China is on a global meat-buying spree, pushing up beef, pork and poultry prices around the globe as the world’s most populous nation scrambles to fill a large void in its meat supply. Meat buyers for China are ramping up purchases after a swine disease hit hog farms across the country and reduced its pig herd—the world’s largest—by more than a third. Domestic pork prices have surged and China’s meat imports are swelling in response, straining global supplies and sending ripples across the global economy. …