Editing Kitten (section)

==Development==
[[File:1 dia de vida.jpg|thumb|A newborn [[Norwegian Forest cat|Norwegian Forest]] kitten]]

A feline [[Litter (animal)|litter]] usually consists of two to five kittens,{{sfn|Tsutsui|Stabenfeldt|1993|p=1699}} but litters with one to more than ten are known.<ref>[https://www.petcha.com/many-kittens-litter/ "How Many Kittens Are in a Litter? — Chewy"]. ''petcha.com''. 3 May 2016. Retrieved on 20 September 2018.</ref> Kittens are typically born after a [[gestation]] lasting between 64 and 67 days, with an average length of 66 days.{{sfn|Tsutsui|Stabenfeldt|1993|p=1699}} When they are born, kittens emerge in a sac called the [[amnion]], which is bitten off and eaten by the mother cat.{{sfn|Vandivert|1975|p=53}}

For the first several weeks, kittens cannot [[urinate]] or [[defecate]] without being stimulated by their mother.{{sfn|Pet Education 2011}} They also cannot regulate their body temperature for the first three weeks, so kittens born in temperatures less than {{convert|27|C|F}} can die from [[hypothermia]] if their mother does not keep them warm.{{sfn|International Cat Care 2015}} The mother's milk is very important for the kittens' nutrition and proper growth. This milk transfers [[antibody|antibodies]] to the kittens, which helps protect them against [[Infectious Disease|infectious diseases]].{{sfn|Casal|Jezyk|Giger|1996|p=1653}} As mentioned above, they cannot urinate, so they have a very high requirement for fluids.{{sfn|Sturgess|Hurley|2005|p=243}} Kittens open their eyes about seven to ten days after birth. At first, the [[retina]] is poorly developed and vision is poor. Kittens cannot see as well as adult cats until about ten weeks after birth.{{sfn|Tootle|Friedlander|1989|p=1325}}

Kittens develop very quickly from about two weeks of age until their seventh week. Their coordination and strength improve, and they [[play (activity)|play]]-fight with their litter-mates and begin to explore the world outside the nest or den. They learn to wash themselves and others as well as play hunting and stalking games, showing their inborn ability as predators. These innate skills are developed by the kittens' mother or other adult cats, who bring live prey to the nest. Later, the mother demonstrates hunting techniques for the kittens to emulate.{{sfn|Poirier|Hussey|1982|pp=133–148}} As they reach three to four weeks old, the kittens are gradually [[weaning|weaned]] and begin to eat solid food, with weaning usually complete by six to eight weeks.{{sfn|Sturgess|Hurley|2005|p=244}} Kittens generally begin to lose their [[deciduous teeth|baby teeth]] around three months of age, and they have a complete set of adult teeth by nine months.{{sfn|Veterinary Medicine 2013}} Kittens live primarily on solid food after weaning, but usually continue to suckle from time to time until separated from their mothers. Some mother cats will scatter their kittens as early as three months of age, while others continue to look after them until they approach [[sexual maturity]].{{sfn|Bönisch|1996|pp=23–24}}

The sex of kittens is usually easy to determine at birth. By six to eight weeks this becomes harder because of the growth of fur in the genital region. The male's [[urinary meatus|urethral opening]] is round, whereas the female's urethral opening is a slit. Another marked difference is the distance between [[anus]] and urethral opening, which is greater in males than in females.{{sfn|Walls|1991|p=22}}

Kittens are highly social animals and spend most of their waking hours interacting with available animals and playing on their own. Play with other kittens peaks in the third or fourth month after birth, with more solitary hunting and stalking play peaking later, at about five months.{{sfn|Crowell-Davis|2005|p=18}}

Kittens are vulnerable because they like to find dark places to hide, sometimes with fatal results if they are not watched carefully. Cats have a habit of seeking refuge under or inside cars or on top of car tires during stormy or cold weather. This often leads to broken bones, burns, heat stroke, damaged internal organs or death.<ref>Daphne Sashin, [http://pets.webmd.com/cats/features/risky-hiding-places-for-cats Five Risky Hiding Places For Cats]. WebMD, September 14, 2010.</ref>

Domestic kittens are commonly sent to new homes at six to eight weeks of age, but it has been suggested that being with their mother and litter-mates from six to twelve weeks is important for a kitten's social and behavioural development.{{sfn|Crowell-Davis|2005|p=18}} Usually, breeders and foster/rescue homes will not sell or adopt out a kitten that is younger than twelve weeks. In many jurisdictions, it is illegal to give away kittens younger than eight weeks of age.{{sfn|Sunquist|Sunquist|2014|p=111}} Kittens generally reach sexual maturity at around seven months old. A cat reaches full "adulthood" around one year of age.{{sfn|Santa Maria Times 2013}}