What Causes Shallow Breathing In Dogs?

Heat. When dogs are hot, they pant or shallow breathe to keep cool. Put him in a cool place and give him cool water. A shaded cool spot would be good. Make sure he stays well hydrated. If he gets lethargic, too sleepy or irritable, take him to your vet.

Is the dog asleep or awake? It could just be its natural state of breathing. Other times a dogs breathing will become shallow when they are in a deep sleep.