 The measure, which passed with 55 percent approval, outlaws caging pigs in gestation stalls, which are metal enclosures that measure two feet across and prevent sows from turning around freely.In 2006, Arizona residents voted on Proposition 204, which requires that pregnant pigs and calves raised for veal be kept in enclosures large enough that they can turn around and fully extend their limbs by December 31, 2012.A majority of voters, 62 percent, approved the measure, known as the Humane Treatment of Farm Animals Act, which received funding from Farm Sanctuary.