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Old October 14th 04, 10:19 PM
Bobcat
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"dgk" wrote in message
...
I suppose I could check Google but I'm here so...
Someone at the cat show said that all tri-color (or tri-colour for

my
British friends) cats are female, or, if male, are sterile.
Seems odd but he was showing his purebreds so maybe he knew what he
was talking about. Does white count as a color?


Tortoiseshell and tricolor (calicoin America) cats are almost always
female. The very few male exceptions -1 in approx 200, I've heard -
are almost invariably sterile, and it's genetic. Here's a convoluted
description of why. Lotsa luck reading it!
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"The term tortoiseshell cat refers to a coloration pattern caused by a
combination of specific genetic traits. It is not a specific breed of
cat A cat breed is an infrasubspecific rank for the classification of
domestic cats. A cat is considered to be of a certain cat breed if it
is true breeding for the traits that define that breed. Only three
percent of owned cats belong to a cat breed, and an even smaller
percentage of those are suitable as show cats. A breeding certificate
proves that a cat belongs to a cat breed by showing the cat's pedigree
back to at least four generations. The whole concept of cat breeds is
a relatively new one. Two hundred years ago there was no such thing.
Today there are almost a hundred cat breeds. Varieties of domestic cat
can also be identified by characteristics other than breed. The
tortoiseshell markings appear in many different breeds.
The coats of tortoiseshell cats are a mixture of colours. It is often
reserved for cats with coats that look like black and orange patches,
while calico cat is typically two-thirds white, with orange and black
patches on their backs. Their coats may also combine red or ginger,
and occasionally silver or ginger tabby patterns. The size of the
patches can vary from a fine speckled pattern to large areas of
colour. Cats with a basic white colour and red and black patches are
known as tortoiseshell-and-white in Britain, or, in the United States,
calico.
Coat coloration in cats is complex. The genes involved include the
Orange gene, O, which in its dominant form, O, produces orange fur,
and in its recessive form, o, produces black fur.
For a cat to be calico, it must simultaneously express two genes, O
and o, which are located at the same location on the X chromosome A
sex-determination system is a biological system that determines the
development of sexual characteristics in an organism. Most common
sex-determination systems in animals involve a genetic mechanism based
on the chromosomes of that organism. However, other systems can
involve other variables such as temperature. The details of some
sex-determination systems are not yet fully understood. Occasionally a
male is born. These have Klinefelter's syndrome Klinefelter's syndrome
is a condition caused by a chromosomal abnormality in males
(specifically, a nondisjunction); sufferers have a pair of X sex
chromosomes instead of just one. The XXY chromosome arrangement is a
common genetic abnormality, occurring as frequently as 1 in 1,000 male
births, but the symptoms that may result from having the extra
chromosome are less common. Because of this extra chromosome,
individuals with the abnormality are usually referred to as "XXY
Males" rather than as "suffering from Klinefelter's syndrome and are
almost always sterile."
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http://encyclopedia.thefreedictionar...iseshell%20cat

Aren't you glad you asked? g