The biggest contributor to the TSX loss was Toronto-Dominion Bank, pulling 7.6 points from the index. Energy was the heaviest sector drag, with 32.3 net points. 

Leading the index were Canada Goose Holdings Inc , up 30 percent in the wake of its quarterly results, Paramount Resources Ltd , up 4 percent, and Prometic Life Sciences Inc , higher by 3.3 percent.

Lagging shares were Precision Drilling Corp , down 7.1 percent, First Majestic Silver Corp, down 5.8 percent, and Teck Resources Ltd, lower by 5.3 percent.

On the TSX 122 issues advanced and 121 declined as a 1-to-1 ratio favored advancers. There were 17 new highs and 3 new lows, with total volume of 419.7 million shares.

The most heavily traded shares by volume were Prometic Life Sciences Inc , Bombardier Inc  and Cenovus Energy Inc.

The TSX's energy group  fell 2.98 points, or 1.51 percent.

West Texas Intermediate crude futures fell 3.38 percent, or $2.26, to $64.63 a barrel. Brent crude  fell 3.56 percent, or $2.7, to $73.24 [O/R]

The TSX is up 0.6 percent for the year.

(Reporting by Chuck Mikolajczak)