I know my granfer (dairy farmer for about 50years) had an arrangement with 3 farms in the area... they'd all swap their bulls around every other year or so, to strengthen the herds. After several rotations, the bull would end up in the butchers across the road and we'd invariably end up having a large piece of him for Christmas dinner.

That's what REAL farming folk do... don't recall any of these shenannigans going on in the milking parlour.... too much bloody work to do!

LTS