Dzo Dzo 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),
Animal Defenders International against the use of animals in circuses. ADI, through country-specific investigations, has contributed to the passing of animal rights laws, with Bolivia passing a law to ban both wild and domestic animal acts in all circuses; and similar legislation under consideration in Colombia and Peru. In the UK, ADI is lobbying the Department for the Environment, Food and Rural Affairs to introduce a ban on the use of “certain non-domesticated animals” in traveling circuses in line with DEFRA's 2006 promise to introduce an Act. ADI’s investigation into the use of animals in circuses in the UK and Europe in 1998,