The fur coat of a cat is made up of 68,250,000 (68.25 million) hair strands. The calculation is difficult to make accurately in my view. The calculation is 25,000 hair strands per square centimeter multiplied by 2,730 square centimeters total surface area of the cat. Each hair strand is made mostly of keratin. This is the same tough protein which makes up the skin’s outer layer which is called the epidermis and which is made of about 40 layers of dead, flattened cells.
The fur is therefore technically skin. Keratin is made of a fibrous structural protein called scleroproteins. α-Keratin is the type found in vertebrates – animals including cats who have vertebrae, interlocking bones forming the spine.
As fur is mostly made of protein its growth consumes a good proportion of the cat’s protein intake.
Each strand of hair is made of overlapping cuticle cells. A hair strand feels smooth if it is stroked along its length from skin to tip but rougher when the direction of travel is in the opposite direction.
This is because the overlapping cells ‘point’ towards the skin. The hair grows in cycles dependent upon the amount of light which means more growth and shedding in the warmer and longer days. Increased light stimulates a spring moult. Indoor cats shed all year round under mainly artificial light. Fur grows for a longer time in longhaired cats than in shorthairs.
All cats shed hair. Some people search for non-shedding cats. I am afraid they will be disappointed.
SOURCES: myself, Wikipedia, The Encyclopedia of the Cat by Dr Bruce Fogle.
SOME ARTICLES ON FUR: