Cat whiskers are made of keratin. It’s the same material which makes calluses, hooves, claws, horns, feathers, nails, hair and scales. So it is the same substance that makes a cat’s fur coat only the individual hair strands of cat whiskers are much thicker and their roots are three times deeper than standard cat hair.
Whiskers are highly mobile and very sensitive. They can detect anything that displaces them by a distance which is 2,000 times less than the width of a human hair as the base of each whisker is connected to a nerve complex. Whiskers also are able to provide a guide to a cat as whether they can get through a gap. The distance between the extreme ends of whiskers is the smallest gap that the cat can pass through. They are sensitive enough to detect air currents around objects which allows cats to detect these objects despite being visually invisible to a cat. In this sense they provide a form of eyesight in much the same way that the cat’s sense of smell helps a cat to recognise objects at close range by their scent.
A whisker’s follicle is about three times deeper than for a normal hair strand. A blood filled capsule called the “sinus” is on either side of the hair shaft and it “acts like hydraulic fluid and amplifies the signal sent to the web of sensory nerves around it.”
We know what keratin feels and looks like because we simply have to look at our nails. It’s a pretty hard substance, insoluble in water and to organic solvents such as alcohols, eg methanol.
Keratin cannot be digested by cats which is why when they groom themselves and ingest their fur they develop hairballs which are regurgitated (vomited).
The horns of the rhinoceros are made of keratin which tells us how strong the substance can be. It also tells us how bizarre it is that within traditional Chinese medicine it is believed that keratin has medicinal properties. It is believed that it can treat a very wide range of ailments and illnesses including fever, arthritis, gout, headaches, hallucinations, high blood pressure, typhoid, snake bites, food poisoning and even possession by spirits. There is no scientific evidence that keratin is effective in any of these treatments, therefore it is based on superstition.
Keratin is described as one of a “family of fibrous structural proteins known as scleroproteins” (Wikipedia). The Sphynx cat, a more or less hairless cat, has ragged short whiskers or no whiskers. This must affect the functioning of the cat as whiskers serve a useful purpose. That is why Germany describes the creation of these cat breeds as “torture breeding“. The Persian is another breed in this category.