South Park Episode 604 - "Fun with Veal"

When the boys learn where veal comes from on a field trip to the local slaughterhouse, they instantly turn into junior eco-terrorists (call Tom Ridge!). After calf-napping all the future parmigiana meat in town, the boys blockade themselves in Stan's bedroom, where Stan develops a "genital" disease from his diet of fruits and vegetables. Maybe tortured baby cow meat really does a body good.