Why dogs smell their butts


Surely many times you are walking on the street and, when you have encountered a lot of dogs that cross and smell your butt have you asked yourself:why dogs smell each other? Although this custom is not very hygienic or pleasing to humans, the answer is more complicated than you think and is about "chemistry."

If you want to know why do dogs smell each other Do not miss this article of Animal Expert where we will explain in detail the reasons that dogs have to always follow this ritual when they cross with others of the same species.

Secret Revealed: Chemical Communication

Although seeing two dogs sniffing the anus is not a very comfortable situation for the owners, the truth is that this is how the dogs collect all personal information of his other canine companions. From age, gender, what they have eaten, the breed, or even the mood of their homonyms, dogs are able to gather all these data by sniffing from behind.

And it is that unlike humans, who have a sense of smell far less advanced, man's best friends (as they are often called) have the sense of smell between 10,000 and 100,000 times more developed than we are. So, when a dog is sniffing another's butt with its snout, what it is doing is collecting the necessary information to get to know its canine companion better and thus be able to properly socialize with it. This is called "chemical communication", a term coined by the Chemical Society of the United States (ACS), which discovered that dogs related and communicated through the chemistry that their bodies give off with odors, like many animals.

The anal glands and Jacobson's organ

What is the reason that dogs can collect all that information just by smelling their partner's anus? The answer is the anal glands. These sacks or anal glands are two small bags that are located one on each side of the anus of the animal and that contain all the chemical information of the animal through the secretions it produces.

In 1975, Dr. George Preti, chemist at Monell Chemical Senses Center from the American state of Philadelphia, he studied the secretions of the anal glands of coyotes and dogs, and discovered the main chemicals and aromas that made them up. Thus, it turns out that the chemical communication pathway of these animals is a compound consisting of trimethylamine and various fatty acids, which allows through its smell, to know the genetics and the immune status of them. In this way, each dog gives off a characteristic smell because each one has a certain diet and a different immune and emotional system.

In addition to the sense of smell, dogs (like many other vertebrates, such as snakes) have a auxiliary olfactory system, and is the Jacobson organ or vomeronasal organ. This member is located between the nose and mouth of dogs, specifically in the vomer bone, and thanks to its sensory neurons that send the information collected directly to the animal's brain, it is able to detect different chemical compounds, usually pheromones. So dogs are specialized in smelling the anal glands of their partners and thus being able to recognize your emotions and your fitness.

Smell and olfactory memory

The most developed sense of dogs, as is well known, is smell, which is 10,000 times more sensitive than their sense of taste, for example. Because they are born blind and deaf, newborn puppies already use it because they need to find the mother's nipples smelling them in order to feed. Once they grow up and become adults, dogs have between 150 and 300 million odor receptive cells (compared to 5 million humans) and this makes them experts in detecting all kinds of aromas. Therefore, these animals are used as people search dogs, explosives detection, drug tracking, or even for the detection of diseases in humans. In addition, the sense of smell has a function very important for reproduction of the dogs and is that when the females are in heat, their glands give off certain pheromones so that the males know that they are receptive.

Apart from being the most developed sense, dogs also have a very effective olfactory memory and they are able to remember the smell of other dogs, although they have not seen each other for years, thanks to the fact that they smell each other as usual whenever they meet again. Its olfactory area reaches 150 cm2, while the area of ​​humans is 5 cm2, so they will always use smells to recognize and remember us and other animals.

If you want to read more articles similar to Why do dogs smell each other?, we recommend that you enter our Curiosities section of the animal world.

Secretions Dialog

In 1975, scientist George Preti, an expert in pheromones and human odors at the Monell Center for Chemistry of the Senses, studied the anal secretions of dogs and coyotes and identified the main components of the secretions produced by the glands housed in two small bags called sacs annals.

This chemical language, Preti observed, is composed of trimethylamine and various volatile fatty acids, and the aroma can change according to the animal's genetics and immune system.

But also, the interesting thing is to know how dogs do to perceive and process this chemical "message".

The dogs, the ACR experts explain, have an auxiliary olfactory system called the Jacobson or vomeronasal organ.

Designed specifically for chemical communication, this organ has its own nerves that communicate directly with the brain.

Therefore, there is no interference from other odors and Jacobson's organ can engage without distraction to read the chemical "business cards" of his dog friends.

Other experts in smelly messages

The dogs are not the only ones that communicate with smells. Nature offers numerous examples, here we tell you a selection of the most curious:

The perfumer:

The sack bat is an expert in the art of chemical communication that not only secretes but mixes aromas to attract females.

These animals live in harems divided colonies, each with a male and several females. Males mark their territorial domain with secretions from a small gland called gular located under the chin.

But to woo the ladies, a single smell is not enough: it is necessary to mix this secretion with others produced by their genitals and urine, which the males carefully prepare each day in special sacks they have on their wings, such as explains Jason Goldman of BBC Future.

Although the result may be stinking for human smell, the "perfume" of these bats requires a complex process that will then emanate to seduce her, thanks to a timely beat of wings in front of the female.

The black antelope and its powerful aphrodisiac:

This mammal that lives in India, Pakistan and Nepal, has a curious, and certainly odorous, method to attract the attention of females.

In addition to the aroma secreted by their tear glands during the mating season, males communicate their intentions with their droppings.

Instead of chasing the females, the antelopes produce a lot of feces and wait for them surrounded by this peculiar aphrodisiac smell, a strategy that was recorded by BBC Nature.

The aromatic weapon of the ring-tailed lemur:

These primates of the island of Madagascar have a strange way of fighting over the territory: the males rub their tails with small glands that they have on their wrists and then shake it to spread the aroma.

It's deployment is usually enough to mark the hierarchy, although sometimes you can't avoid close combat.

In addition, shaking the "scented" tail also serves to attract females, according to BBC Nature.

Related news

It is probably not a question that takes our sleep away but the explanation of why dogs sniff each other's back has a very complex explanation. Generally, this action causes rejection and more than one owner tries to separate his pet to avoid that a priori recognition unpleasant to the eye and apparently unhygienic.

However, it is, as the American Chemical Society notes in a didactic video, an important "chemical communication." When dogs do they are collecting very valuable information about the characteristics of their canine companions: so they can know the diet, gender and even the emotional state of dogs. "Chemical communication" is very typical in the animal kingdom and is not only produced by sniffing "the back."

Keep in mind that dogs have an exceptional sense of smell. To give you an idea, his nose is between 10,000 to 100,000 times more sensitive than that of the human being.

But how does this curious process of "data collection" occur? What chemicals are involved? On each side of the anal ring (anus) of dogs, there are two bags called anal sacs that excrete the chemicals that dogs use to obtain information. The apocrine sweat gland is most responsible for what dogs smell but also the sebaceous gland plays a role in this process.

George Pretti of the Monell Chemical Sense Center in Philadelphia discovered that the main chemical compound that produces dogs 'aroma' is trimethylamine in addition to a series of short chain acids.

When dogs sniff the secretions of this anal sac, the information they get is very accurate. However, genetics, diet and the immune system produce chemical changes that cause the smell to change.

Jacobson organ

As if this were not enough, dogs have a second system of smell thanks to the so-called "Jacobson organ" (auxiliary organ of the sense of smell in some vertebrates) specifically designed for "chemical communication." The organ is also used when dogs mark territory with urine.

See TopComparatives

Hi, !

We want to meet you to be able to offer you the contents according to your preferences, could you answer some brief questions?

It will not take you more than a minute.
Thanks in advance!

Accept Now we don't want to meet you 1 2

Please can you give us your date of birth and gender?

We want to meet you 1 2

Please mark one or more topics that interest you.

Accept Skip this step We want to meet you

Why do dogs smell their asses?

Dogs have a very personal smell in their anus, due to a liquid released by their anal glands. This smell is unique, in the same way that fingerprints are in humans. So each dog has a completely different smell than the smell of other dogs, a totally personal smell.

Dogs can know thanks to that smell many things the dog is smelling the butt. They can know their approximate age, the type of nutritional diet they have, the mood and even the health status of the other dog, among many other examples.

Letting you smell and smell your ass is a fundamental part of socialize a dog correctly, it is a fundamental and essential form of communication between dogs (remember that they have the smell thousands and thousands of times more developed than humans).

We must never prevent our dog from sniffing the tail of another dog, nor should another dog smell the ass of ours. It is a completely natural and necessary act among dogs.

Why do dogs smell their parts?

In addition to oiling the anus, something that is completely habitual and normal. Dogs also usually smell their intimate parts, their genitals. The genitals of a dog also provide an odor on it, so that other dogs can get even more information simply by sniffing a little.

The urine of a dog leaves a very characteristic smell that other dogs easily identify, it is not a smell as personal as that of the anal glands, but it is also quite personal.

In this way if our dog smells the genitals of other dogs, you can know if he has urinated somewhere he has walked, if it is a female or a male, if he is in heat if he is female, if he is sick, etc. ...

It is something completely normal and natural, even sometimes they suck a little, to further increase the smell and in some way, savor it. Dogs communicate like this and we shouldn't bother them when they do, it's their way of communicating.

Your dog smells other dogs' butts to get to know them better

Several studies have been conducted to determine what type of substances are released in the anal areas of dogs to determine what are our dogs smelling. Around the anus of our dogs are glands that form the anal sacs. In this area there are different types of glands, and although all are responsible for the smell, the most important in the apocrine gland.

The apocrine gland is responsible for secreting the chemicals that dogs use to know each other. After analyzing the anal secretions of different dogs, the primary chemicals that form that ‘dog smell’ have been identified. The main substance is trimethylamine, but a series of short chain acids such as valeric acid, acetic acid, propionic acid and butyric acid are also part of that smell.

The dog's sebaceous glands also play a very important role in its smell. But as you can imagine, the anal sacks of a dog have a powerful smell thanks to those acids it releases. But nevertheless, that smell is modified according to the genetics, diet and emotional state of the dog. And all these changes, are the ones that our dog is able to detect while it smells the butt of his new playmate.

So you know, you can stop thinking that your dog has no manners, and convince you otherwise. Why when your dog smells another dog's butt is knowing him in the best way he knows, through his nose. By the way, did you know that your dog understands you more than you think?

Dogs smell to receive chemical messages

Woulda kind of source of information through chemistry. This would be one of the many examples of chemical communication in the animal kingdom.

When dogs smell,they activate an auxiliary olfactory system called Jacobson's or vomeronasal organ. This organ has a lot of chemical communication capacity. Your own nerves communicate directly with the brain.

Where does the information come from?

Dogs smell and receive a lot of information. Where is it contained? On each side of the anus of our pets there are two bags called anal sacs that excrete the hairy chemicals used to obtain information.

The main responsible for the transfer of all these data when two dogs smell, is theapocrine sweat gland. The sebaceous gland also plays an important role in this process.

It also happens that When the dog grows, the anal glands can cause problems. Many times the stool enters these glands and can be annoying and even painful for the hairy. If we observe that the animal is dragging its ass on the ground or trying to look a lot at the anus, it is time to go to the veterinarian to clean these glands.

You have to know that our dogs sniff secretions in the anal sack of others of their kind, and thus obtain very accurate data. But we will also keep in mind that genetics, diet and the immune system produce chemical changes that cause the smell to change.

The moment of the walk and the social coexistence

When we take our dog for a walk and meets another, the ritual begins: a fearful approach, tail movement or alert attitude and, immediately, the respective back and forth joint. For those who have never had a hairy, this behavior borders on depravity and rarity.

This behavior that happens when dogs smell, is natural and everyday. We should not repress our pet for it, but we will try to understand why it happens.

Although it bothers us a little, It is good that we allow our pet to sniff for a few seconds to other dogs so you can develop your chemical communication at ease.

Smell and memory

Since they are born blind and deaf, the puppies already use their sense of smell, among other things to find the mother's nipples smelling them so they can feed.

When they grow up and become adults, dogs havebetween 150 and 300 million odor receptive cells. If we compare it with the 5 million of these cells that we humans have, we will see the difference in the olfactory aspect.

For all this, the dogs are usedsuch as people search dogs, explosives detection, drug tracking, or even, for the detection of diseases in humans.

Too the sense of smell has a functionvery important for reproduction of the dogs. In this way, when females are in heat, their glands give off certain pheromones so that males know they are receptive.