Humans and many other mammals breathe through their noses. But we humans breathe through our mouths as well. Surely you have used your mouth to breathe when you have a cold and your nose is clogged. The same thing is true with dogs. Dogs and humans have many genetic similarities. Dogs too use their nose to breathe but they make use of their mouth to draw in fresh air and to expel carbon dioxide as well. Notice how a dog would pant after a strenuous exercise. The dog would loll out the tongue and open mouth breathe. If you place your hand in front of the mouth you can actually feel the warm air being expelled by the dog.

Most people believe that dogs breathe only through their nose. It is believed that when the dog opens its mouth to pant, it is merely cooling itself. Party this is true. Unlike humans, dogs have no sweat glands. When the dog is tired out by running or working, the only way it can speedily normalize the elevated heart rate and disperse body heat is by panting. However, panting is another way of breathing. This open mouth breathing takes in and expels air as well.

Normally, dogs breathe through the nose. The scenting ability of canines is far superior to what we humans have. This is due to the fact that a dog’s olfactory bulbs are much bigger than human’s. Although both the nose and the mouth are used in breathing, dogs commonly use the nose especially when they are sleeping. Dogs in the wild would be on constant guard for their enemies. This is why you would seldom see a dog breathe through the mouth when it is sleeping. Breathing through the nose serves a dual purpose – breathing and scenting the presence of predators. Dogs have the ability to widen their nostrils when they are tracking or trying to identify a scent. A dog’s nose has a very distinct form. The slits on the side of the nose is where the warm air from the lungs is exhaled. Fresh air is inhaled through the nostrils. With this kind of arrangement, the fresh air being inhaled will not be polluted by the exhaled air, thus allowing the dog to scent better.

You now know that your dog can breathe both through the mouth and through the nose.  But breathing mainly through the mouth can be a sign of a nasal disorder. The dog’s nose may be blocked with foreign objects or the dog may have nasal tumor. If breathing through the nose is accompanied by a wheezing sound, a visit to a vet is a must.