Half the world's pigs -- more than 470 million of them -- live in China, but even that may not be enough to satisfy the growing Chinese appetite for meat. While meat consumption in the United States has fallen more than 5 percent since peaking in 2007, Chinese meat consumption has leapt 18 percent, from 64 million to 78 million (metric) tons -- twice as much as in the United States. Pork is by far China's favorite protein, which helps to explain the late-May announced acquisition of U.S. meat giant Smithfield Foods Inc., the world's leading pork producer, by the Chinese company Shuanghui International, owner of China's largest meat processor.