(Bloomberg) -- A prolonged shutdown at global meat supplier JBS SA could hit China the hardest as the country is the world’s biggest beef buyer and accounts for almost a third of the producer’s export revenue.China is also an important market for beef shipments from Australia, where a devastating cyberattack has halted JBS slaughter houses since the weekend, along with all its plants in the U.S. and at least one in Canada. Beef prices in China are already near a record, and any lengthy supply di