The Vibrissae: Why Horses Need Whiskers
Have you ever presented something to your horse that is slightly upsetting to him? A slight stiffness appears through the body, eyes alert, the ears perk forward and the nostrils flare, then after a few moments he puts his muzzle to the object?
“He’s just sniffing it.” Actually, it’s pretty likely the horse smelt the object from 10 feet away!
What he was actually doing was making contact with the object using the long white whiskers that protrude from the muzzle; these are called vibrissae.
Vibrissae are long, wire like tactile hairs that are found around the muzzle and eyes, but differ from that of other hairs on the body of a horse because they are a sensory organ. They have their own distinct nerve and blood supply. When a horse feels comfortable enough to investigate an object close up, he will make contact using these, which will in turn transmit information to the somatosensory cortex, the sensory section of the brain for ‘touch’, which has an area dedicated to these external sensors.
Now we know what they are do, why are they important?
In each animals genetic make-up, natural selection will not carry forward traits that do not serve a purpose, and will slowly phase these out. Every animal today has traits that it has carried over to benefit in some way. Vibrissae are no different.
Helping to protect the horse from the external environment, vibrissae guard some of the most vital parts of the horses body against damage, protecting the eyes and the muzzle area. We are all aware of the blind spots of a horse, but here I will refer to that at the end of the muzzle. These hairs play an important part of sensing where the eyes can’t see, the depth between a surface and the lips, the texture, and the temperature. Information valuable for the horse to determine what is safe or what could harm them. They are essentially the hands of a horse.
This all spells out that the vibrissae serve a pretty important role to the horse, unfortunately by some they are deemed unsightly, ugly and untidy, and are therefore clipped or cut off, generally for showing purposes. However, regulations are starting to come in to place around the world, in counties such as Germany, banning the clipping of these hairs and other medieval regulations. I very much hope the rest of the world decides to follow suit.