How far can a dog smell? The dog's nose as it is - interesting facts. Nose of a healthy dog

A feeling that has no equal.

Smell- the most important feeling of a dog. Throughout centuries of evolution, a wild dog had to follow the trail in the right direction, otherwise it would die of hunger. The dog uses it for hunting, for orientation in the area, when communicating with other animals and determining their taste preferences. A dog recognizes its owners and its home by smell rather than sight. The sense of smell is also important for assessing the quality of food and its choice - in this it even prevails over taste sensations. If the dog does not like the smell of food, she refuses it.

The olfactory sensitivity of dogs is almost a million times greater than that of humans. Dogs have 40 times more odor-recognizing cells in their brains. Strong sensitivity to odors is also due to the large area of the receptor organ: in a dog, the area of the mucous membrane of the olfactory region of the nose is approximately equal to the total area of its skin, while in humans it is only a few square centimeters (about the size of a postage stamp).

The number of olfactory cells in dogs is very high, although it varies depending on the breed (for example, in Labradors and German Shepherds - 220 million, in Cocker Spaniels - 70 million). Importantly, the region of the brain responsible for recognizing olfactory stimuli is almost 10 times larger in dogs than in humans.

Perception of smell.

The structure of the nasal cavities in dogs contributes to the good development of the sense of smell. The nasal conchas are lined with a mucous membrane, equipped with many olfactory receptors. Every healthy dog has a very moist nose, the moisture washing over the receptor cells. And since all odors are chemical in nature, they instantly dissolve in this liquid. The nasal conchas have a spirally curved shape and are separated by sinuses (sinuses), into which flows of inhaled air enter along with odors. Another organ of smell is the ethmoid bone in the depths of the nasal cavity, which also contains sensory cells. Five cranial nerves are also involved in the perception of smells in dogs.

Molecules of aromatic substances, coming into contact with these sensitive cells, bind to specific receptors, causing chemical reactions, as a result of which a signal is sent through the olfactory nerve to the corresponding area of the brain, where the information received is processed. Currently, more than 300 types of olfactory receptors have been discovered, each of which is associated with a specific "odotope" (part of a chemical molecule) - the odor determinant. A dog can distinguish up to 2 million smells. The degree of perception of the smell of an aromatic substance depends on its chemical composition, molecular weight and humidity of the inhaled air. Heavy molecules, sparingly soluble in water, are perceived more easily. These principles underlie the work of sniffing dogs used in the service and search service - from search and rescue operations to the detection of drugs, weapons and explosives.

Sensitivity to odors.

Dogs don't smell very quickly. The odor molecules must not only penetrate the nasal mucosa, but also bind to the right receptor. It often takes a while for the dog to recognize the smell. Equivalent stimuli are needed to cross the olfactory threshold and elicit a response. When all specific olfactory receptors are involved, the dog's sense of smell decreases (mostly after 30-45 minutes) due to the so-called olfactory fatigue. Once it sets in, the dog needs to rest to give the receptors time to release. The dog's sensitivity to smells is optimal after 2-4 minutes after the start of work, the rest phase lasts 3-4 minutes. Every dog has the ability to “read” smells to some extent.

The custom of all the surrounding dogs to urinate on the same pole is associated with survival and the ability to analyze the smell of urine, with the help of which, like wolves, they will find out which of the animals lives nearby.

And in conclusion - some useful information for guides of sniffer dogs.

Bitches have a sharper sense of smell than in males, but it depends on the estrous cycle (estrogen, like the male hormone testosterone, has a positive effect on it).
Pigmentation nasal mucosa affects the olfactory ability. Dogs with light mucosa work less efficiently.
At the sharpness of smell dogs can affect biological factors(hunger improves it, while poor general health or physical fatigue, on the contrary, reduces it).

Nose care: no special nasal care is required. But you need to remember that the nose at any time of the day should be wet and cool, normally it can be dry only during the dog's sleep. Chronic dryness of the nose in the presence of redness in the corners of the eyes can signal that the tear ducts are blocked. This means that your animal needs a visit to the doctor, as well as significant irritation or the presence of mucopurulent discharge from the nasal cavity.

The nose of a dog, its sense of smell is an amazing world of smells, about which a person has an approximate concept. Humans have approximately 5 million olfactory cells, while the average dog has over 125 million. The cerebral cortex responsible for the sense of smell is larger in dogs than in humans. In this article, we will discuss the dog's nose, how it is and its abilities.

Dog nose, its structure

The dog's nose is covered with mucus. This is exactly the mucus that a person has inside his nose. And in a tailed friend, this mucus covers most of the nose, not only from the inside, but also from the outside. The mucus produced by the glands of the lining of the nose is a kind of filter through which the molecules of the odorous substance are analyzed by the animal. We have already touched on this topic. Now let's talk about smell in more detail.

The very structure of the nose is amazing. The nostrils of furry pets have been subjected to scrutiny by scientists. And here's what scientists found out about the nostrils. The side openings of the nostrils play an important role in the recognition of odors. If the dog simply inhales air, then about 47 percent of the air enters through the side cutouts of the nostrils, while sniffing - already 53 percent.

Also, the dog receives information not only during inhalation, but also during exhalation. If she breathes through her mouth, then part of the incoming air does not pass into the lungs and, when exhaled, exits through the nostrils, where the air is processed by the receptors of the nose and analyzed.

However, during oral breathing, air enters only through the round nostrils, without affecting the side cutouts. And this suggests that the quality of the sense of smell is reduced, since new smells cannot be detected.

If the dog is calm, then the nostrils can collect information from the air in front and side. Right in front of the dog's nose there is an air space from where the air is not drawn in by the nostrils. It is 60 degrees, 30 degrees for each nostril. In a calm state, the sector of coverage of the air mass is from 30 to 130 degrees from each nostril.

But if the dog's nose is alert, then the side cutouts are folded in such a way that they can absorb air from behind. In this case, the dog does not even need to turn his head, since the coverage sector is already from 30 to 150 degrees from each nostril.

It turns out that the side cuts of the nose are an important tool with which the dog is well oriented in space. Studies have been done in which dogs have these side cuts sutured. And then they immediately lost the ability to orient themselves in space with the help of smell.

Why does a tired dog's nose work worse?

It is common knowledge that a tired dog begins to smell poorly and needs to rest. This is due to the fact that during physical activity the animal is increasingly switching to oral breathing. This means that only 5-15 percent of air enters through the nose. This is not enough for a deep analysis of odor recognition. Therefore, the pet needs to rest. When the dog sniffs carefully, his breathing should be deep and slow.

The dog's nose is unique. It can differentiate odors. A person is practically incapable of such a thing. Only high-class professionals can break the overall smell into components. Whereas any dog is able to analyze odors, looking for even a very small amount of an odorous element against the background of other, rather strong odors. It is this quality that people use when they hire a furry friend.

What can a dog's nose detect?

Dogs help people not only in search of drugs or a person. Our tailed friends are doing well in other areas as well. For example, in Sweden, about 70 percent of buildings are infected with mold. Of course, the damaged parts of the structure must be replaced, and 200 dogs work daily in tandem with a microbiologist, finding exactly the right types of bacteria in the houses by smell.

Interestingly, dogs are better at recognizing some smells to one degree or another. For example, the search for drugs is given to them better than the search for the smell of fruit. At US airports, small consignments of fruits and vegetables are prohibited, and only a few animals are able to work in these places, recognizing the smells of apples and carrots.

What affects a dog's sense of smell

Some external factors can affect the quality of smell.

temperature factor. When the temperature is high, the dog becomes lethargic, the body overheats and it does not hear smells well, as it begins to breathe through the mouth. This mechanism has been discussed above. The most optimal temperature limits are from 25 degrees of heat to 15 degrees of frost. At high temperatures, odor particles evaporate faster, and at low temperatures they remain, but the nose can no longer perceive them well enough.
Humidity. At high humidity, odor particles remain in the field of smell. The best weather for a dog can be weather with high humidity. For example, when it rains lightly or fog sets in. But the downpour will wash away all the smells into the ground.
The wind can play both a positive and negative role in detecting a trail. A strong wind blows and disperses odor particles. However, the wind helps the particles to evaporate from the ground and be felt.
Atmosphere pressure. When it is lowered, the evaporation of particles increases and it is easier for the animal to follow the trail.

Also, the sharpness of smell is affected by internal factors. It has already been written about the fatigue of the dog and the loss of the instinct at the same time. The sense of smell is also affected by nutrition. For a good sense of smell, she should receive at least 16% fat. Hunters do not give their pets meat for some time before the next hunt. Its absence in the diet will allow the dog to better search for game.

The sense of smell weakens with age. Of course, even a very subtle cold can also affect the sharpness of the scent. Any anatomical changes in the structure of the nose can affect the flair in various ways.

Turning off one sense organ increases the sensitivity of the other. Interestingly, the best sniffers are cops (this includes all pointers, setters, griffons and others), greyhounds, dachshunds, spaniels and other hunting dogs that have ears that are tight to the head. So far, scientists cannot explain this fact.

Among the watchdogs there are also many representatives with hanging ears (if they were not stopped at puppyhood): the Caucasian and Central Asian Shepherd Dog, Rottweiler, St. Bernard, diver and others. It turns out that since ancient times man noticed this feature and selected dogs in such a way that their olfactory data came to the fore.

Now, based on the data obtained, you can better understand your dog and its behavior. And in conclusion, I suggest watching a wonderful video about the beagle, which helps passengers of the Amsterdam airport to find forgotten things.

Dogs perceive our world differently, and not because they are dogs, but because they feel and touch it better than we do...

Today we will talk about how and with the help of what sense organs dogs perceive the world around them. We really hope that this information will help us get to know our pets better, and many dog habits will become clear to us. So, your dog's sense of smell, sight, hearing, touch and taste...

dog scent

It is no coincidence that when they talk about a sharp sense of smell, they remember a dog, because dogs have the best developed sense of smell and this is no coincidence. The life of a dog is filled with various smells that are constantly changing, intersecting and layering one on top of the other, and in order not to get confused in such a variety, the dog needs a very delicate sense of smell, which will allow him to differentiate different smells and separate such a cocktail of smells into separate ingredients. So, for example, a dog can easily smell one single drop of blood in five liters of water, and differentiate which animal a piece of meat belongs to - a pig, a rabbit or a ram, while it is simply impossible for a person to distinguish by smell whether such meat belongs to a specific type of animal. Well, as for human smells, here dogs have no equal at all - follow the trail, distinguish twins by the smell alone - all this is within the power of our dogs. Of course, sniffer dogs have a special subtle scent, thanks to special training for these animals there is nothing impossible, they can follow the trail of a person, only when this trail is interrupted - the dog is powerless here. It is noteworthy that such a subtle sense of smell is facilitated not only by the presence of internal sensors, but also by the outer part of the dog's nose. So,

in a healthy dog, in order for it to perceive smells, its nose should always be moist, this allows it to absorb smells from the air that it inhales. When an animal becomes ill and its nose becomes dry, the ability to distinguish smells also decreases.

As you know, everything is known in comparison. So, in order to understand how powerful our dogs have a sense of smell, it is enough to know such a fact as the fact that

in humans, the total area of cells responsible for smell is about four centimeters square, while in a German shepherd the same indicator is one hundred and fifty square centimeters !!!

Just imagine this difference. Dogs really sense the world around them with their sense of smell in a different way than we do. Also, a human has five million olfactory cells, while a basset dog has one hundred and twenty five million, and a fox terrier has one hundred and fifty million, and a German shepherd has as many as two hundred million olfactory cells!!! It is no coincidence that pundits claim that a dog senses smells forty times more acutely than a person, and some experts are even sure that in fact, this figure, which determines the degree of sensitivity, is much higher.
As for the special notes of aromas, the smells of fatty acids, which are part of the diet of carnivores, are best for dogs.
Is it possible for a dog to make a real bloodhound out of it? Of course, you can, if you train the animal and deal with it according to a special program. So, for example, if you do not feed a hunting dog with meat before hunting, then its scent will become sharper, and it will be able to take even the oldest trace, which is why hunters prefer to put the animal on a diet before hunting, so it will better capture various smells.

dog hearing

Our dogs also have a very developed way of perceiving the world around them - they hear very well, so well that they pick up ultrasonic waves that the human ear is not able to perceive due to the high frequencies of such vibrations. So, during the war, soldiers very often used this ability of dogs in order to transmit commands to them at a distance that the enemy could not hear. You won't believe it, but

our Buranas and Blizzards are able to hear the sound, the source of which is at a distance of 24 meters, while for a person such a sound limit is only 4 meters ...

But, and that's not all. A dog can distinguish sounds from each other, which at first glance, are no different - if he could speak, he would definitely tell us that different engines of the same brand of car sound different ...

Dog vision

Despite the fact that there is an opinion that dogs see the world in black and white and do not know colors, in fact, dogs have very good eyesight, and at night they see much better than you and me. So, for example, representatives of the German Shepherd breed have a field of view of as much as 180 degrees, and they are able to see the gestures of their master at a distance of several hundred meters!

Touch of dogs

Unfortunately, this area of perception in dogs has been little studied, but even the small amount of information that we have on this subject allows us to conclude that temperature, tactile and pain stimuli are perceived by the skin of dogs and their mucous surfaces in different ways. So, a dog is able to feel the slightest breath of a breeze that touches its fur, which is why, when the air temperature drops, dogs “fluff” their coat, thereby protecting themselves from hypothermia. And, here representatives of northern breeds of dogs can even sleep in the snow in severe frost, and not experience any discomfort.

The scent of a dog is probably its most amazing and interesting ability. The dog's sense of smell allows it to distinguish many smells, including old ones or at a great distance. In this article, we will talk about exactly how this sense organ works, how many smells a dog can distinguish, and how you can test its sense of smell.

Dog sense of smell: general characteristics

Dogs are known to be very sensitive to smells. By smell, your pet is able not only to find food and detect other animals at a considerable distance, but also to determine whether they are familiar or strangers, what gender they are, what their physical and emotional state is. With the help of the sense of smell, the dog distinguishes a huge number of objects and freely navigates the terrain. She constantly smells, and it would be more correct to say - she lives in the world of smells. Animals that rely heavily on their sense of smell are called macrosmatics, and it is to this group that dogs belong. People, on the other hand, belong to microsomatics, that is, we basically feel smells, but in general we are more guided by other senses.
Unlike humans, dogs can smell with a very high degree of accuracy. She is able to sense the presence of one molecule of an odorous substance in 1 liter of air or 1 milliliter of water. It has been established that under favorable conditions, the dog smells at a distance of up to 1 km from their sources, and sometimes even more. If we talk about how many smells dogs can catch, then the figure is very significant. It has been proven that they can distinguish up to 1,000,000 odors.

The sense of smell in dogs is developed at such a high level due to the structural features of the nasopharynx and brain. In particular, in the head of an animal, all odors are clearly differentiated by the slightest distinguishing features. In the mixture, the dog feels each “note” separately, even if some smell is stronger and others are weaker. This already shows how many times the scent of a dog is stronger than a person, because we smell, for example, perfumes or dishes as a whole and are not able to accurately break them down into ingredients, especially if one of them interrupts the rest. Interestingly, the dog not only perceives the smell by itself, but is also able to determine its concentration, strength and freshness. Studies have shown that she distinguishes smells by prescription with an accuracy of 3-5 minutes.

For people, it is of particular importance that dogs easily form conditioned reflexes to smells and their individual “parameters” (strength, prescription, individuality, etc.). This makes it possible to successfully train four-legged helpers and use their excellent flair for a variety of purposes.

Sensitivity to odors

And in conclusion - some useful information for guides of sniffer dogs.

In females, the sense of smell is sharper than in males, but it depends on the estrous cycle (estrogen, like the male hormone testosterone, has a positive effect on it).
Pigmentation of the nasal mucosa affects the olfactory ability. Dogs with light mucosa work less efficiently.
Biological factors can affect a dog's sense of smell (hunger improves it, while poor general health or physical fatigue, on the contrary, reduces it).

The pattern on the nose is unique and individual for each dog, like human fingerprints, the pattern of which never repeats. Animals are identified by the pattern on the lobe.

The color of the nose in dogs depends on the color of the coat. So, for example, in individuals with white spots on the coat, the nose may be spotty, in red individuals the pigmentation is brown. But under the influence of external factors or diseases, pigmentation disorders of the nose are possible.

Nose of a healthy dog

It is generally accepted that the humidity of the nose can be judged on the state of health of the pet. A wet nose is a sign of good health, while a dry one signals possible problems, which is erroneous. The moisture in a healthy dog's nose can fluctuate throughout the day. Weather conditions, changing room temperature can be the causes of dry nose lobes. In addition, there are a number of other reasons why the lobe becomes dry, but not related to the pet's painful condition. So, for example, a dog's nose can become dry after a long stay of the animal in the sun, being near a heat source (fireplace, radiator), staying in a poorly ventilated room, with insufficient water consumption.

Of course, a dry nose can serve as one of the symptoms of a disease, but often diseases are accompanied by other symptoms, such as peeling, redness (sunburn) of the ear, and discharge.

Factors affecting the sense of smell

Despite the fact that dogs are considered to be among the best sniffers, there are many factors that can affect their sense of smell, which can either improve or worsen it. Let's look at the most common causes of differences in olfactory abilities in dogs and how to correct them.

Let's start with climatic conditions, which have a significant impact on the dog's sense of smell. With increased humidity and precipitation, the sense of smell worsens, as there are additional irritants and extraneous odors emanating from water and earth. It is because of this that it is so difficult for dogs to follow the trail in rainy weather or in bad weather conditions.

The next factor is air temperature. It would seem that how it can affect the sense of smell, but, in fact, the performance of the animal and its olfactory capabilities depend on the temperature. The temperature factor directly affects the condition of the dog's body. In extreme heat and high temperatures, the animal quickly gets tired, becomes lethargic, and its breathing quickens, which is why odors cease to be so sharply distinguished. In addition, elevated temperatures accelerate the volatilization of odors, which significantly weakens their strength. At low temperatures, on the contrary, odors persist much longer, however, during severe frosts, dogs also experience difficulty in taking a trace due to freezing of water particles on the mucous membrane.

The food that a dog eats also directly affects its sense of smell. Food that has a too strong and pungent odor can discourage the animal from smelling, and the longer the dog eats it, the weaker its scent will become. Odors such as herring, onion and other pungent odors should not be present in the animal's diet. The sharpness of the scent also depends on the type of meat. So, for example, lamb, and even lamb bone, can take away a dog's instinct for a long time. Therefore, you should be very responsible in choosing food for your pet.

Do not forget about the differences between dog breeds. Some of them have a more pronounced sense of smell, and some of them are slightly dulled. It is the breed that often determines whether a dog is suitable for search work or not. Some breeds have an innate ability, laid down at the genetic level, to take a trail and lead it, you just need to be able to develop it correctly.

How to keep the scent

In order for the dog to distinguish smells well, it should not be tired. An exhausted and lethargic dog distinguishes smells much worse and is not able to react sharply to their changes and interruptions. But, in addition to general fatigue, there is also olfactory fatigue. When walking for a long time on the trail and inhaling odors, the sense of smell is slightly dulled, in order to restore it, the dog must be given a little time to rest by placing it in fresh air and not giving any tasks to search for objects. Do not forget about the proper care of the dog's nose, the condition of which directly affects the quality of the scent. Under normal conditions, the surface of the nose should be damp and cold; it can only be dry when the animal is sleeping. If your pet is sick or overtired, his nose will become dry, this will be a signal to take appropriate action. The animal must be taken to an appointment with a veterinarian, who will find out the cause of the disease and prescribe the appropriate treatment. A wet nose allows the dog to absorb odors from the air, and in the absence of moisture, the ability to distinguish odors is significantly reduced and the sense of smell decreases.