What is the cat tail for?
Approximately 10% of the bones in the cat's body are found in the tail. These bones are known as "caudal vertebrae". There's no set number of bones in the cat's tail, but an average number is between 20 and 23. This depends on the breed of cat and the length of the tail.
Some breeds of cat are known for their shortened tail or even complete absence of a tail. The Manx cat is probably the most famous cat to come to mind. It can be a "rumpy" with no tail, "rumpy riser", with some vertebrae, a "stumpy" with a longer but deformed tail and a "longie", the tail is longer still but still shorter than the average cat's tail. The Japanese Bobtail and American Bobtail are two other breeds of domestic cat with shortened tails.
The cat's tail is an extension of the spine and is used to help him balance and as an aid to communication.
The tail is an important tool to help keep kitty balanced when he walks along a fence. The tail is used as a counterweight, if he looks left, the tail will move in the opposite direction.
The tail can tell us (and other animals) a lot about the cat's current mood.
Tail swishing violently from side to side - Angry cat, possibly about to attack.
Tail held to one side - Sexual invitation from a female cat in heat.
Tail lowered and fluffed out - The cat is fearful.
Tail lowered and tucked between the hind legs - A submissive and frightened cat.
Tail held straight up and fully bristled - The cat is aggressive.
Tail raised and softly curved - Friendly cat greeting you.
Tail held still, tip twitching - Mild irritation.
Tail lowered and curved upwards - Relaxed cat.
Some cats have a habit of sucking their tail. This is thought to be a throwback to kittenhood when he would suckle from his mother, and not dissimilar to thumb sucking in humans. It is generally harmless unless done excessively, and then there may be some damage.
Some cats, especially Siamese and Burmese can be born with a kink in their tail. It's harmless in itself and causes the cat no pain or discomfort, it is a disqualifying fault on the show bench, though. Purebred cats born with kinked tails are usually sold as "pets", and not used to breed or exhibit.
It is said that the reason a Siamese cat's tail is kinked is that a Princess of the Royal House of Siam would place her rings on the tail of the Siamese while she bathed. Some say the cat fell asleep and the rings fell off, so she tied the tail in a knot in the future. Others say the cat itself kinked his tail to stop the rings falling off. Either way, it's a lovely story of how the Siamese came to have a kinked tail. The reality is it's a genetic trait passed on from the parents.
Injuries and diseases of the cat tail:
The tail can sustain injuries, the most common is a broken tail.
Abscess is another injury that can occur on the cat and is usually caused by a cat bite.