A whisker plot?

Illustration: Kevin Brockbank

Wilhelmina was a blue merle Sheltie who was only four years old when she lost most of her sight. Although she could still make out light and dark, her vision was probably the equivalent to seeing through several layers of tracing paper.

Her owner, Bruce, asked dog neuropsychologist Stanley Coren for advice on how to help her. “My recommendations included leaving items of furniture in their same places so that she could form a consistent “map” of her environment and using scents or textured materials such as throw rugs to mark areas,” recalls Coren in his book, How Dogs Think.  “Willie adapted well and would zoom around the house like a sighted dog most of the time, with only an occasional stumble or collision that reminded the family that she was blind.”

But then disaster struck. On returning home one day from the dog groomers, Willie ran up the steps to go into the house and collided with the door jamb. “As she made her way through the house she banged into a chair and table leg. Now, looking a bit distressed and confused, she began to slow down and move quite tentatively,” remembers Coren. “A bit later, when she went to drink some water, her head actually missed the bowl completely and she bumped her nose on the floor.”

Her owners were distraught and called Coren fearing that she had suffered some sudden mental deterioration.  In fact, it turned out that the dog groomer had cut off Willie’s whiskers, something that had never been done before, and it had robbed her of what Coren believes are an important sensory tool. As they grew back, Willie recovered her ability to navigate round her world to the considerable relief of her owners.

Although we call them whiskers, the proper name for them is “vibrissae” and they are nothing like the non-functional whiskers men sometimes grow on their faces -  or like any other kind of hair that grows on us.  Indeed, we should think of these thicker, stiffer hairs more as “feelers”  - as they are on cats, rats, mice and many other mammals, including seals and even whales.   They are rooted four times deeper than a normal hair, surrounded by erectile tissue and fed with many more nerve fibres and a much more substantial blood supply.  In fact, they are sometimes called “blood hairs” because they bleed when they are plucked out.

And plucked out they sometimes are (although more commonly, trimmed, clipped or shaved) by some dog groomers and owners as part of the grooming process or for preparing dogs for the show ring. According to some experts, we shouldn’t be doing it.

“Many dog fanciers are unaware of the importance of vibrissae to the dog,” says Stanley Coren. “Dogs of many different breeds routinely have their vibrissae cut off in preparation for the show ring. It is argued that this gives the dog’s head a 'cleaner' look.  Amputating vibrissae is both uncomfortable and stressful for dogs, and it reduces their ability to perceive their close surroundings fully."

Coren believes that the vibrissae serve as “an early warning device that something is near the face, protect the dog from colliding with walls and objects, and keep approaching objects from damaging the dog’s face and eyes.”

You can check this for yourself, says Coren, by tapping gently on the vibrissae of a dog. In many dogs, with each tap, the eye on the same side of the face will blink protectively and the dog will tend to turn its head away from the side tapped.

“Dogs have several sets of vibrissae,” explains biologist  and saluki breeder, Dr John Burchard. “The ‘whiskers’ on either side of the
 muzzle are familiar to everyone. They are called ‘mystacial’ vibrissae (from 
the same root as ‘moustache’). On closer examination you will also notice a
 system of seven ‘hair warts’ forming a sort of crown surrounding the head, 
giving the dog information about where it can safely stick its head, and where 
it can't. There is one tuft of vibrissae just above each eye, two 
on each cheek (one upper, one lower) and one under the middle of the chin. In a
 dog with a normal shaped head, those seven tufts of vibrissae form a roughly 
equal spaced circle all around the head, providing important information about
 the surroundings in a zone where the animal cannot see.”


That these special whiskers are of vital importance in some mammals is in no doubt.  A large part of the brain is dedicated to processing the nerve impulses from vibrissae. If vibrissal papillae are damaged in newborn mice, it results in abnormal brain development. Rats are fantastic swimmers – able to swim for up to 48hours - but in one experiment (Richter, 1957), rats that had their vibrissae removed before being put into water swam frantically for a minute or so before giving up and sinking to the bottom of the tank. An autopsy revealed that they hadn’t drowned; they had died of a cardiac arrest, apparently unable to cope without their whiskers. Likewise, it has been found that blindfolded cats can still find and neatly despatch their prey if their whiskers are intact – but not if they are removed. (Paul Leyhausen, Cat Behaviour, 1979)

“They are highly innervated (supplied with nerves), so if they touch something or if the wind blows on them, there will be feedback to the dog’s brain,” says Debra Eldredge, DVM, of Vernon, New York, author of the Dog Owner’s Home Veterinary Handbook (Wiley, John & Sons, Incorporated, 2007).

In his 1982 report “Whisker Trimming in Show Dogs” (download pdf here), Professor Thomas McGill, a psychologist and Newfoundland breeder, tells the story of a top-winning Vizlsa who sustained  facial injuries when hunting during his youth when he was also being shown (with his vibrissae removed), but not once after he retired from the show-ring and his whiskers were allowed to grow.  

McGill also reports how, according to one obedience trainer, removing vibrissae appeared to interfere with young gundogs’ ability to retrieve. “When the dumb-bell is thrown for them, they approach it, begin to pick it up and then drop it and return to the handler.” This was particularly likely to happen if the vibrissae were growing back after being cut for the showring - apparently caused by the discomfort of the vibrissal stubs hitting the dumbbell.

There are very similar anecdotal reports of horses sustaining facial and eye injuries after their vibrissae have been trimmed (again, done mostly for the show-ring where some exhibitors talk of their horse or dog losing marks for not having their whiskers removed).  Some owners claim their horses use their vibrissae to detect whether or not an electric fence is on.  One handler tells of a mare who refuses to eat for two days after her whiskers are shaved off; another of horses reacting almost like they have been shocked when the stubble of re-growing vibrissae bump into things.

The concern is such that the British Horse Society now advises that they should not be removed and in Germany the practice has been banned in horses on the basis that it is sensory deprivation.

On the other hand, many owners (of both horses and dogs) say that their animals don’t mind their vibrissae being removed – even plucked -  and insist that it makes absolutely no difference to them or their abilities.

“If I thought for a minute my dog's lives were in any way negatively 
impacted by whisker trimming, I wouldn't do it. I just don't see any 
evidence of an issue. I genuinely don't,” says Carolyn Horowitz, who breeds, shows and works her Manchester Terriers.

“We routinely do whiskers on our dogs, and they don't so much as twitch when you touch them or even when we shave them off.  My guys are perfectly functional hunting with or without whiskers.  I think the issue is pretty silly, frankly.

“I'm not suggesting everyone run out and clip off their dog's whiskers, rather there are much bigger fish to fry in the quest for canine welfare than worrying whether a couple of thousand dogs on the entire planet have their whiskers trimmed off when actively showing. “  

Carolyn’s view is widely echoed by showdog owners who choose to trim their dogs’ whiskers – and also by groomers who insist that it doesn’t harm the dogs in any way.  Supporting them is the fact that dogs do not yelp when they are removed (the nerve supply is just to their base; the hair itself contains no nerves) and many dogs do appear to function perfectly well without them.  Also, no one has done specific research on how important they are to the dog – it’s all assumption based on data in other animals and anecdote. 

“Vibrissal function is less highly developed in dogs than in several other 
mammalian groups and 
probably less than in wolves,” agrees Dr John Burchard. “But that doesn't mean they are non-functional.”

Just for a minute, close your eyes and imagine what it would be like to be stuck in a pitch black room with no arms and fingertips to help you find your way.  What would you use to help you navigate?  Your feet? Your shoulder? Or perhaps you’d dip your head and use your hair as a buffer? This is one of the roles vibrissae play for dogs and not just in the dark.

I asked the British Veterinary Association what it thought.  “The BVA has not had the opportunity to debate this issue in any detail and therefore does not have a formal policy,” replied BVA president Harvey Locke. “However, I can say that whiskers should not be trimmed, shaved or removed for cosmetic reasons and in cases where the muzzle is clipped for cleanliness every effort should be made to preserve the vibrissae. They are a sensory organ with innervation so it is reasonable to assume that their amputation causes discomfort.”

In the US, Thomas McGill campaigned so strongly on the issue that it has resulted in some breed standard changes. The AKC Newfoundland standard now reads: “Whiskers need not be trimmed” while the Vizsla standard reads: “Whiskers serve a functional purpose; their removal is permitted but not preferred.”

Breed standards here in the UK make no specific reference to the wisdom or otherwise of removing whiskers, but last December the Kennel Club did issue a statement saying that it did not believe any dog should have its whiskers removed for purely cosmetic reasons, and also expressing  concern that whisker removal was becoming more commonplace in clean-faced breeds. 

“As humans we are so accustomed to 
our own more limited sensory abilities that we tend to underestimate the sensory 
abilities of other species,” says John Burchard.

“I consider plucking vibrissae to be animal abuse. Clipping them is not quite so
 bad but I still find it disgusting. It is commonly done to Whippets in the show
ring - and a Whippet is surely one of the dogs with the very least need of any 
kind of trimming.”

Stanley Coren agrees: The vibrissae of dogs serve an important function and this becomes even more important as the dog ages and his eyesight dims. Removing the vibrissae simply to make the dog's face look cleaner I believe is unnecessary and harmful to the animal. Unfortunately, as you have mentioned, few dog groomers seem to be aware of this, and even worse, many judges in dog conformation shows still give preference to dogs who have had their vibrissae removed. I even had a dog judge tell me that I should have whiskers removed from my dog, adding the bizarre comment "You don't want your dog to look so hairy do you?"

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This article is adapted from the version that appears in the July 2011 issue of Dogs Today magazine.  Dogs Today is now available internationally for iPad and iPhone for the bargain price of 59p for the app, which includes one edition free.