|A dzo acting as a pack animal en route to Mount Everest|
A dzo (Tibetan མཛོ་ mdzo) (also spelled zo, zho and dzho) is a hybrid between the yak and domestic cattle. The word dzo technically refers to a male hybrid, while a female is known as a dzomo or zhom. In Mongolian it is called khainag (хайнаг). There is also the English language portmanteau term of yattle, a combination of the words yak and cattle, as well as yakow, a combination of the words yak and cow.
Dzomo are fertile (or, fecund) while dzo are sterile. As they are a product of the hybrid genetic phenomenon of heterosis (hybrid vigor), they are larger and stronger than yak or cattle from the region. In Mongolia and Tibet, khainags are thought to be more productive than cattle or yaks in terms of both milk and meat production.
Dzomo can be back crossed. As a result, many supposedly pure yak or pure cattle probably carry each other's genetic material. In Mongolia, the result of a khainag crossed with either a domestic bull or yak bull is called ortoom (ортоом, three-quarter-bred) and an ortoom crossed with a domestic bull or yak bull results in a usan güzee (усан гүзээ, one-eighth-bred).
- Mummolo, Jonathan (August 11, 2007). "Yattle What?". The Washington Post. Retrieved January 3, 2017.
Mentzer, who grew up farming in Loudoun County, and his partner, Jim Dumbrell, a retired British oil and gas pipeline consultant, are breeding yattle -- a cross between cows and yaks.
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- David B. Madsen; Fa-Hu Chen; Xing Gao (3 July 2007). Late Quaternary Climate Change and Human Adaptation in Arid China. Elsevier. p. 207. ISBN 978-0-444-52962-6. CS1 maint: discouraged parameter (link)
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- Tsering, Diki (2002). Dalai Lama, My Son. Penguin Books. ISBN 0-7865-2260-7.
- Takase Hisabumi, Kh. Tumennasan et al., "Fertility Investigation in F1 Hybrid and Backcross Progeny of Cattle (Bos taurus) and Yak (Bos gruniens) in Mongolia: II. Little variation in gene products studied in male sterile and fertile animals", in: Niigata journal of health and welfare Vol. 2, No. 1, pp. 42–52.