Even if you're not a dog person, this image has got to melt your heart. Beni just got a new haircut, and is posing proudly in front of the camera, giving me a chance to test the new lens out.
Animal photography is a very hard thing. First it takes a lot of images to get the one that you are satisfied with, and second you can never predict what they are going to do (which in some cases is actually nice, since you can get funny images that way). If it's your own pet, then you will not have as much problems, but if you're shooting wild animals or someones pet it can get tricky.
I aim the focus at the eyes when I'm doing a full body portrait with a dog (like this one). If you're going for an extreme close up, then you should probably focus on the nose, otherwise you'll end up with a big blurry dark object in the middle of your frame. This of course if you're using a small f-stop number (f1.8 in this case). Alternatively you can opt for a higher f-stop number like 2.2, 2.5 or 2.8 in order to get a wider field of sharpness but still maintain that blurry background which, let's be honest, is what makes the image pop up and make it look more like a pro's image.