We realize it even just walking with our dog, his nose facing the ground to follow a track or leaning up to catch perfumes in the air that we don’t even think can exist.
But how does this “concentrate of technology” really work? How is the olfactory signal processed? How does an odorant become recognizable?
Last year, it was opened at the Teramo Faculty of Veterinary Medicine on Dog Olfactory & Cognition Laboratory, an olfactory and cognitive laboratory of the dog
It is dedicated to the study of the olfactory system of our friends and the practical consequences that their incredible abilities have not only in work and research, we think of dogs operating in civil protection, but also in everyday life.
Today we will discover the sense of smell of the dog, an incredible universe that science is exploring. We will discover something that we still do not know about the friend who is by our side every day …
1. How the Teramo laboratory was born
In Teramo, Professor Andrea Mazzatenta created the first laboratory in Europe dedicated to the study of the sense of smell of the dog.
Passionate dog lover, Andrea Mazzatenta, professor of animal psychology and psychology, has always dealt with smell, first at the University of Pisa and, today in Abruzzo, at the University of Chieti-Pescara and that of Teramo.
“Working in Abruzzo, also following the seismic events, it became evident that the use of research dogs was fundamental for saving lives”, says the professor.
“It is now established that the dog is a model for humans because, although there are differences in physiology, it shares life with us. It is an important peculiarity. He lives with us, in our homes, often follows us at work, also eats what we eat and therefore has become a model for a series of studies. In particular for the sense of smell “.
Hence the idea of creating a laboratory dedicated exclusively to the study of canine smell: “At the time there was no such thing in the world. A few years ago Professor Alexandra Horowitz anticipated me, creating a laboratory dedicated to the sense of smell of the dog at Columbia University. We are the second in the world, the first in Europe, we were born to transfer biological, physiological and psychobiological knowledge on the dog’s sense of smell to practice too “.
Yes, because the project of the University of Teramo does not only have academic purposes. The goal is to collaborate with bodies and institutions, including the Civil Protection, the Carabinieri, the Fire Brigade and so on, to train and certify dogs and operators for specialties based on the dog’s olfactory abilities: research on the surface and on rubble , anti-drug, anti-tumor, anti-diabetes, search for corpses, forensic activities, etc.
Knowing how the dog’s nose works, knowing how to read the signals the dog sends allows you to get better results in the job, in full respect of its well-being.
2. The nose is … the GPS
Dr. Mazzatenta and his laboratory therefore collaborate with the police, the Guardia di Finanza, the Civil Protection and so on to inform dog handlers on how the physiology of the dog’s nose works.
“By learning some rules of the dog’s physiology, the handlers realize when they have to take a break and when they can continue, they learn to read some particular signals that the dog sends.
We made a series of theses, for example with the Fire Brigade on dogs working for research scattered on rubble, and with the Guardia di Finanza to understand how the drug dog operates in pseudo-real situations, in particular what are the signs anticipators that the dog sends before identifying the substance.
With the Carabinieri we have done a job dedicated to the well-being of the dog: because if dogs are well, they work better ».
A very interesting thesis was made by the thesis artist Sara Ussoli, commissioner of the Emilia Romagna Region who works with surface research dogs:
«We installed a GPS in the harness of a surface search dog. Other GPSs were given to a helper who is missing and to other helper who are “confused”, they wander in the research area, “dirtying” the track.
With GPS we can follow the path of the dog and the missing person, as well as record environmental parameters such as temperature and wind direction. We have thus noticed how precise the dog is in following exactly the odorous trail left by the person, that is the “volaboloma”.
We can tell if the dog is working well, if he needs to take a break, and to compare the various research techniques, to understand which is the most suitable both to solve the problem, that is to find the missing person, and to ensure the well-being of the dog. Some techniques, in fact, provide for important physical stress.
For example, in the technique called “scovo with sending”, the handler tells the dog where to go: this technique makes the dog very tired, because he works much longer and covers a much wider path. Instead, with the “olfactory selection” technique, the dog goes hunting for the missing person using only the sense of smell.
He gets tired less, makes less road, even makes less road than the missing person, because if he can he cuts the track. It is a non-stressful technique for the dog, it makes it useful for several tests during the day and success is almost guaranteed ».
3. A super sense of smell!
Why does the dog boast a super sense of smell? What are the differences between our olfactory system and yours?
Professor Mazzatenta still answers us: «The most important differences are two.
– The first is anatomical: in the nose of the dog and man there is the sensory epithelium, made up of olfactory neurons. These neurons end on the surface of the epithelium exposed to the air with eyelashes. The number of eyelashes in man’s olfactory neurons is around ten, in dogs around one hundred.
The receptors that bind the odorants are expressed in the eyelash membrane: the dog, therefore, has a factor ten times more numerous than the human one. Imagine the power of his nose!
If the dog smells a molecule out of “N” millions, we have to move the bar very high: for us those smells do not exist, we do not have the “instrumentation” to feel them.
– The second difference it relates to receptors: in the dog we find about 900 molecules in the receptors, while in man there are about 400. Here too the dog has a power to “read” the world more than double compared to us.
The dog’s nose, therefore, is not only more sensitive because it has more lashes, but in the lashes there are receptors that we don’t have. The dog manages to read and combine odors in an absolutely peculiar way, we cannot even imagine what an olfactory signal can generate in his brain.
He manages to read nuances that are absolutely unattainable for us. That’s why in a crowded supermarket the dog can follow the owner’s track even though there are hundreds of other human tracks ».
4. A perfect “machine”
How does the olfactory system work? “In nature, we smell perfumes, not smells. Let’s take coffee for example»Mazzatenta explains.
«Coffee is one of the most complex perceptions because there are thousands of odorants released in the steam of hot coffee.
These thousands of odorants, once they enter the nose, go to stimulate the receptors and each of these odorants is read as an odor. Therefore, we pass from the chemical molecule, the odorant, to its psychological perception, the smell.
All these smells put together give the smell of coffee. In nature, anything we smell is always a mixture of odorants at various concentrations.
We always smell pleasant or unpleasant scents, and this requires significant effort on the part of the nervous system.
When these compounds reach the nose, the system breaks down the signal into individual elements, then the brain, starting from the olfactory bulb, recombines them by associating them with the area of memory and emotions to “give” a name to that perfume, for example the perfume of coffee.
All this is also linked to emotions: does sniffing coffee generate a positive, negative or neutral emotion? “.
Of all the senses, the sense of smell is the oldest, prior to the appearance of the thalamus, a structure involved in all other sensory systems. In contrast, the olfactory system sends signals to different parts of the brain but not to the thalamus. That is why scientists have not yet managed to understand exactly how the olfactory signal is constructed.
We know which routes are involved, but their integration is not easy. In the dog, then, there are seven chemosensory systems, so things get more complex.
In addition to the sense of smell and taste, there is Jacobson’s organ, responsible for the perception of pheromones. Pheromones involve an ancient area of the brain, the limbic system, stimulating the hypothalamus, the structure that determines the secretion of hormones.
This is why sexuality is linked to pheromones: the hypothalamus, in fact, will produce the hormones necessary for the various tasks, from courtship to reproduction. So for territoriality, aggression … All associated with the amygdala which is linked to emotions.
Then we have the Masera system, a small organ that is located in the nose, the terminal nerve (or zero nerve), the trigeminal nerve and the nasal ganglia system that is located on the tip of the nose and has the function of making us sniff, that is, to inhale noisily.
When dogs make this gesture, they activate the nasal ganglia which serve to bring as many chemical molecules as possible to the olfactory system for evaluation. ” In short, a complex and truly fascinating universe.
5. The uses of canine smell are many and growing
The Teramo laboratory does not only study the potential of the dog’s sense of smell but wants to give concrete help to all the people who work with dogs in an attempt to create shared practices that guarantee effective results and, not least, ensure the full well-being of the dog. working dog.
The applications of the dog’s nose are endless, from anti-drug and anti-currency dogs to those that do research on rubble and on the surface, from those able to identify accelerators for fires or electronic devices to dogs used by the Forestry Carabinieri.
There are dogs trained to sniff out tumors and cadaver dogs that can report submerged corpses.
“We are training dogs for diabetes alert that can signal the arrival of a hypoglycaemic crisis: it is a delicate and complex area.
And then there are the applications in forensic odorology, a criminalistic technique that allows you to collect the olfactory impressions left on the crime scene.
Just as fingerprints are collected, which can be important clues in a crime, so can olfactory traces be collected: perhaps a criminal has covered himself up so as not to leave fingerprints but still disperses the volaboloma, that is, the set of odorous molecules that each human being leaves behind and that the dog is perfectly capable of identifying ».
Knowing how our friends’ nose works, therefore, not only can help save lives but ensures that the well-being of dogs is ensured at all times.
Let’s not forget that these wonderful creatures are not machines, tools to be exploited, but friends who put their skills at our disposal and give us their help without asking for anything in return, happy to do so.