Dear Molly,
While we might not know all the reasons dogs have wet noses, I was able to sniff out a couple answers for you. I couldn’t have done it without some help from my friend Katrina Mealey, a veterinarian and researcher at Washington State University.
As a veterinarian, Mealey invented a medical test for dogs to make sure they get the medicine they need to stay healthy. She cares for all kinds of animals and knows a lot about dogs, including her own German shorthaired pointer, who also has a wet nose.
Dog noses come in all shapes, sizes, and colors, and pretty much all of them are wet. Most often a wet nose is a good sign that they are healthy, Mealey says. We do know that a wet nose helps dogs maintain a nice body temperature and helps them smell.
In fact, a wet nose can actually help increase a dog’s ability to smell. While you have wet boogers and mucus up inside your nose, dogs have something kind of like mucus on the outside of their noses. It’s called serous secretion and it comes in handy when they are sniffing around.
Maybe you can think of a few of your favorite and least favorite smells. All smells are really just a combination of chemicals, made up of building blocks called atoms. When the chemicals join up with each other in different arrangements, we smell different things.
The moisture created by the serous secretion that comes from the dogs’ noses can help them capture different chemicals in the air and smell better.
Dogs also have wet noses because they lick them. If you can make your tongue touch your nose, you are part of ten percent of the population that can do it. Go ahead and give it a try. Any luck?
It’s much easier for dogs to lick their noses. Dogs will use their tongues to spread the serous secretion around their nose and create even more moisture, helping them smell even better.
A dog probably smells all kinds of things we can’t even imagine, Mealey said. Dogs have more than 300 million little receptors in their nose that help them smell, while humans have only about six million. This great sense of smell makes some dogs really great trackers.
Mealey also said that dogs don’t sweat all over their body like humans do. Instead they have little glands on their paw pads and on their noses. These glands produce a little liquid that evaporate and cools their body.
Maybe you’ve experienced this when you got out of a pool on a sunny day and felt a bit chilly. The water was also evaporating from you and taking some of your body heat along with it.
“Evaporation on their nose helps cool them down a bit,” Mealey said. “We believe that’s one of the way they make up from not being able to sweat a lot.”
Along with panting, a wet snout can help a dog keep its body temperature just right.