katja, Pixabay
Discovering Your Dog's Nasal Turbinates
Everybody knows that dogs are blessed with a superior sense of smell, but have you ever wondered what makes your dog's nose so incredibly powerful?
Sure, with roughly 300 million olfactory receptors (while common mortal humans have just 5 to 6 million), dog noses are surely backed by some serious biological machinery!
But not many dog lovers know that at heart of a dog's olfactory powerhouse lies an intricate structure known as nasal turbinates.
Let's discover more about this secret weapon that helps turn every dog's sniff into a sensory symphony.
What Makes Dog Noses So Powerful?
Since dogs have become man's best friend, humans have relied on their extraordinary sense of smell. From tracking game to finding missing persons, and even sniffing out diseases, dogs have surprised us with their powerful sniffers, but what’s the secret behind this super-sniffing ability?
With about 300 million olfactory receptors, it's no secret that dogs are masters in the sniffing department. This acute sensory perception makes dog noses super sensitive which is why dogs are so intrigued by all sorts of smells.
To further make our noses turn pale in comparison, consider that dogs are capable of detecting a scent at concentrations of 1000–1,000,000 times lower than humans. In fact, they’ve been said to be able to pick up on scents as faint as one part per trillion.
Yes, you read that right—one part per trillion (ppt)! That’s like detecting a single drop of liquid in 20 Olympic-sized swimming pools.
If we had to make a plausible comparison that's similar to having a human search a needle in a haystack by using a magnifying glass; while our dogs are equipped with a high-tech metal detector. Yes, this should give you the idea of how powerful a dog's nose is!
If we had to list the dog's primary elements of their olfactory system, then the dog's nasal cavity, the vomeronasal organ and the nasal turbinates would ultimately take the show. Today, the highlights will be on those intriguing nasal turbinates.
No wonder we struggle to understand how dogs see the world—their noses are on a whole different level!
What Are Nasal Turbinates?
Nasal turbinates consist of an intricate maze of bones tucked inside the dog's snout. These scroll-like bones, which are covered in mucous, help maximize the surface area inside the nose which helps amplify a dog's reception of smell.
Think of them as some sort of roller coaster ride, where instead of thrilling riders, they take incoming air on a wild ride through the dog’s nasal cavity.
Each time the dog inhales, these turbinates take charge, and direct the airflow through a complex maze, which allows each individual scent particle to get caught and analyzed.
All the extra twists and turns allow more time for the olfactory receptors to do their job, turning every dog's sniff into a chemical analysis that would leave any laboratory scientist in awe.
The anterior parts of the turbinates (the maxilloturbinates, positioned on the maxilla bone-the upper jaw) are lined up with mucous, while the posterior parts (the ethmoidal turbinates) are covered with olfactory epithelium which house the olfactory cells and their receptors. These help transmit the odor information to the olfactory bulb of the dog's forebrain.
The intricate labyrinth of a dog's nasal turbinates
katja, Pixabay
The Power of a Longer Nose
When it comes to dog noses, longer is definitely better—think of it as the Pinocchio effect!
Here's the thing: the longer a dog's nose, the more room there is to accommodate those intricate nasal turbinates.
Move over English Bulldog! German Shepherds and Bloodhounds are the scent champions of the dog world, with long snouts purposely built for some serious sniffing. No wonder why they're often used as tracking, search and rescue, and sometimes even crime scene investigations!
So, while Pinocchio's nose grew with lies, a dog’s long snout is ultimately all about sniffing out the truth!
The shape of a dog’s snout determines just how turbo-charged the surface area of those nasal turbinates will be.
Can Dogs Breathe and Smell at the Same Time?
Yes, they can! Interestingly, dogs sport one air passage for breathing and another for smelling. As the dog inhales air through the nostrils, it can go through two distinct pathways: the upper flow path and the lower flow path.
The Upper Flow Path
When dogs are breathing, a small portion of air passes over the olfactory region in the nasal cavity, allowing them to detect odors. To be exact, about 12 to 13 percent of each breath will go straight up the upper flow path. The air flows through the nasal turbinates where odor molecules are deposited and prevented from being exhaled. The odor can therefore be carefully analyzed.
The Lower Flow Path
The remainder of the inhaled air, will reach the lower pathway, through the middle of the nose and below the olfactory areas. The air will then flow down the pharynx into the lungs.
This airflow system therefore allows dogs the uncanny ability to sniff continuously without interrupting their breathing.
Passive Smelling Versus Active Sniffing
Smelling refers for the most part to detecting an odor, as it may happen when a dog is breathing. This is in contrast with sniffing, which takes place when a dog purposely takes in larger quantities of odorants.
While dogs can passively smell scent while breathing, their ability to detect and analyze scents becomes significantly more powerful when they engage in active sniffing.
During active sniffing, dogs intentionally draw air toward the areas of the nose designed for olfactory processing. The inhaled air goes straight to the dog's olfactory cortex through the upper flow path.
Smelling and sniffing are therefore two different processes.
"Smelling is unconscious, effortless, and non-cognitive process of breathing, where air has only slight contact with the olfactory epithelium, whereas sniffing is a production of short, sharp breaths at 4 to 7 Hz in dogs." (Craven et al., 2009)
Dog nasal turbinates anatomy
Your Dog's Climate Control System
Dogs have some seriously impressive nasal turbinates. Along with giving dogs the opportunity to carefully analyze smells, those nasal turbinates act like your dog’s personal climate control system.
When your dog breathes in frosty air on chilly days, passage through nasal turbinates helps humidify and warm up that air nicely before it enters the lungs.
This happens courtesy of the anterior portions of the turbinates which are covered with a layer of mucous membranes.
And in the "dog days of summer" the opposite takes place. The turbinates help cool down the incoming hot air.
Thanks to a dog's clever countercurrent heat exchange system between small arteries and veins on their maxilloturbinates, dogs can handle prolonged chases, even in the harshest climates, considering that the turbinates help conserve heat and water during expiration.
These impressive nasal turbinate features may explain how, evolutionarily, canids were capable of surviving in a wide range of cold and arid climates.
While this nifty climate control system works great in keeping your dog's lungs nice and cozy no matter the weather, keep in mind, that dogs with shorter snouts (the so called-brachycephalic dogs) don’t share this same level of climate control, making them quite vulnerable on extreme weather days, explains Tim Lewis in the book "Biology of Dogs."
References:
- Alvites, R., Caine, A., Cherubini, G.B., Prada, J., Varejao, ˜ A.S.P., Maurício, A.C., 2023. The olfactory bulb in companion animals—anatomy, physiology, and clinical importance. Brain Sci
- Berg, P., Mappes, T., & Kujala, M. V. (2024). Olfaction in the canine cognitive and emotional processes : From behavioral and neural viewpoints to measurement possibilities. Neuroscience and behavioral reviews, 157, 1-12.
- Jezierski, T., Adamkiewicz, E., Walczak, M., Sobczynska, ´ M., Gorecka-Bruzda, ´ A., Ensminger, J., Papet, E., 2014. Efficacy of drug detection by fully trained police dogs varies by breed, training level, type of drug and search environment. Forensic Sci. Int.
- The Nosework Dog:Understanding Olfaction and Odors Manual
- Biology of Dogs by Tim Lewis, PhD
- Dogs: Their Fossil Relatives & Evolutionary History by by Richard H. Tedford and Xiaoming Wang
- Kokocińska-Kusiak, A.; Woszczyło, M.; Zybala, M.; Maciocha, J.; Barłowska, K.; Dzięcioł, M. Canine Olfaction: Physiology, Behavior, and Possibilities for Practical Applications. Animals 2021,
Disclaimer: this article is not meant to be used as a substitute for professional veterinary advice or behavioral advice. If your dog is acting sick or aggressive please consult with a qualified professional for proper diagnosis and treatment.
