I know this is strange, but hear me out...what about WATER BUFFALOS?!?!
They can work on the farm pulling plows and whatnot, plus be used for meat and daily production. I was watching a documentary the other day about these guys vs the normal cow- yes, cows produce more like per day, BUT the water buffalo's milk contains higher protein and butterfat content, thus a higher quality and yield for both cheese and milk in the long run. If you had both on your farm, the water buffalo could be the rare/expensive/unique stuff compared to normal milk and maybe it could give extra traits- smarter for 24 hrs after consumption or something....?! IDK, just a thought :))