"You see things as they are and ask, 'Why?' I dream things as they never were and ask, 'Why not?'"
-[The Serpent saying to Eve] in George Bernard Shaw's Back to Methuselah
What a great pose! Animals sometimes give the best poses/looks you could ask for! I like how the dog looks in the image, how you've filled the frame with him. But I would recommend changing the composition so that he is more to the left as I think it may increase the impact a little more.
"To photograph is to hold one's breath, when all faculties converge to capture fleeting reality. It's at that precise moment that mastering an image becomes a great physical and intellectual joy."
~ Henri Cartier-Bresson