Your Dog Is Nose -y

We see the world through our eyes.  Our dogs see the world through their noses.

It’s common knowledge that dog’s have a keen sense of smell, but did you know their brains process those smells that really makes the difference.

First off, a dog has more then 220 million smell receptors.  People have a measly 5o million.  In particular, a dachshund has 125 million, a fox terrier has 147 million and a bloodhound has 300 million.

Otherwise, however, their noses are very similar to ours.

Let’s talk a little about the anatomy of the nose.

A dog’s nose is divided into two parts.  The divider is a structure of bone and cartilage called a septum. The human nose is much the same.

Inside the nose, both dogs and humans have bony, scroll-shaped plates called turbinates. The front area of the nasal cavity is called the nares.  Air passes through these to be warmed and moistened. The turbinate bones are located farther back in the cavity. They are covered by olfactory mucosa, which is a thick, spongy membrane consisting of millions of thin, hair-like structures.  These trap scent molocules that are then processed by odor-detecting cells on the tips of the cilia, or hair-like structures.  All this is basically the same process we find in humans.

The difference starts with the Jacobson’s organ, scientifically known as the vomeronasal organ (VNO).  It is an especially sensitive part of a dog’s sense of smell and is an elongated structure that consists of two small cigar-shaped sacs filled with receptor cells.  These cells are sensitive to chemical messengers such as body scents.

Once these receptor cells pick up a scent molecule, a message is sent to the brain. The percentage of a dog’s brain devoted to analyzing smells is 40 times larger than the same area in a human. 

The brain processes the information sent to it, identifies it and determines its significance.  In other words, a dog uses its sense of smell to help it determine it’s view of the world.

One aspect of a dog’s nasal system that is different from ours is that he has two different air passages – one for inhaling/exhaling and another for smelling.  People use the same passage for both.  That means the scent molecules that are inhaled in our noses just get exhaled almost immediately. A dog, on the other hand, can store his while he exhales through a different passage.

Another unique characteristic is that a dog has the ability to smell independently with each nostril.  This is how he is able to determine from which direction a scent is coming.

The power of a dog’s sense of smell is unique and remarkable.  It can be trained to detect bombs, drugs and even disease.  It helps him detect sadness and know to be there when he is needed.

And, of course, the dog uses his sense of smell to determine friend and foe in both the animal and human species.  It helps him find a mate. Through his amazing sense of smell, he can learn a lot about his friends and neighbors – probably a lot more than we will ever learn about ours.

It truly is an amazing aspect of these wonderful animals

But the scent discriminating ability is not the only thing unique about your dog’s nose. Each nose has a pattern of ridges and dimples that, when combined with the outline of the nostril openings, make his nose print. These are believed by some to be as unique and individual as a person’s fingerprints.