The result of three mutationsIf bonsai proved that the Japanese people can handle the art of "dwarfism", with Onagadori cocks they show how they can deal with gigantism, too.
Onagadori ("Honourable Fowl" in Japanese) is a breed of domestic chicken and the cocks can have a tail reaching 10 m! This is an unchallengeable record amongst birds and perhaps some extinct huge sauropod dinosaurs could have had tails longer than 10 m!
The onagadori cocks can be colored in Black-breasted Red, Black-breasted Silver, Goishi (a pale Black-breasted Golden) and White. The leg color is willow in the Black-breasted variations and yellow in the Whites; blue legs are not accepted.
They grow in special cages in which the feathers of their tails are rolled up like a curl and suspended on the walls for protection. At about ten years of life the cocks attain this impressive tail length.
The onagadori cocks are the result of a mutation in "nm" (non-molting) genes that causes the extravagantly long growth of the tail feathers, but they also carry the "gt" and "sg" genes for rapid growth in tail feathers. Due to "nm" mutation, their tail feathers never molt, if kept in the best of conditions with high levels of animal husbandry, growing for the life of the roosters.
A portion of the tail does partially molt its sickle feathers annually and the body feathers may molt only every second or third year. The onagadori hens molt normally.
Till now, they have not been found in other countries. In Japan these cocks are protected. The record was reached by an Onagadori cock with a 11.3 m (38 ft) long tail.
The mutation that produced the Onagadori could have emerged on the breed Shokoku in the middle of the Edo Period (1600--1868). The Prince Yamanouchi in the Kochi Prefecture on the southern peninsula of Shikoku had the helmets and spears of his soldiers adorned with long rooster feathers for special occasions. The serfs who kept Onagadori chickens and delivered the long feathers were exempt from taxes. In about 1655, a steady selection for longer feathers was made.
During the Taisho Period (1912 - 1926), Onagadori tail feathers had already reached lengths over 6 m (20 ft).
The Onagadori cocks differ from the Phoenix breed, also originated in Japan and with long tail feathers, but no so long.