(Adds analyst comment, market details, updates prices to close)
* TSX ends down 9.62 points, or 0.07 percent, at 13,494.36
* Index rises 5 pct in March, best month since October 2011
By Alastair Sharp
TORONTO, March 31 (Reuters) - Canada's main stock index ended slightly lower on Thursday as losses for materials and financial stocks canceled out advances for energy stocks, whose recent strength helped the index notch its best monthly performance in more than four years.
The Toronto Stock Exchange's S&P/TSX composite index gained 5 percent in March, its biggest monthly move higher since October 2011, with its recovery from a swoon to start the year helped by a rebound in oil prices.
"In terms of the quarter, it's been a bit of a rollercoaster ride," said Michael Sprung, president at Sprung Investment Management.
He said he questioned the sustainability of the rally given it was likely boosted by short covering and that a handful of geopolitical risks stand ready to trigger a selloff.
"This is a time to be fairly cautious," he said, recommending selective accumulation in energy and materials as well as in insurance companies and some industrial stocks.
On the day, the S&P/TSX index ended down 9.62 points, or 0.07 percent, at 13,494.36.
The energy group climbed 0.9 percent as oil prices were steady to firmer at the end of their best month in almost a year.
The most influential gainers on the index included two of its biggest energy companies: Suncor Energy Inc, which rose 1.5 percent to C$36.17, and Canadian Natural Resources Ltd , which added 1.4 percent to C$35.13.
The heavyweight financials group slipped 0.2 percent, while the materials group, which includes precious and base metals miners and fertilizer companies, lost 1.4 percent.
Mining company Silver Wheaton Corp's shares fell 5.8 percent to C$21.55 after it increased the number of new shares it planned to issue under a previously announced financing deal, while fertilizer company Potash Corp fell 2.1 percent to C$21.55.
Toronto-Dominion Bank slipped 0.4 percent to C$56.06 after it said it expected losses from bad loans in the oil and gas sector to be manageable given its relatively limited exposure sector.
Cara Operations Ltd rose 9.4 percent to C$29.15 after the owner of the Swiss Chalet and Harvey's restaurant chains said it would buy St-Hubert BBQ, one of Quebec's largest casual dining chains, for C$537 million ($415 million).
Shares of Valeant Pharmaceuticals International Inc fell 3 percent to C$34.05 after a regulator sent its management a cease-trade order. The drugmaker is seeking more time to file its annual report, as it risks defaulting on its $30 billion debt if it misses the current April 29 deadline. (Additional reporting by Fergal Smith in Toronto; Editing by Bill Trott and Matthew Lewis)