Horses have been sniffing track records since Laurel Race Course began its summer meeting Thursday, and yesterday Northern Wolf took a bite out of one.

The grayish colt sped six furlongs in 1 minute 8 1/5 seconds, winning the Duck Dance Handicap by about two lengths and improving Secret Emotion's 10-year-old track mark by two-fifths of a second.

Trained by former Washington Senators ballplayer Hank Allen, Northern Wolf turned fractions of :21 4/5, :44 3/5 and :56 1/5 on the way to his first stakes victory since April 1989.

He pushed past Amerrico's Bullet before the turn and controlled the race from there. "He gave me another gear I didn't think he had," said jockey Mike Luzzi.

Jeweler's Choice's late run was of no consequence to the winner, who paid $10.40 and earned $32,190. Kechi edged Two Eagles for third.

Born To Shop, the highweighted 4-to-5 favorite who had finished third or better 18 straight times, failed to show his customary speed and wound up fifth.

Since Laurel resumed live racing last week, the track has played extremely fast. But jockeys and trainers said it's hard to find fault with it.

"When you're galloping over it, you'd never think it's that fast," said jockey Joe Rocco. "It feels safe. I don't know what it is, but they're really running over it. You'll be sitting on a horse and look up and say, 'No way the horse went that fast.' "

Trainer Mike Pino, who won a career-best three races on Friday, said his horses came away with no apparent difficulties.

"For as fast as it is, it's not really a speed-favoring track," Pino said. "Horses are coming off {the pace}. The times are a little ridiculous, but I've got no problems with it, other than it's kind of deceiving as far as valuing horses."

John Passero, Laurel's track superintendent, said the composition of the track bears little change from previous summer sessions with a 3- to 3 1/4-inch cushion. He said he plans to add about 500 tons of sand to the dirt surface beginning this week to keep it tighter in wet conditions.

"I didn't think they'd run quite as quickly as they have been," Passero said. "But Laurel's generally a faster track {than Pimlico}. With those layers of stone underneath, it stays a little drier under there."

Jockey Allen Stacy said: "The track is fast, but it's good. They're not hitting the ground hard at all. You can listen to it and tell; they're not making a lot of noise out there."

Even the turf course produced unsually fast times yesterday. Kohen With a K., a former stakes winner who had found tough times recently, tied the six-furlong turf mark of 1:08 2/5 with his long-shot victory in the eighth race. He paid $135.80, winning his first since June 9, 1989, and topped an exacta worth $1,922.60. Roberson Injured

Jockey Brad Roberson suffered possible neck injuries when Departing Locks fell from apparent heat exhaustion about 40 feet before the wire in the ninth race, and Carlos Barrera was bruised when Classy Escort unseated him in the paddock before the seventh. Roberson, second-leading apprentice at the past Pimlico meeting, was taken for precautionary X-rays. Barrera is expected to ride today. . . .

This year's D.C. International at Laurel will be televised by ESPN, it was announced yesterday. The Oct. 21 race, which will anchor the two-day, five-race International Turf Festival, will be part of ESPN's hour-long "Racing Across America." ABC has televised the International the past three years.