking of which, 9 years later at MGM Tex directed another, funnier fox hunt cartoon starring Droopy - Out-Foxed - and featuring one of Daws Butler's first-ever roles as a voice actor in animation.
Notice how this dog costume would later evolve into a bear...? ;-)
And here are the two cartoons below for you to enjoy =)