Why Do Dogs Sniff Butts?

Kate Barrington
by Kate Barrington
Don’t fall behind when interpreting your pooch’s behavior. Here’s why dogs sniff butts – it’s more than saying hello.

You don’t have to be a dog owner yourself to know what a dog’s first move will be when he encounters another dog – he will run right up to it and stick his nose under its tail. Butt sniffing is a behavior that every dog exhibits, not only around other dogs but sometimes with humans as well. The question is, do you know why he really does it?

What Can Dogs Learn by Sniffing Butts?

Whereas humans communicate using words and hand gestures, dogs rely on body language and scents for communication. In fact, your dog’s nose is about 10,000 to 100,000 times more powerful than your own nose and it can hold up to 225 million olfactory receptors. Your own nose, while it may be similar in size to your dog’s, has a much smaller olfactory membrane and it only contains 5 million olfactory receptors. When your dog smells something he takes in a great deal more information about the person, animal, or object than you would gather from taking a whiff with your puny human nose.

Related: 6 Bizarre Ways Our Dogs Talk to Us

As you may or may not be aware, all dogs have small glands on either side of their anus (called anal sacs, or anal glands) that produce certain chemicals. These chemicals are like a finger print in that they are completely unique to your dog. By catching a whiff of this chemical from another dog, your dog can learn a lot of information such as the dog’s sex, health, reproductive status, and even his diet. In many ways, sniffing butts for dogs is similar to shaking hands for humans – it is the customary way to greet someone and it can tell you a lot with just that simple form of interaction.

Should You Try to Stop Your Dog?

Sniffing butts is a natural behavior for dogs, but there is a time and a place for it. While it might be perfectly acceptable for your dog to do this when he meets another dog, your human houseguest might not appreciate your dog shoving his nose into their crotch. You shouldn’t try to stop your dog from sniffing another dog, but you can train him not to treat your human friends this way. It might help to ask your dog to sit and stay when new people come to the house, allowing them to approach your dog instead of the other way around. You may also want to give your guests a heads-up if your dog has a habit of crotch sniffing.

Related: New Study Fuels Anti Tail Docking and Ear Cropping Standards

In most cases, letting your dog sniff another dog is completely harmless but you should always keep an eye out when your dog is meeting new people or dogs. Some dogs simply do not get along well with other dogs so you want to be careful about letting your dog get too close. When you take your dog for a walk it is always a good idea to ask permission from the owner before letting your dog approach another dog and you should keep your dog under control when there are other dogs around. If you take your dog to the dog park there is an unspoken understanding that your dog is generally friendly around other dogs and you can assume that the same is true for the other dogs, though you should always supervise your dog closely, just in case.

Even though sniffing someone’s butt is probably not something you would do as a means of greeting them, it is a normal behavior for your dog and not one that you should discourage unless it becomes a serious problem. Just remember that sniffing a dog’s butt is how your dog learns important information and it is a harmless behavior.

Kate Barrington
Kate Barrington

Kate Barrington is the loving owner of two cats (Bagel and Munchkin) and a noisy herd of guinea pigs. Having grown up with golden retrievers, Kate has a great deal of experience with dogs but labels herself a lover of all pets. Having received a Bachelor's degree in English, Kate has combined her love for pets and her passion for writing to create her own freelance writing business, specializing in the pet niche.

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