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Why Do Dogs Sniff Butts? {And How It Might Save Their Life!}

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Do you wonder why–every time your dog meets another dog–he zooms in for that embarrassing sniff? We’ve reached out to the experts for answers–and they just might surprise you! Not only is your dog exercising what’s nearly a superpower but he’s also performing an act that just could save his life!

You know the drill. You’re out walking, and your dog spies another dog. Soon they meet and, just as you expected, your dog zooms in for the old butt sniff. While he sniffs, the other dog sniffs your dog. What’s up with that–why do dogs sniff butts?

The short answer: your dog is after information—and that’s exactly it’s found.

Why Do Dogs Sniff Butts of Other Dogs?

Dog’s Sense of Smell vs. Human’s

The dog’s sense of smell is about 100,000 times more sensitive than people,” explains Gaylord M. Brown, Jr. DVM. “This is because they have around 220 million olfactory receptors while humans only have around five million.

“They also have a special scent organ, the vomeronasal organ, that enables the dog to better detect pheromones. Pheromones are chemical communicators that can convey mood, sex, willingness to mate or fight, and a myriad of other information.”

Dr. Brown, the in-house vet for the past 30 years at California’s D.E.L.T.A. Rescue, explains that “when a dog sniffs another dog, they are finding out where he has been, if they are friend or foe, potential mate, and even what they have been eating lately. With this information, they are able to decide how to interact with this new dog or tell them what a familiar friend has been doing.”

Butt Sniffing is a Sign of Good Dog Manners

butt sniffing is good manners between dogs

The behavior that many dog owners find embarrassing is not only perfectly normal dog behavior but also a sign of good manners.

Like shaking hands, the sniff serves as a way to show friendly intentions, as compared to a face-to-face confrontation. What we find an embarrassing display is actually proper etiquette in the dog world.

Not all dogs understand the benefit of the olfactory introduction as compared to a face-to-face greeting. Our dog Tiki, for example, often rushes to greet other dogs nose to nose rather than the better mannered (and far safer) nose to tail greeting.

Dogs that were removed from their litter too soon (Tiki was a stray so we don’t know her early background) and don’t learn proper manners from their mother may not realize the polite greeting is nose to tail.

Why Butt Sniffing May Save Your Dog From a Fight or Even Save His Life

sniffing butts helps dogs avoid a dog fight

The nose to nose greeting puts dogs at risk of a bite, exactly what they’re trying to avoid with a posterior sniff that serves not only as a source of information but as a survival tool.

Dr. Jeffrey Levy, a holistic vet and pet expert in New York City, also points out that their strong sense of smell – including its use in receiving information from another dog’s anal glands – helps to avoid unnecessary fights.

“Dogs use their sense of smell to find food and stay alive. They can identify potential prey and avoid predators. Humans have harnessed the canine olfactory senses in hunting for eons.

“More recently, we utilize these abilities in dogs to find explosives, predict seizures, locate the injured, sniff out contraband, identify bed bugs, and much more.”

Why Do Dogs Sniff Human Bottoms?

That’s all fine and good; you’re OK when your dog sizes up another dog. But what about when a dog sniffs a human?

We all know the embarrassment of stopping to greet a friend—only to have our dog suddenly nosedive toward her crotch or rear end.

Just as when your dog seeks information from another dog, he’s sizing up humans as well with the sniff.

According to Dr. Brown, “Basically, a dog sniffing a human will convey the same information to the dog. If it is their friend, smelling will determine the mood of the person and help them to know how to interact.

If it is a new person, the odors will determine if the person is dog friendly or afraid of dogs. The dog is also able to determine if other dogs have been in their human’s path that day!

And while we try to cover up our own body odors, the truth still lies among that pool of deodorant and perfumes, at least to the unparalleled nose of the canine.

“We humans are always trying to cover up our scents, from bathing every day to adding deodorant and colognes. We only want to smell good stuff, and we even find ourselves making faces if something smells bad,” explains pet psychic and animal communicator Terri Jay.

Jay points out that we have many ways to communicate with others—from words to gestures—but our dogs rely on those scents.

“While pets do have postures and expressions which can be read by other animals, their main source of information about the other animals and most of the things in their environment is their sense of smell.”

So, the next time you see your dogs sniffing another dog or a friend, think of it much like a canine computer search.

Your dog is tapping into a database of information that, while it may be unseen (and, thankfully, un-smelled) by us, is nonetheless a source of important data.

Like so many remarkable talents and skills that our dogs possess, that sense of smell is one of many facets of our dogs that makes them so special.

Pin it to remember why dogs sniff butts

Why Do Dogs Sniff Butts? {And How It Might Save Their Life!}

This post was first written in 2015 as a freelance article.

Paris Permenter
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