Tyson Foods Inc , the biggest U.S. meat processor, reported a 4 percent rise in quarterly sales, helped by higher demand for chicken and as the Hillshire Brands acquisition boosted sales of prepared foods. REUTERS: Tyson Foods Inc , the biggest U.S. meat processor, reported a 4 percent rise in quarterly sales, helped by higher demand for chicken and as the Hillshire Brands acquisition boosted sales of prepared foods.