The Kai Ken (甲斐犬, Kai-ken, Kai-inu[1], also called the Tora InuorTiger Dog) is a breedofdog native to the Kai region, Yamanashi Prefecture, Japan,[2] where it is a national monument. It is a rare dog even in its native land and is one of the six native Japanese dog breeds protected by the Nihon Ken Hozonkai.[3]
The Kai Ken is a medium-sized dog with a wedge shaped head and prick ears. Males are typically 18 to 22 inches at the shoulder, while the females are slightly smaller, 17 to 20 inches at the shoulder. The tail may be curled over the back, or carried in a sickle position. Limbs should be strong and hocks should be well developed reflecting the dogs’ history of mountain life. The coat is of harsh texture, medium length, and comes in various shades of brindle ("tiger" stripes). There are three main recognized shades of brindle: the Aka-tora (red), Chu-tora (middle), and Kuro-tora (black).[4] Puppies are born a solid color, and their brindle markings develop as they age, sometimes taking as long as five years before fully showing.
The Kai Ken is intelligent, agile, alert and brave. They are natural hunters and make good watch dogs, being reserved with strangers but loyal to their families. They are friendly, often good with children and are not usually aggressive towards other dogs. Many love to swim, and have been known to cross rivers and climb trees while chasing their prey.[5]
The Kai Ken was split off from the Nihon Ken (Japanese Dog) landrace during the creation of the Nihon Ken Hozonkai (NIPPO) and named after Kai ProvinceinYamanashi Prefecture where the breed is said to have originated.
Being an agile and effortless climber, the Kai Ken was used to hunt in steep mountainous terrain in Yamanashi where's its primary quarry was the Japanese serow (Kamoshika), deer, wild boar, and occasionally bear.
After the creation of NIPPO in 1928, the Kai Ken was designated a national monument in Japan in 1933. In 1931 the Kai Ken AigokaiArchived 2017-04-05 at the Wayback Machine (KKA) was formed and became the primary Preservation Society for the breed in Japan and still is today.
Many Kai Kens play important roles in the Yoshihiro Takahashi's series Ginga: Nagareboshi Gin and its sequel, Ginga Densetsu Weed, including the brothers Kurotora, Chūtora, and Akatora. In the sequel, Ginga Densetsu Weed, Kurotora's son, Kagetora, stars as an important character, with his less prominently featured brothers, Harutora and Nobutora, and cousins Dodo, Buru, Shōji, and Shigure.
Rover, a large dog monster who becomes the main character's pet later in the series, in One-Punch Man is based on a Kai Ken.
The mascot of Yamanashi Prefecture in Central Japan, Takeda Hishimaru (武田菱丸), is a Kai Ken samurai based on the historical figure of Takeda Shingen.[6]
