Why Do Dogs Lick Each Other's Mouths?

Your canine buddies have the oddest behavior: They lick each other’s faces, plus they even lick the neighborhood dogs while you’re out on a walk. Dogs lick one another’s mouths for all kinds of reasons. It’s a perfectly acceptable behavior in the doggy world -- you have nothing to be concerned about.

Chester gobbles up everything in his bowl each morning, leaving a trail of crumbs all around his mouth. It’s no wonder Benny always licks Chester’s face completely clean. Benny kind of gets rewarded for licking Chester by getting a few miniscule bits of kibble. He’s learned that by waiting patiently for Chester to finish his entrée, he’ll get a little extra grub in his belly.

Mouth licking in the canine universe is much like shaking hands in the human world. You’ll see your pooch eyeball that dog on the other side of the park and slowly approach him. They’ll read each other’s body language -- watching for upright ears, relaxed and wagging tail and a muzzle straight up in the air. As long as Chester gets the go ahead, he’ll approach that strange dog and lick her snout as a way to say hello. Be thankful you have such a happy pup who gets along perfectly with just about any dog who crosses his path.

Canines are well known for their reliable sense of smell. At the top of their mouths, right next to the nasal cavity, dogs have a vomeronasal organ that helps them gather even more information about their surroundings. When Benny goes up and licks Chester’s snout after his evening walk, Benny is gathering information about where Chester went. When he licks, he inhales scents from Chester’s face that you can’t smell. He can tell where Chester ran off to and who he was with by breathing in and pulling those scents across the vomeronasal organ.

Your four-legged chum could just be a compulsive licker -- it’s in his genes. Licking other dogs right on their muzzle soothes him, makes him happy and just gives him something to do. Some breeds are more likely to be compulsive lickers than others, notes the ASPCA. Doberman pinschers, golden retrievers and Labrador retrievers, just to name a few, are probably going to be a little lick happy. Compulsive licking isn’t generally anything to worry about, just be wary about letting Chester approach foreign dogs. They might not like to be licked.