UPDATE 1-Canadian energy shares tumble with crude prices By: Reuters: Company News April 12, 2011 at 12:02 PM EDT * Canadian Oil Sands, Cenovus among losers (Adds analyst comments, updates prices) Read More >> Related Stocks: Cenovus Energy Inc Husky Energy Precision Drilling Corp Precision Drilling Corp S&P/TSX Composite Sempra Energy Suncor Energy Inc TSX Energy Index