I would not lower the poly count any further that it already is. You may comprimise the integrity of the geometry. You have 2 areas that Ican see that need the tris taken out and quads added...


The Shoulder on the front legs you have 2 egdes coming off one and splitting ad quad into a tri. My suggestion would be to remove thos 2 edges and continue the edge already there to the top of the body.

The Shoulder on the rear hind quarters has a lot more triangulation that really is not need there. Do the same as above remove them and try to get the geometry into as many quads as possible. All in all it looks quite clean so far.

My only crit of the shape is the hind quarters... The rear leg does not rise far enough up and ends rather abruptly. As suggested before, grab Kurts free Cartoon Dog tute and see how he creates the hind legs.