Other livestock species

Yak

Origin and distribution: The domestic yak (Bos grunniens) is a type of long-haired and bushy-tailed cattle and belongs to the subfamily Bovinae of the family Bovidae. The yaks are distributed over a large area of the higher parts of the mountain system (3000 – 5000 m above sea level) of central Asia, especially the Tibetan plateau and surrounding mountains (Himalayas, Karakoram, Kunlun, Nan Shan) and the mountain mass which stretches from the Pamirs and the Tien Shan in the west to the Altai mountains, the Sayan mountains (where the yak meets the reindeer and camel), and to Mongolia and the lake Baykal area in the east (Bonnemaire, 1984). According to the same author, yaks are occasionally found below 2500 m in the south of their distribution (Himalayas) and below 1500 m in the north (Mogolia and Buryat Mongolia). Epstein (1976) cited by Bonnemaire (1984) noted that the majority of yaks are concentrated in China (especially in Quinghai), and in Tibet, but also in Sichuan, Xinjiang, Kansu, and Yunnuan. Yaks are also bred in the former U.S.S.R., and Nepal (especially in northern belts). Countries with smaller populations are Bhutan, Afghanstan, and India.

Physical characteristics: The domestic yak has been described by Bonnemaire (1984). Briefly, they have a fairly long body, short and compact leg with particularly developed forequarters (having fourteen or fifteen pairs of ribs instead of the thirteen of domestic cattle). They have a characteristic bushy tail with very long profuse soft silky hair, which looks like the tail of a horse. There is a lateral fringe of fairly long hair (20–60 cm) on the flank and the lower part of the body. The withers are high and prominent on account of elongated neural spines. Fully-grown males generally weigh 300–350 kg and height at the withers is about 1.5 m (range: 1.15–1.35); the females weigh 180–350 kg and measure about 1.10 m (range: 1.00–1.25) at withers. The short slender neck is without dewlap. The head is relatively heavy and bulky, with characteristic curved horns. The udder is small and is covered with hair.

Peculiarity: Yaks are highly adaptable to high altitudes, low atmospheric pressure and low oxygen content of air. They can also graze on short grass areas grazed by sheep. They are unfavourably affected by high air temperatures but show an outstanding adaptation to living at a high altitude in the open air all year round under a very cold and rather dry climate, with periods of very poor feed. The average annual temperature in yak rearing areas is –8°C with yak being able to withstand temperatures of –40°C in the winter months (Shijan and Weisheng 1997). These peculiar characteristics are because of their plentiful coat, ability to move easily across all types of country, ability to graze very close to the ground, thick skin, large thoracic cavity, respiratory exchange potential higher than in cattle (large alveolar area; larger, more numerous erythrocytes with higher haemoglobin content), ability to scoop out the snow for feeding during the winter, and less weight loss during winter compared to cattle and sheep on the same pastures (Bonnemaire 1984).

Breed status: The present population of yak is not known. This is because in many countries they are generally included among cattle statistical tables. According to the New China News agency in 1979, there were about 4.6 million Yaks in China. Though they are many, their number in Tibet, Nepal, and Afghanistan is not known. They are more than 500 000 in Mongolia, 90 000 in USSR, 52 000 in Buthan, 18 000 in India (Bonnemaire 1984).

According to Bonnemaire (1984) the yak has the same chromosome number as other Bos and Bison species, and karyotypes are similar. Therefore, they are readily being crossed with several other species of Bos and Bison, giving single hybrids as well as triple hybrids. In Nepal, for example, male yak in the mountains are crossed with female hill cattle to produce Chauri (female) and Zhopkyos (male). Chauries are good milk yielder and zhopkyos are sterile and good for transportation as pack animals. Chauries and zhopkyos can come down to lower elevation than yak. Based on the available information, Chauries and jhopkyos production (kind of hybridization) in Nepal is unique in the world.

The yak population is decreasing because farmers are migrating to lower altitude areas where the yak are not suited. The domestic yak has been introduced even into regions far away from its original area, with greater or less success (Bonnemaire 1976). In the former USSR, yaks have been successfully introduced from the Pamirs into the Caucasus in order to exploit pastures at higher elevations. Acclimatisation trials in France and Scotland with few animals were also successful. They were introduced into North America and Canada in order to improve the hardiness of their local Bison and cattle through crossbreeding.

Utility: Yaks are used for many purposes, giving milk, work (mostly as pack animal, but also for draught and riding), dung for fuel, fibres, leather, and meat, in surroundings where most of the other domestic species cannot thrive. They are also used for general crossbreeding with cattle. At a low cost for its maintenance, the domestic yak produces nearly as much milk as the local cattle: an average milk production of 600 kg per lactation (range 120 to more than 1000 kg) with half generally sucked by the calf. The milk of the yak has a higher concentration of various nutrients than that of cattle: 6.5 to 7.0 per cent of fat (golden coloured and with large fat globules), 5.3 per cent protein, 4.6 percent of lactose and 17.4% per cent of total dry matter. Due to religious taboos on their slaughter, yak meat is of minor importance throughout the Tibetan area, but it is of great value in other countries such as Mongolia and the former USSR.

If properly fed with milk by their dams, growing yaks weigh about 200-260 kg when they are 18 months. The hair, plucked or shorn in the spring (400-1400 g per animal), is used to make ropes, tents or felt. The leather has many uses: for thongs, shoes, bottles and even boats (in Tibet). For draught purposes, the yak is used mainly as a pack animal due to its uncommon agility through difficult mountainous ranges and also its ability to carry burdens of 50–80 kg.

Fig 1. Distribution of the yak in Asia

Source: Adopted from Bonnemaire (1984)

References

Bonnemaire J. 1984. Yak. In: Mason I.L. (ed), Evolution of domesticated animals. Longman, London, UK. pp. 39–45.

Bonnemaire J. 1976. Le yak domestique et son hybridation. Ethnozootechnie 15: 46-77.

Shijan G. and Weisheng C. 1997. The situation of yak in China. In: Miller D.G., Craig S.R. and Rana G.M. (eds), Proceedings of a workshop on conservation and management of yak genetic diversity held at ICIMOD, Kathmandu, Nepal, 29–31 October 1996. ICIMOD (International Centre for Integrated Mountain Development), Kathmandu, Nepal. pp. 25–28.

Related Literature

Bonnemaire J. and Jest C. 1976. Le yak; son rôle dans la vie matérielle et culturelle des éleveurs d'Asie Centrale. Société d'Ethonozootechnie. Ethnozootechnie, 15. Paris, France. 170 pp.

Bonnemaire J. and Jest C. 1993. L'élevage du yak en Asie Centrale. Bulletin d'information sur les ressources génétiques animales, 12. FAO (Food and Agricultural Organization of the United Nations), Rome, Italy. pp. 49–61.

Jianlin H., Richard C., Hanotte O., McVeigh C. and Rege J.E.O. (eds). 2002. Yak production in central Asian highlands. Proceedings of the third international congress on yak held in Lhasa, P.R. China, 4–9 September 2000. ILRI (International Livestock Research Institute), Nairobi, Kenya. 572 pp.

Related websites

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