Sentence:  Attempts are now being made, by selection, to create a new breed of <WSD>yak</WSD> (the Datong <WSD>yak</WSD>) from such crosses. Hybridization of domestic <WSD>yak</WSD> with local cattle, at intermediate elevations, has been practiced for generations. The hybrids inherit some of the good characteristics from each species, but lack the adaptation of the <WSD>yak</WSD> to the harsh conditions at higher elevations. 
Meaning of the word marked with <WSD> tags:  An ox-like mammal native to the Himalayas, Mongolia, Burma, and Tibet with dark, long, and silky hair, a horse-like tail, and a full, bushy mane.