The Kiso or Kiso Horse ( ja, 木曽馬, kiso uma) is one of the eight indigenous

horse breeds This article is a list of horse and pony breeds with articles on Wikipedia, and also includes terms for types of horse that are not necessarily standardized breeds but are often labeled as breeds. While there is no scientifically accepted defin ...

of Japan. It is the only native horse breed from

Honshu , historically called , is the largest and most populous island of Japan. It is located south of Hokkaidō across the Tsugaru Strait, north of Shikoku across the Inland Sea, and northeast of Kyūshū across the Kanmon Straits. The island se ...

, the principal island of Japan. Like most other Japanese native breeds, it is critically endangered.

History

Japanese native horses are thought to derive from stock brought at several different times from various parts of the Asian mainland; the first such importations took place by the sixth century at the latest. Horses were used for farming – as pack-animals although not for draught power; until the advent of firearms in the later sixteenth century, they were much used for warfare. The horses were not large: remains of some 130 horses have been excavated from battlefields dating to the

Kamakura period The is a period of Japanese history that marks the governance by the Kamakura shogunate, officially established in 1192 in Kamakura by the first ''shōgun'' Minamoto no Yoritomo after the conclusion of the Genpei War, which saw the struggle bet ...

(1185–1333 AD); they ranged from in

withers The withers is the ridge between the shoulder blades of an animal, typically a quadruped. In many species, it is the tallest point of the body. In horses and dogs, it is the standard place to measure the animal's height. In contrast, cattle a ...

height. The Kiso breed originates from the

Kiso Valley The is a geographical area that centers on the valley of the upper portions of the Kiso River in the southwestern part of Nagano Prefecture in Japan. It is a v-shaped valley with length of approximately 60 km (36 mi) that follows the ri ...

and the Kiso Sanmyaku mountain range, in Nagano Prefecture, and the Higashimino region of Gifu Prefecture, in central

. During the Meiji era (1868–1912) it was severely affected by the breeding programme of the

Imperial Japanese Army The was the official ground-based armed force of the Empire of Japan from 1868 to 1945. It was controlled by the Imperial Japanese Army General Staff Office and the Ministry of the Army, both of which were nominally subordinate to the Emperor o ...

, which wanted taller horses and ordered that all stallions of the breed should be

gelded A gelding is a castrated male horse or other equine, such as a pony, donkey or a mule. Castration, as well as the elimination of hormonally driven behavior associated with a stallion, allows a male equine to be calmer and better-behaved, makin ...

, and that only imported stallions be used to cover Kiso mares. After the

Second World War World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposi ...

few

pure-bred Purebreds are "cultivated varieties" of an animal species achieved through the process of selective breeding. When the lineage of a purebred animal is recorded, that animal is said to be " pedigreed". Purebreds breed true-to-type which means the ...

Kiso horses remained. A single stallion, dedicated to a religious shrine, had escaped castration. His son Daisan-haruyama was born in 1951 and is the foundation stallion of the present-day breed. In 1899 there were 6823 Kiso horses. Between 1965 and 1976 breed numbers fell from 510 to 32. Registration of the breed began in that year, under the Kiso Pony Conservation Group, which was formed in 1969, and numbers have since slowly recovered. In 2013 the total population was estimated at 150. As a result of this population bottleneck, the

effective population size The effective population size (''N'e'') is a number that, in some simplified scenarios, corresponds to the number of breeding individuals in the population. More generally, ''N'e'' is the number of individuals that an idealised population w ...

– which has been calculated to be 45.8 – is much lower than the census population. Four distinct sub-populations within the Kiso breed were identified in 2012. The Kiso Uma no Sato, or "Kiso horse village", at Kaita Kogen below Mount Kiso Ontake, is a centre for the breeding and conservation of the Kiso breed.

Characteristics

The Kiso is a small horse, but mid-sized in relation to other Japanese native breeds. Research published in 2011 found an average height of , an average thoracic circumference ( girth) of and a

cannon bone Good conformation in the limbs leads to improved movement and decreased likelihood of injuries. Large differences in bone structure and size can be found in horses used for different activities, but correct conformation remains relatively simil ...

circumference of . There was little

sexual dimorphism Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most an ...

: while males were marginally larger than mares, the difference was not significant. The size of the breed has decreased since 1948; this may be due either to

inbreeding Inbreeding is the production of offspring from the mating or breeding of individuals or organisms that are closely related genetically. By analogy, the term is used in human reproduction, but more commonly refers to the genetic disorders and o ...

or to lessening influence of the foreign stallions used before the War. The distribution of coat colours in Kiso horses has changed substantially since 1953: in 2011, approximately 93% of those studied were bay or dark bay, and the remainder either chestnut or buckskin

dun A dun is an ancient or medieval fort. In Ireland and Britain it is mainly a kind of hillfort and also a kind of Atlantic roundhouse. Etymology The term comes from Irish ''dún'' or Scottish Gaelic ''dùn'' (meaning "fort"), and is cognat ...

; in 1953, bay and dark bay made up less than 60%, and there were also small numbers of black, grey and palomino horses. All registered stallions in 2011 were bay. About 66% of the horses studied had a dorsal stripe.

References

{{Horse breeds of Japan , state=expanded Japanese culture Horse breeds originating in Japan Horse breeds