Not really Hucow focused, but have you tried Free Cities? (
https://www.reddit.com/r/freecitiesgame/)
It's a slave management game first and foremost. Relatively deep for new players too, though easy to get a hang on IMO.
One of the things you can do with your slaves is transforming them (not literally) into cows and bulls and stick them in the milking facility. You can be as good (letting them roam free and get milked at their own discretion) or as bad (sticking them in milking racks and force feed them) as you want, and you can even breed them yourself or between each other. (though unless you have the pregmod mod you can't raise the babies, you can only give them up)
There also societal decisions you can take to stir your arcology (the city you control) in the direction you want. One of them being transforming the city to Pastoralism and have them focus on creating and enjoying slave products. (you can even make other animal products illegal so everyone is forced to buy slave milk and sperm)