Encyclopedia of Pets. Dog's sense of smell (scent) and testing it

This is a kind of illustrative protocol: the faces of couriers, packages with drugs, places where they tried to hide them. Most of the drugs, the specialist says, are now transported by rail: carriers are attracted by all kinds of niches in the carriage. At the same time, they have a better chance of disowning dangerous goods.

At our site, work today, as a rule, is transported from Ukraine to Russia. Usually these are soft drugs - marijuana, - the specialist explains along the way.

Favorite directions - Nikolaev - Moscow or Crimea - Moscow. In the Russian capital, both demand is higher, and the price difference is more significant. And why the “products” come from there - because the quality of the “grass” directly depends on the southern heat and the sun.

You see, we are already talking about this as a kind of criminal business, ”the customs officer states sadly. - By the way, the "farmers" themselves with their "goods" no longer run around. 95% of those detained are couriers. It is more profitable to work with them, they know little, because they are involved only once or twice. As a rule, these are people with very low incomes, on the verge of poverty. A typical legend of a drug courier: a pensioner or an elderly woman is bringing home gifts for children to Moscow - lard, vodka, potatoes. And under these products - several kilograms of straws.

Addict couriers can't hide

But there are also young couriers. Dmitry Nesterenko recalled a case when a 21-year-old girl was transporting acetylated opium to Moscow.

A novel about this would be snapped up, - the customs officer admits. - The girl is beautifully dressed, good-looking and - "high". We started talking. It turned out that she did not remember her father, her mother lived with someone else, and her grandmother had raised her since childhood. I had my first injection when I was 16 years old. Before that, she worked with relatives in Moscow and returned to her hometown with a significant amount of money. Friends immediately flocked, one even assured of his love. Apparently, out of a deep feeling, he suggested to his girlfriend to inject together. The Moscow relatives, having learned about this, immediately took the girl to her place. But two years later she had to return - her grandmother felt bad. And everything went on in the second round.

Dmitry Nesterenko shows another photo. A girl of undetermined age with a rumpled face looks angrily into the lens. Right in front of her is a bag of marijuana, which she tried to smuggle across the border in her travel bag.

And in the photo in the passport just a year ago - an incredible beauty! - the customs officer is surprised. - Couriers - drug addicts are usually not resourceful and hide their cargo in the most common places: in the luggage compartment or behind the battery bars by the window.

Favorite stash - socks and diapers

"Sober" carriers are more original. For example, they open a Tetrapak package of wine or juice, empty it by half (so that it gurgles) and put the "product" in it. The top is sealed so skillfully that even the control marks match.

Or another case. In the conductor's compartment, the dog gave a signal. She was clearly worried about the transfer that the train employee was asked to give at the station. The package was opened, there is a beautifully wrapped gift - a plush monkey and a touching postcard: “To my dear son for his birthday. With love, mom. " But the guys still trusted the dog and opened the toy. Indeed, there was a drug in it.

And once customs officers found a potion in a pack of cookies called "Pleasure Life". Couriers also turned out to be jokers. But the most common place is dirty things, which are not pleasant to touch. For example, once a dog smelled a familiar smell in used socks, which a passenger tucked under the pillow. There was a case when 84 grams of the drug was found in used diapers.

To this topic

Service reward - toy

In addition to "guardianship" over potentially criminogenic trains, law enforcement officers and SBU officers direct the customs officers to the trail of drug couriers.

We have close cooperation, - Dmitry Nesterenko explains. - And our main helpers are service dogs, the Labrador Bundy and the Doberman Shakira. They smell the drug from the doorway of the carriage. It is not without reason that our cynological teams are one of the best in Ukraine.

For good service, we spoil them with cookies, - admitted the head of the sector. - But most of all they are happy with new toys, mere children.

Each person at least once in his life experienced the aggression of a dog towards him. Why do a person's friends behave aggressively? The answer is simple: the animal always reacts to the fear felt by the person. But how does a dog know that we are afraid of it?

Debunking the adrenaline myth

For a long time, among ordinary people and even among professional cynologists, there was a myth that a dog attacks because its sensitive sense of smell picks up changes in the smell of the human body under the influence of adrenaline. After all, fear is always accompanied by the release of adrenal hormone into the bloodstream. It is even called the "fear hormone".

However, a series of experiments conducted in 2014 at the cynological department of the Perm Institute of the Ministry of Internal Affairs convincingly proved that a change in smell does not affect the manifestation of aggression, although it is obvious that dogs are able to smell an increased level of adrenaline in the blood.

Eight dogs of service breeds (German and Belgian shepherds, and one hybrid of a wolf and a dog) took part in the experiments. A total of four series of experiments were performed.

First, one of the participants in the experiment hid a cotton pad dipped in saline (this is ordinary table salt diluted in water) in a sleeve.

In the second series of experiments, adrenaline was added to the saline solution. Then the disc was soaked in sweat secretions from a frightened man, and, finally, during the last experiments, one of the volunteers was injected with adrenaline.

All dogs during the experiments successfully found the owner of the disc among the other participants in the experiments. So it is safe to say that the dog's sense of smell is very acute and dogs perfectly distinguish the adrenaline "aroma". But, in none of the cases of aggressive behavior of the animal towards the subjects, on whose body a cotton disc soaked in various substances was hidden, was not observed. The emotions of the four-legged test subjects were limited to curiosity and bewilderment. The dogs also tried to be careful, to ignore the person who exudes the smell of adrenaline.

Thus, the researchers concluded that the smell of adrenaline is recognized by dogs, but it is not a marker of fear for them. The dog perceives elevated levels of adrenal hormone as a sign of anxiety, but not as a signal to attack. In canine perception, adrenaline does not equal fear.

How does a dog know when they are afraid?

An additional series of experiments was performed to determine how the dog feels fear of others. Volunteers demonstrated fear through facial expressions, gestures and behavior. Moreover, in half of the cases, the participants in the experiment were given adrenaline injections, and the other half simply imitated fear.

In both cases, the aggressive behavior mechanism was triggered in the dogs. The aggression of animals did not depend on the presence or absence of the smell of adrenaline. The trigger was exclusively the behavior of the subject - a natural scientist, a visual "picture".

Dogs are very observant. They sense our fear by the pattern of body movements, by the expression on our face, as well as by our voice. And this is very good, because if we cannot control the "fear hormone", then we are quite capable of controlling our face.

Therefore, in order not to become a victim of an attack, it is necessary to maintain external calmness. Smooth, confident movements, a neutral facial expression, the absence of hysterical notes in the voice - all this will help you stay safe and sound. You can be afraid, you can not show it! After all, the dog does not feel our fear, it sees it.

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

Dog's sense of smell: general characteristics

Dogs are known to be very sensitive to odors. 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 his sense of smell, the dog distinguishes a huge number of objects and is free to navigate the terrain. She constantly smells, and it would be more correct to say that 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, are microsomatics, that is, we, in principle, smell smells, but in general we are more focused on other senses.

Unlike humans, a dog smells very accurately. She is able to sense the presence of one molecule of odorous substance in 1 liter of air or 1 milliliter of water. It was found that under favorable conditions the dog smells up to 1 km from their sources, and sometimes even more. If we talk about how many odors dogs can pick up, then the figure turns out to be quite significant. They have been proven to distinguish up to 1,000,000 odors.

Scent in dogs is developed at such a high level due to the structural features of the nasopharynx and the brain. In particular, in the head of an animal, all odors are clearly differentiated according to the slightest distinguishing features. In the mixture, the dog senses 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, perfume or food in general 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. Research has shown that she distinguishes odors by age with an accuracy of 3-5 minutes.

For people, it is of particular importance that conditioned reflexes to smells and their individual "parameters" (strength, age, individuality, etc.) are easily formed in dogs. This makes it possible to successfully train four-legged assistants and use their excellent instinct for a variety of purposes.

How a dog's sense of smell works

Considering what an accurate sense of smell our pets have, it is interesting to understand how a dog's olfactory organ works and how it works so well. In general, the sense of smell of a dog and a person functions according to the same scheme. Special receptors located deep in the nasal cavity capture molecules of various substances in the air and form the sense of smell, transmitting them to the brain. These receptors form the olfactory epithelium, and in dogs, its area is 250-400 square meters. cm (for comparison - in humans it is usually about 7-10 sq. cm) and consists of 125-224 million olfactory cells. Moreover, he the epithelium layer of our pets is 15 times thicker than ours... Each such cell has a large number of thin cilia, which greatly increases the olfactory ability. All this provides a high sensitivity to the smallest particles of odor substances in the air.

At the same time, a dog is much better than a person, able to regulate the sensitivity of its olfactory system... First, it controls the nostrils more efficiently. Second, it can alter breathing to better smell. Usually, only about 5% of the inhaled air passes over the olfactory epithelium, and more than half of the odorant is simply absorbed in the nasal cavity. Therefore, when the dog is faced with the task of sniffing, he takes deeper breaths or several short ones in a row.

In the olfactory region, the molecules of odorous substances come into contact with the villi of the olfactory cells and enter into physicochemical reactions with the membranes of the corresponding neurons. Depending on the smell, these reactions are of different frequency, strength, amplitude and duration. These parameters are delivered to the nerve centers of the olfactory zones of the temporal lobe of the cerebral cortex. The so-called olfactory brain is located here, which analyzes the information received and forms certain smell sensations, which are associated with their source. Thus, the dog remembers not just the smell, but the scent image.

Dog flair: bottom and top

As we know, dogs can easily determine the presence of footprints of another animal or person, understand in which direction the footprints lead, and follow them. But how does this process take place? Having found the trail, the dog, sniffing, crosses it several times, as if making a "figure eight". Such movements allow her to compare the freshness, intensity and direction of displacement of odor particles of the trail and soil. As a result of the analysis, the animal understands how long ago the trail was left and in which direction it leads. Next, the dog begins to move, tilting his head down and following invisible scent prints on the ground. Respectively, this kind of instinct is called bottom.

A completely different behavior is characteristic of an animal that smells an unfamiliar smell or is studying the environment. In such situations, the dog usually lifts its muzzle upward and vigorously draws in air, turning its head and body against the direction of the wind. These movements help to capture the odor particles brought in by the air currents and determine the source of the odor and the distance to it. This flair is called the upper, and the very ability to catch a smell at a distance - by the range of sense. How many meters a dog will smell this or that smell largely depends on a number of factors: on the source itself, on environmental conditions (extreme cold and heat, like rain and fog, interfere with the sense of smell).

Dog flair: adaptation issues

Everyone is familiar with the situation when, entering the room, we felt any strong smell, and after a certain period of time we stopped feeling it. Scientifically, this process is called olfactory adaptation, that is, it is the ability of humans and animals to adapt to the perception of various smells. The considered example is a case of negative adaptation. Since the smell in the room was very strong, the brain began to simply ignore it, so that it did not interfere with us "working" with other smells.

This principle is equally true for humans and dogs. But if for us negative adaptation does not pose any particular problems, then for animals it can lead to the fact that they simply cease to sense the trail. As a rule, the dog begins to ignore the smells of the same concentration when he quickly follows fresh tracks and does not break away from them. To avoid this, animals are taught to follow the trail in a zigzag pattern(by shuttle). So the desired smell becomes stronger, then weaker, and negative adaptation does not occur. If you want to train your dog to follow the trail, keep this feature in mind and teach your pet to move not directly on the trail, but as if to wag around it.

We add that, in addition to negative adaptation, there is also a positive one. It is understood as a process when the sensitivity of the receptors, on the contrary, increases, which makes it possible to capture the minimum doses of an odorous substance and work with traces of a long time ago.

Dog Scent Test

A professional test of smell is carried out when selecting dogs for various cynological structures, where such a unique sense of smell is very useful. In particular, the search, search and rescue, mine-search services are glad to see dogs. Dogs work in teams for the search and detection of drugs, explosives, weapons, ammunition, etc. In such cases, testing of smell and selection of suitable animals is taken with particular seriousness. However, an ordinary owner does not set such important tasks for a four-legged friend and can conduct a less complex test even at home, partially replicating the techniques of professionals.

The simplest way is placement in different places on a plot of 25 x 25 meters 5 pieces of meat... By the fact whether the dog can find all the pieces and how quickly it does it, they judge its sense of smell. Several important conditions: there should be no other strong odors in this area, and the dog and its owner should not be able to peep where the pieces lie.

Another way available for repetition in everyday life is testing the ability to locate and select a small aported item from a large number of similar items. To do this, you first need to teach the dog to find and pick up a thing thrown in front of her in the grass or low bush (this is necessary so that she does not look for an object with her eyes, but switches to the sense of smell). Then, already directly during the scent test, in full view of the dog, a small object that has the smell of the owner or assistant is thrown into a pile of objects of the same size and color. When dogs are tested by dog ​​handlers, the total number of items usually goes up to 50-60. An animal is assessed by its ability to find what it is looking for, as well as by its search activity in general. If the dog does not show any interest in the process, subsequent training will most likely not bring the desired results.

Another way from the arsenal of employees of the search services - test of the ability to detect the odor trail. Practice shows that some animals can find a thing by smell, but they are not able to take a track and follow it. For such a check, two assistants lay two tracks with a difference of 25-30 meters. In this case, the second assistant before this rubs the shoes with meat or sausage or ties the pieces to the sole.

The trainer brings the dog to the first scent trail, releases it for a walk and observes its behavior. Most dogs with a developed sense of smell immediately react to smell: sniff, determine the direction of movement and attempt to follow the trail. If the animal has not reacted in any way to the first trace, it is directed to the second. If in this case the testing fails, then such a dog is not suitable for the search service. If you have a puppy or young dog, you can also repeat a similar experiment: make a trail yourself and see if your pet can take it.

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Now let's talk about whether the dog can feel pregnancy or? It is unlikely to determine the gender, but to feel it completely.

Although the beloved pet does not understand that after 9 months he will have to share the love of the owner with the tiny person, there is a possibility that the dogs feel the woman's pregnancy. Chances are, your furry friend knows change is coming - sometimes even before you know it. And although there is no scientific confirmation of this guess, there are still a number of reasons to consider it quite legitimate.

A discerning dog's scent is able to catch the slightest changes in the smell of his mistress, which occur due to a jump in hormone levels during pregnancy.

The behavior of the dog during this period can also change significantly in relation to the owner. It is typical for dogs to go into combat readiness and overprotection from the very woman. There were times when the dogs began to growl, bark or close the door with their bodies, preventing anyone from entering the room with the expectant mother - even the husband.

How Dogs Feel Pregnant Women

Dogs Feel Pregnant Woman

So, some of the changes that a dog can "smell":

Language of the body: During pregnancy, you not only start to look different, but also move.

Behavior: dogs know how to feel the mood of the owners, so they can easily notice the emotional changes associated with pregnancy

Chemistry: the level of hormones is off scale, which means that the body odor changes. Thanks to their unique scent, dogs are able to smell the slightest change in odors.

Now that you know if the dogs are feeling the owner's pregnancy, try to be more attentive to your pet. Indeed, like people, they may have different reactions to the future appearance of a child in the family. When a dog begins to notice changes in mood, posture, smell, and daily habits, it may begin to act like it’s been forgotten. Help your dog understand that you still love him and be careful about how you behave. For example, when a pregnant woman places her hands on her belly, the dog may think that this closed hand position means "No, move away."

I usually cross customs barriers without undue concern, although I often raise the suspicion of the clergy of the striped gate. For example, when crossing the demarcation line by train or bus, out of fifty travelers, it will be me who will be forced to get out of their luggage and gut the suitcase. And at airports, it is my wearable gadgets and survival devices that cause a lot of admiring bewilderment of employees, and the playful palms of girls in white silk gloves strive to touch my innermost nooks. And even frames in supermarkets are falsely working for me. But, since my conscience is clear, I react to such tricks, as a rule, with a fair amount of humor. But this time it was different.

Having learned where I was flying, one aunty acquaintance asked me to give her daughter, who lives and works in those parts, some gifts - from those that she would not buy for herself either because she was not in local stores, or out of natural modesty. There were three items, and everything was either outright contraband. or subject to mandatory declaration and running on the red carpet. The most harmless of them was the golden zodiac pendant. Further - dried roach, to beer; there is no unequivocal conclusion on this in the customs rules, but on hints - they can, if desired, prohibit transportation, especially to the Schengen area. And finally, weed; yes, such a democratic mother - she knows that her daughter loves to indulge in botany and passes it on.

I, of course, immediately warned that all transmitted objects can be filtered at the border. Well, he took appropriate measures. For example, I took the pendant out of the factory packaging, cut off the tag and attached it to the keychain; although at the slightest check it is easy to find out that I am never a scorpio, but a capricorn. But I put the roach and the weed in my backpack; on top - to quickly throw off at the first hint. I also wanted to back it up with signed papers, but abandoned the idea - the fact is that everything was laid out in separate packages, placed in one big one; and at home I took out these bags with gloves so as not to leave my prints.

And now - Sheremetyevo, green corridor, hello, border ...

The troubles began immediately at passport control. At first, sincere. Those who have flown know that there is such a grounding thing in the form of dividing control into "Passport Control" and "Passport Control for Russian Citizens." And, stsuko, in the last such Soviet line in three rows. Yeah - know, it was, there was a place ... After waiting for my green arrow, I go in, hold my passport through the slot and see how the stern uncle hangs behind the glass. In short, unlike others, my passage took five times longer: the border guard peered at me ten times, checking my passport; and every time, thinking that he had difficulties with this, I changed my expression. Then one of those who followed me asked - what happened and why did I grimace like Louis de Funes?

But then there was a complete tsimes. It turned out that of the two frames, only one worked, which brought a sickly headache to the employees (according to them, the second one broke down at night, but the workers had not yet appeared with repairs). And the whole crowd, like rams, was chased through the remaining frame at an accelerated pace. Nobody dug, did not feel - they just asked to quickly pull out of the inspection zone. They didn't even take off their shoes, belts and watches.

Not believing my luck, I grabbed my backpack and stomped to look for my gate and admire the airplanes.

So, if you suddenly decide to take a vobla or weed there, don't worry, because the scanner knows its business, trained by specially trained people for goodies, and therefore easily distinguishes marijuana from a mixture of thyme, oregano, mint and currant leaves.