When you look for a dog or are selecting one from a breeder, shelter or rescue agency, many veterinarians suggest that you check the dog’s nose. Healthy dogs should have cold, wet noses, clean rectums, and bright eyes without any film on them, and they should appear clean and relatively free of fleas. Of course, you may have already had to field the question as to why dogs have cold, wet noses. Any child is bound to ask, and there are actually multiple explanations and no consensus on exactly why.
First off, you may have noticed that dogs don't sweat. Their principle means for cooling down is by opening their mouths wide and panting. Some scientists suggest that having cold, wet noses also plays into this cool-down equation. A little moisture on the nose keeps it cooler (hence the cold), and therefore helps to keep the dog cooled down on hot days. A dry nose is not a good sign, and might suggest that the dog is dehydrated, and a warm nose suggests the dog may be running a fever. If this condition persists for more than a day or two, you should head to your vet to have it checked out.
Another reason that dogs have cold, wet noses is because they’re quite fond of licking their noses. Many dogs have long tongues with which they can easily reach their nose — possibly enhancing coolness and transferring moisture to the nose. Further, after a dog has eaten, you’ll frequently find them using their tongues to clean off their noses, particularly when the meal is messy. This in turn leads to the cold, wet noses we’ve come to expect in dogs.
An alternate explanation as to why dogs have cold, wet noses may have to do with survival skills, and predate domestication of our furry friends. It’s suggested by some scientists that extra moisture on the nose may increase a dog’s olfactory capacity: in other words, the dog’s sense of smell. While the modern pampered pooch may not need to have a particularly good sense of smell, this aspect of the dog is still relied upon. Working dogs especially, need great “smelling” skills to herd, find pests, look for missing people or sniff out illegal substances at airports. Cold, wet noses may simply be better at smelling thing than a dry nose would.
The dog that likes to explore outdoors will frequently present its owner with a very cold, very wet nose. Dogs can pick up moisture from the ground or grasses, and if the weather is cool, their noses are liable to be even cooler. While it may not be the best thing in the world to be sniffed over by a dog who’s just spent some time exploring the outdoors, and while the reasons may be something of mystery, cold, wet noses tend to serve dogs well and be just one of the features expected in these animals.