|MOTHER SIAMESE AND HER|
The pointed pattern is a form of partial albinism, resulting from a mutation in tyrosinase, an enzyme involved in melanin production. The mutated enzyme is heat-sensitive; it fails to work at normal body temperatures, but becomes active in cooler areas of the skin. This results in dark colouration in the coolest parts of the cat's body, including the extremities and the face, which is cooled by the passage of air through the sinuses. All Siamese kittens, although pure cream or white at birth, develop visible points in the first few months of life in colder parts of their body. By the time a kitten is four weeks old, the points should be clearly distinguishable enough to recognise which colour they are. Siamese cats tend to darken with age, and generally, adult Siamese living in warm climates have lighter coats than those in cool climates. Originally the vast majority of Siamese hadseal (extremely dark brown, almost black) points, but occasionally Siamese were born with blue (a cool grey) points, genetically a dilution of seal point; chocolate (lighter brown) points, a genetic variation of seal point; or lilac (pale warm gray) points, genetically a diluted chocolate. These colours were at first considered "inferior" seal points, and were not qualified for showing or breeding. All of these shades were eventually accepted by the breed associations, and became more common through breeding programmes specifically aimed at producing these colours. Later, outcrosses with other breeds developed Siamese-mix cats with points in other cat colours and patterns including Red and Cream point, lynx (tabby) point, and tortoise-shell ("tortie") point.Siamese are usually very affectionate and intelligent cats, renowned for their social nature. Many enjoy being with people and are sometimes described as "extroverts". Often they bond strongly to a single person. Some Siamese are extremely vocal, with a loud, low-pitched voice – known as "Meezer", from which they get one of their nicknames – that has been compared to the cries of a human baby, and persistent in demanding attention. These cats are typically active and playful, even as adults, and are often described as more dog-like in behavior than other cats.
In the United Kingdom, all pointed Siamese-style cats are considered part of the Siamese breed. In the United States, the major cat registry, the Cat Fanciers' Association, considers only the four original colourations as Siamese: seal point, blue point, chocolate point, and lilac point. Oriental cats with colourpoints in colours or patterns aside from these four are considered Colorpoint Shorthairs in the American cat fancy.
They are sometimes less active at night than most cats, possibly because their blue eyes lack atapetum lucidum, a structure which amplifies dim light in the eyes of other cats. The mutation in the tyrosinase also results in abnormal neurological connections between the eye and the brain. Unlike many other blue-eyed white cats, Siamese cats do not have reduced hearing ability.
BREEDS DERIVED FROM THE SIAMESE
- Balinese – a longhaired Siamese. In the largest US registry, the Cat Fanciers Association (CFA), limited to the four traditional Siamese coat colours of seal point, blue point (a dilute of seal point), chocolate point, and lilac point (a dilute of chocolate point). Other registries in the US and worldwide recognise a greater diversity of colours.
- Burmese is a breed of domesticated cats descended from a specific cat, Wong Mau, who was found in Burma in 1930 by Dr. Joseph Cheesman Thompson. She was brought to San Francisco, California, where she was bred with Siamese. While technically not derived from Siamese, the breed was considered a form of Siamese for many years, leading to crossbreeding.
- Colorpoint Shorthair – a Siamese-type cat registered in CFA with pointed coat colours aside from the traditional CFA Siamese coat colours; originally developed by crosses with other shorthair cats. Considered part of the Siamese breed in all other cat associations, but considered a separate breed in CFA. Variations can include Lynx Points and Tortie Points.
- Himalayan - Longhaired breed originally derived from crosses of Persians to Siamese and pointed domestic longhair cats in order to introduce the point markings and the colours chocolate and lilac. After these initial crosses were used to introduce the colours, further breed development was performed by crossing these cats only to the Persian breed. In Europe, they are referred to as colourpoint Persians. In CFA, they are a colour division of the Persian breed.
- Javanese – a longhaired version of the Colorpoint Shorthair in CFA. In Europe, it is an obsolete term for the longhaired version of the Oriental Shorthair.
- Ocicat – a spotted cat originally produced by a cross between Siamese and Abyssinian.
- Oriental Shorthair – a Siamese-style cat in non-pointed coat patterns and colours, including solid, tabby, silver/smoke, and tortoise-shell.
- Oriental Longhair – a longhaired version of the Oriental Shorthair.
- Snowshoe – a cream and white breed with blue eyes and some points that was produced through the cross-breeding of the Siamese and bi-coloured American Shorthair in the 1960s.
- Thai Cat – also called the Wichian Mat or Old Style Siamese, the original type of Siamese imported from Thailand in the 19th century and still bred in Thailand today; and throughout the first half of the 20th century, the only type of Siamese bred in the West.
- Tonkinese – originally a cross between a Siamese cat and a Burmese. Tonkinese x Tonkinese matings can produce kittens with Burmese "sepia" pattern, Siamese "pointed" pattern, or a Tonkinese "mink" pattern which is something in between the two, with less pattern contrast than the Siamese but greater than the Burmese, and with aqua eyes.
- SOME BREEDS OF SIAMESE.
- lilac point Siamese
- seal point Siamese
- modern seal lynx point Siamese