Oct 28 (Reuters) - Canada’s main stock index opened higher on Thursday, aided by gains in energy shares, although a slew of mixed corporate earnings limited further gains. At 9:32 a.m. ET (13:32 GMT), the Toronto Stock Exchange’s S&P/TSX composite index was up 52.33 points, or 0.25%, at 21,007.32. (Reporting by Amal S in Bengaluru; Editing by Ramakrishnan M.)