It is much easier to shoot a Zombie Dog out of the air than a Licker. In Leon's campaign, you encounter dogs in the Parking Garage after turning on the power. In Claire's campaign, you encounter them on the way to the Orphanage after exiting the Parking Garage. When you see a zombie dog, keep your weapon aimed in its direction (preferably shotgun or submachine gun) and wait for it to jump at you. The chance is high you will get it without trying.