IN the "every cloud has a silver lining" department, mandarins at the Department of Agriculture are privately hoping for an upside from Russia's decision to ban all British dairy products. As a result, the mayor of Moscow, supposedly the world's biggest beef buyer, is sending a representative to Dublin next week to visit the giant Horizons Food Fair. Advance hoopla for the fair is already well underway, with the German manufacturers promising that "the best wurst is yet to come".