Life and Times of John Snow – Pt 2: Sense of smell

Did you know that a dog’s sense of smell is our primary way of communicating.  It is how we interpret the world and is as important to us as sight is to you humans.  When we say hello to another dog, we greet by sniffing.  I can then tell what sex they are, what they ate for breakfast, who they have already met that day, what they have touched and what kind of mood they are in.  Clever aren’t we.

And it’s all to do with my wonderful nose, the longer our snout, the more olfactory glands we have.  These olfactory glands make us so much better smellers than you humans, whereas some of us can have up to 300 million olfactory receptors, you humans only have 5 million, and the part of my brain that analyses all these wonderful smells is 40x larger than your area.  This way we can identify smells 10,000 times or more  than you can.  This ability makes us so much better at search and rescue, drug detection, and all those other wonderful things that we help with. 

I think my nose is pretty special but the Bloodhound is the King of the noses, leading with 300 million receptors, followed by the Bassett Hound and beagles.  The hounds also have the advantage of extra skin folds around their faces to help trap scent and very long ears to drag along the ground to collect the smells up, so their sad dog look has a very useful function.

Another difference is that we dogs have an extra small organ called the vomeronasal organ or Jacobson’s organ.  This picks up pheromones, chemicals produced by the body to affect behaviour.  This helps me find a girlfriend in season up to 2 miles away!  I can also tell when a dog has been in a room that was frightened or anxious as they leave behind a scent that tells me so.  My mum produced a pheromone along her mammary glands and when I was nursing I would sniff this up and it would make me feel safe and calm.  There is now a synthetic version of this pheromone in a collar form, spray or diffuser, called DAP, dog appeasement pheromone.  It is really useful if you are a dog who is a little worried about things, like moving house, or coming to puppy school.  It helps to relax you.

Did you also know that my nose has a distinct pattern of ridges and dimples and in combination with the outline of my nostrils, make up a nose print, believed to be as individual to me as your fingerprints are to you.

I can also wriggle my nostrils independently- you cant.

This aids me in locating the source of smells, that’s why I weave back and forth across an interesting trail.

So when we go out for our walks, please make sure you give me plenty of free time to explore all those wonderful scents, this way i can check out all my sms and text messages that others have left behind as well as really ‘see’ my world.