In order to maintain high milk production, you may rear your animals freely in the Curral Brasileiro, an open barn.
The corral will provide manure and liquid fertilizer. You may decide where the cows will graze when you set up the corral.
After that, you may either fence it off or let the animals run free on your land.
83 cows is the maximum capacity.
Expense: $82,000
Upkeep: $42 per day

Thanks to Naimog Mod