HEIDELBERG, South Africa (AP) — South Africa embarked on a mass vaccination of cattle on Friday to stem an outbreak of foot-and-mouth disease that threatens to disrupt meat, dairy and livestock supplies and exports. The outbreak, which started intensifying late last year and has rapidly spread across the country’s livestock industry, has already affected more than 297,000 cattle and resulted in over 120 000 animals being culled as farmers try to contain the spread. The outbreak threatens mass