MILAN/VICENZA (Reuters) – Italy’s biggest cooperative banks are bracing for a wave of mergers following a government reform that forces them to convert into joint stock companies within 18 months. The reform aims to strengthen Italy’s banking sector, which fared the worst in a Europe-wide health check of lenders last year. The government says it will also ultimately support bank lending to businesses, which has been shrinking for the past three years as Italy grappled with its longest post-war recession.