Deuteronomy 21:3
3 And the elders of the city that is nearest to the slain man shall take a heifer zthat has never been worked and that has not pulled in a yoke.
1 Samuel 6:7
7 Now then, take and prepare la new cart and two milk cows mon which there has never come a yoke, and yoke the cows to the cart, but take their calves home, away from them.