The beef industry may never be the same again, as scientists go, not “back to the future,” but back to the past. Or, once they realise the political ramifications, they may forget the whole idea.
The aurochs – said in this article to be as big as an elephant (wrong, they were big, but not that big) http://www.newser.com/story/236611/cows-as-big-as-elephants-may-soon-roam-europe.html, roamed Europe for 250,000 years, until being hunted to extinction in 1627.
Now, not exactly through genetic engineering, but selective breeding, geneticists believe that they can produce large cattle very close to the aurochs. These new “supercows” have already been released in Romania, Spain, Portugal, the Czech Republic and Croatia, and are apparently doing just fine. Even wolves are not much of a problem, as the animals are so big and strong, they just mince them.
However, be aware that the Nazis revered these beasts, as part of their Germanic/Aryan bad, bad, more bad mythology (http://www.independent.co.uk/news/science/nazi-super-cows-extinct-auroch-bring-back-aryan-myths-17th-century-adolf-hitler-ecosystem-preserve-a7518766.html), so humanity better not go there even if it could generate a billion dollar industry, and lots of juicy profits and steaks.