It has been a lasting common phenomenon over the years that if your dog has a cold and wet nose then it is a sign of good health whereas if it has a warm and dry nose then you should be worried and think that something is wrong or about to go wrong. It’s actually not that simple. Your dog could be wet and cold or dry and warm at different times. So it is not that black and white; because most often dogs have warm dry noses after a good sleep and then the rest of the time, they are just wet and cold.
The point here is that the temperature of the nose is a very weak sign to use in predicting or suspecting something to be wrong unless it is accompanied by other contributing symptoms such as withdrawal from daily routine activity, diminished appetite, changed sleeping habits and many more.
Until recently, no one understood what made their nose wet and cold. Turns out it is moist mucus that is secreted in the nose by a special mucous gland, which is according to scientists from Pennsylvania. Let us look the theories that have been put forward to try and explain the wetness in dogs’ noses.
1. Smell-identification: During an experiment, dogs had images of their noses taken using an Magnetic Resonance Imaging (MRI). The purpose of the experiment was to see the movement of different particles through the nasal cavity. To see the path these particles took as they entered the nose and reached their receptors. They found that the molecules that carry a variety of smells have to first pass through a moist layer. Here they are speedily and carefully sorted and filtered before moving to their smell receptors. The called this step the ‘pre-sorting step’. It is in the pre-sorting step that makes dogs so amazingly efficient at picking up smells. What happens is that the brain cortex efficiently picks on these pre-sorted smells and then provides a feedback signal to the smells at rapid speed. Therefore, dogs’ wet and cold noses are an ‘always’ sort of thing because they are constantly in an environment where they have to process various kinds of smells. This might translate into another common assumption that most people have come to agree upon that: the wetter and colder the nose of a dog, the better and more accurate it is as spotting certain smells.
2. Perspiration: Since dogs’ skin is covered with hair, it makes it almost impossible to sweat (perspire). Mammals maintain a homeostatic environment by balance heat. This is done through a process called perspiration where our body loses water through skin. Since dogs cannot do it through their skin pores, they use their noses instead. When they look like they are hyperventilating (panting), they are actually perspiring water from the bodies through their open mouth and nose. Sweat glands found in dogs’ nostrils allow them to produce very clear watery liquid which warms their noses and leaves the area around it wet. Perspiration is a physiological process and thus it continues throughout the day.
3. Part of being a dog: Every now and then, you catch a dog rubbing its nose with its stuck out tongue. So far, there are no particular standing theories that can explain why they keep doing that. Maybe they just like to keep their nose warm and so the lick it to make it wet. Some people believe that after having a meal, since the nose is normally used in the eating process; once they are done with eating, licking the nose and the area around it is sort of like washing up. More like the way we wipe our outer oral cavity after a meal. Dogs lick their nose to rub off whatever food particles remain after eating.
4. A gift from God: According to popular Christian legend, when Noah’s ark was about to sink from the small leaks, the dogs stuck their noses in each hole and prevented the ark from sinking therefore saving Noah.
5. Biology: Just like the way some of us are born with dry skin, blue eyes or wet palms, some dogs are just born with wet noses. Biology makes the call. That means there are some dogs that have dry and warm noses while others who have cold and wet noses. No further explanation behind that, except that its biology or you could as well call it genetics.
So far these five theories stand out in giving a probable and maybe reasonable explanation to why dogs have wet and cold noses. One thing for sure is that the temperature of a dog’s nose does not give reliable information into the health of a dog.