Market pressures, more so than laws and regulations, are likely to end the use of controversial practices in livestock production. The trend is already becoming visible, with major fast food chains and other restaurants prohibiting their suppliers from using gestation crates in hog production, said Joy Mench, professor at the University of California-Davis. The stalls are intended to prevent aggressive behavior among pregnant sows but are controversial because they restrict the animals’ movement. Mench said she expects the hog industry to end the use of crates within 10 to 15 years at the insistence of major pork buyers. “It won’t have been done through legislation. It will have been done by the retailers.”