Why Do Dogs Have Whiskers Under Their Chin?

You’ve stared at your favorite pooch’s face for hours. You’ve nuzzled his nose. You’ve grabbed his jowls. During all of this attention to his face, you’ve probably noticed the little long hairs that look like eyebrows and the random long hairs that stick out of his muzzle. What about under his chin? Have you ever detected the sporadic long and prickly whiskers there? Your dog has whiskers, or vibrissae, scattered across his head. The word “vibrissae” comes from the Latin word “vibrio,” meaning “to vibrate.” That is exactly how your dog’s chin whiskers communicate to him -- through vibration.

Chin whiskers are longer, stiffer and three times the thickness of regular dog hairs. They sprout out of small mounds on the chin and other parts of a dog’s muzzle. These small mounds that look like beauty marks are filled with nerves and connectors. Multiple whiskers can grow out of one mound. The whiskers are deeply embedded in the mound inside a hair follicle that is packed with nerves and blood. This is what makes whiskers so sensitive and they will bleed profusely and painfully if forcibly pulled out.

Chin whiskers work with other whiskers on a dog's face to give him feedback about his surroundings. If your dog want to get a drink or a bite to eat in the middle of the night, his chin whiskers provide vital feedback about the distant to the bowl and how far down the water or food is within the bowl. Since he can’t see as well in the dark as he can in daylight, this tactile information is sometimes more important than actually seeing. His chin whiskers are so sensitive that changes in air currents tell him where walls, steps and other objects are. Dogs know where their face is even if they are chasing a rabbit down a dark hole or tunnel and can’t see at all.

Another function of the chin whiskers is a potential defense mechanism. The chin whiskers can pick up vibrations that your dog reads. If your dog perceives the information received through these vibrations as a threat, he can use this information against the predator in defense. Chin whiskers also provide him with feedback about the location and movement of an opponent in the event of combat. Certified dog behavior consultant Joyce Gamsby Kesling proposes the possibility of an aggressive reflexive behavior triggered by someone’s or something’s breath as it is blown in the face of the dog. In these cases, the dog brings his chin whiskers forward in a knee-jerk response when he is aggressively stimulated.

Like all hair follicles, chin whiskers are subject to disease. Pyoderma is one such disorder where a bacterial skin infection causes cuts filled with pus. Demodex mites can burrow into the hair follicle causing pus-filled sacs and loss of whiskers in a disease called demodectic mange. Plucking chin whiskers can cause infection because of the exposed nerve mound. Hair follicle dysplasia occurs when the chin whisker grows abnormally or in the wrong place. Should your dog exhibit any of these symptoms, take him to the veterinarian for diagnosis and treatment.