CANADA STOCKS-TSX ends slightly lower as banks weigh, Valeant pulls back

TORONTO, April 23 (Reuters) - Canada's main stock index closed slightly lower on Wednesday as Valeant Pharmaceuticals International Inc shares pulled back after an acquisition-backed bump the day before and heavyweight banks also weighed. The Toronto Stock Exchange's S&P/TSX composite index unofficially ended down 22.58 points, or 0.16 percent, at 14,533.39. (Reporting by Alastair Sharp; Editing by Meredith Mazzilli)