Kitten

A kitten (also known as a kitty or kitty cat) is a juvenile cat. After being born, kittens are totally dependent on their mother for survival and they do not normally open their eyes until after seven to ten days. After about two weeks, kittens quickly develop and begin to explore the world outside the nest. After a further three to four weeks, they begin to eat solid food and grow adult teeth. Domestic kittens are highly social animals and enjoy human companionship.

The word "kitten" derives from the Middle English word kitoun, which in turn came from the Old French chitoun or cheton. Juvenile big cats are called "cubs" rather than kittens; either term may be used for the young of smaller wild felids, such as ocelots, caracals and lynx, but "kitten" is usually more common for these species.

A feline litter usually consists of two to five kittens born after a gestation lasting between 64 and 67 days, with an average length of 66 days. Kittens emerge in a sac called the amnion, which is bitten off and eaten by the mother cat.

For the first several weeks, kittens are unable to urinate or defecate without being stimulated by their mother. They are also unable to regulate their body temperature for the first three weeks, so kittens born in temperatures less than 27 °C (81 °F) can die from hypothermia if their mother does not keep them warm. The mother's milk is very important for the kittens' nutrition and proper growth. This milk transfers antibodies to the kittens, which helps protect them against infectious disease. Newborn kittens are unable to produce concentrated urine, and so have a very high requirement for fluids. Kittens open their eyes about seven to ten days after birth. At first, the retina is poorly developed and vision is poor. Kittens are not able to see as well as adult cats until about ten weeks after birth.

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