Dzo

{{Short description|Hybrid between the yak and domestic cattle}}

{{Redirect|zho|the ISO 639-3 language code|Chinese language}}

{{For|DZO, the jargon term used in physics and chemistry|Depleted zinc oxide}}

{{Hybridbox

| name = Dzo

| image = Zokyo loaded with bags.jpg

| image_caption = A dzo acting as a pack animal en route to Mount Everest

| status = DOM

| genus = Bos

| species1 = grunniens

| link1 = Yak

| species2 = primigenius taurus

| link2 = Aurochs}}

A dzo ({{langx|bo|མཛོ་|mdzo}}) 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 {{transliteration|bo|dzomo}} or {{transliteration|bo|zhom}}. In Mongolian, it is called a {{transliteration|mn|khainag}} (хайнаг). There is also the English portmanteau term of yattle—a combination of the words yak and cattle,{{cite news |url=https://www.washingtonpost.com/wp-dyn/content/article/2007/08/10/AR2007081002119.html |title=Yattle What? |last=Mummolo |first=Jonathan |date=August 11, 2007 |newspaper=The Washington Post |access-date=January 3, 2017 |quote=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.}} as well as yakow{{cite book |author=National Research Council |author-link=National Research Council (United States) |date=1983 |title=Little-Known Asian Animals With a Promising Economic Future |url=https://www.nap.edu/catalog/19514/little-known-asian-animals-with-a-promising-economic-future |location=Washington, D.C. |publisher=The National Academies Press |page=34 |doi= 10.17226/19514 |isbn=978-0-309-32715-2 }}{{cite book |last=Mason |first=Ian |editor-last=Porter |editor-first=Valerie |date=March 2002 |title=Mason's World Dictionary of Livestock Breeds, Types and Varieties |url=http://www.cabi.org/bookshop/book/9780851994307 |location=West Sussex |publisher=CABI |page=122 |isbn=085199430X |access-date=2017-01-03 |archive-date=2017-12-23 |archive-url=https://web.archive.org/web/20171223215801/https://www.cabi.org/bookshop/book/9780851994307 |url-status=dead }}—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.{{cite book|author1=David B. Madsen|author2=Fa-Hu Chen|authorlink2=Chen Fahu|author3=Xing Gao|title=Late Quaternary Climate Change and Human Adaptation in Arid China|url=https://books.google.com/books?id=Ar8gTSpyK8sC|date=3 July 2007|publisher=Elsevier|isbn=978-0-444-52962-6|page=207}} In Mongolia and Tibet, khainags are thought to be more productive than cattle or yaks in terms of both milk and meat production.{{Cite web |url=http://www.fao.org/AG/AGAInfo/programmes/en/genetics/documents/Interlaken/countryreports/Mongolia.pdf |title=Bataagiin Bynie: Mongolia: The Country Refort (sic!) On Animal Genetic Resources, Ulaanbaatar 2002, p. 11 |access-date=2008-04-28 |archive-date=2015-09-24 |archive-url=https://web.archive.org/web/20150924011424/http://www.fao.org/AG/AGAInfo/programmes/en/genetics/documents/Interlaken/countryreports/Mongolia.pdf |url-status=dead }}{{cite book |last=Tsering |first=Diki |title=Dalai Lama, My Son |year=2002 |publisher=Penguin Books |isbn=0-7865-2260-7}}

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 {{transliteration|mn|khainag}} crossed with either a domestic bull or yak bull is called {{transliteration|mn|ortoom}} (ортоом, three-quarter-bred) and an {{transliteration|mn|ortoom}} crossed with a domestic bull or yak bull results in a {{transliteration|mn|usan güzee}} (усан гүзээ, one-eighth-bred).Takase Hisabumi, Kh. Tumennasan et al., [http://ci.nii.ac.jp/naid/110004313817/en "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.

Dzos inherit two distinct protein types, one from each parent, leading to alterations in their mitochondrial structure and function.Long, L., Zhu, Y., Li, Z., Zhang, H., Liu, L., & Bai, J. (2020). Differential expression of skeletal muscle mitochondrial proteins in yak, dzo, and cattle: a proteomics-based study. The Journal of veterinary medical science, 82(8), 1178–1186. https://doi.org/10.1292/jvms.19-0218 Consequently, this adaptation significantly enhances the dzo's capacity to thrive at higher altitudes compared to either parent.