The workers were charged Tuesday in Brown County with either two or three counts of mistreating animals. Each count carries a maximum penalty of nine months in prison and a $10,000 fine.
Video released in December by the animal rights group Mercy For Animals showed workers at Wiese Brothers Farm beating, kicking, stabbing and whipping sick and injured cows.
Farm owner Mark Wiese told The Associated Press at the time that he'd fired two workers and reassigned a third to duties that didn't involve animals. He did not immediately return a message left Thursday for comment on the charges.
Charged were Abelardo Jaimes, 31, of Menasha; Lucia Martinez, 39, of Wrightstown; Misael Monge-Minero, 33, of Green Bay; and Crescencio Pineda, 26, of Menasha.
All four are scheduled to make initial court appearances in Green Bay on March 4. Online court records don't list defense attorneys for them, and prosecutors weren't aware of their representation. The AP was unable to find home telephone numbers for any of the defendants.
The video clips show cows that are unable to stand being lifted with clamps or dragged with ropes and heavy equipment. Workers whip, kick and stab other cows to get them moving. One animal bleeds from cuts in its side, and another bleeds from its rear.
Wiese said he requires employees on his 5,000-cow farm who handle animals to review and sign its humane-treatment policy as part of the hiring process. The farm also provides training for workers caring for sick animals. He said after the video surfaced that the farm had taken additional steps to ensure proper treatment, including calling a supervisor to oversee care when an animal goes down and designating three workers as specialists to care for cows too sick or injured to stand.