HOW IT ALL STARTED
It is hard to believe that all types of Kois came from the rather plain, black common carp (Cyprinus carpio), but it is true. Similar to other pets that have been selectively bred like cats and dogs, fish was as well.
The earliest written records of Koi, or Nishikigoi, (Japanese for "brocaded" carp) were first described in writing from a Chinese book written during the Western Chin Dynasty, around 265-316 A.D. At that time they were described as white, red, black and blue. (Quoted from Absolute Koi website)
Koi are believed to have been introduced to Japan with the invading Chinese and a first account of them being kept by an emperor in Japan, apparently dates Back to AD 200. (Quoted from Absolute Koi website)
From what our understanding is, the common carp was first transported from Eurasia to the Far East more than 2,000 years ago. It finally made it way to Japan approximately 1,000 years ago, where they were bred as food source. It is believe that through trading with China or Korea, that these common carps were introduced to Japan.
These Japanese farmers would keep these carps in mud ponds, but not in the rice paddies because the carps would be eating the rice plants. Due to the fact that these fish are kept in such a small gene pool, it is normal for mutations in the species to happen, in this case, it was the changes in color. These colored fish were prized by their owners and seen as treasure instead of a food source. From there the farmers started the trend of breeding them as a hobby. Now is it widely appreciated by everyone around the world.
KOI BREEDING BEGINS
Koi can live for decades. One famous scarlet Koi, named "Hanako" (c. 1751 - July 7, 1977) was owned by several individuals, the last of which was Dr. Komei Koshihara. Hanako was reportedly 226 years old upon her death. Her age was determined by removing one of her scales and examining it extensively in 1966. She is (to date) the longest-lived Koi fish ever recorded. (Wikipedia)
It is not definite on when did the first mutations in the farm Koi occurred, but the result was of a red carp called "Hookazuki" and from that carp it brought about the all white Koi. Through crossbreeding those two colored Kois they gave us the first red and white carp, the Kohaku. In other region of Japan like Niigata at about the same time there was also a different kind of Koi mutations happening as well. It was the development of the all black Koi, Magoi, resulting from mixing a brown/black and blue/black carp together. Also during the first group of mutation in Koi was the first true blue Koi, the Asagi (meaning light blue). Years later the Asagi Sanke was bred with a Doitsu Metallic Koi, giving us the first Shusui (autumn water).
The Bekko Koi breed was introduced during the third mutation of the Nishikigoi. The varieties consist of Shiro Bekko, Aka Bekko, and the Ki Bekko.
In 1915, a 15 years old Sanke Koi was presented to the public. A Sanke is a three colored Koi also called Taisho Sanshoku. This was considered the last development of the traditional Koi breeds.
As early as the 1900s Koi keeping became very popular. It became a well known symbol of luck and prosperity. It was not long before the Japanese introduced a new breed of carp. It had large shiny scales and it was imported from Germany. This new breed became known as Doitsu (Meaning "German"). The Crossing between the Doitsu and the Japanese carp resulted in scales varieties also later to be known as the Doitsu Nishikigoi. Not long after the introduction of these varieties the last piece of the genetic code was completed to develop the Ogon. Shortly after the end of the Taisho era (with the discovery of the Showa) the Showa Sanke was developed. It was not until 1946 that finally the Ogon (golden Koi) was produced. Today Ogon also means single colored Koi. Most Koi developed after these periods are considered modern breeds. Today, 13 colors and all of their varieties are recognized for Nishikigoi.
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