Pimlico announced yesterday that there will be a $100,000 increase in the purse of the Preakness Stakes of 1985. The additional money will bring the gross total for the 110th renewal of the 1 3/16-mile classic to $350,000.

Larry Abbundi, Pimlico director of racing, said, "In an effort to stay competitive with other 3-year-old races around the country we felt a purse increase was necessary. We've got to keep up with the Joneses."

Also being changed are the conditions of the race that will net $70,000 for second place instead of $50,000. Anyone wanting to enter the second leg of the Triple Crown without having been nominated for the race will have to pay a supplementary fee of $20,000; last year it cost $10,000.

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Chick Lang, Pimlico general manager, came back from New York with praise for a 2-year-old gelding trained by Woody Stephens named Cream Fraiche, winner of a seven-furlong maiden race at long odds. "Mighty Appealing was impressive even in defeat," Lang said. "But this young horse of Stephens' is promising too. We may hear some good things about him soon."

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Dean Gaudet, trainer of the talented colt Mighty Appealing, is hoping for a rematch with For Certain Doc, the Champagne winner. The pair is scheduled to meet Nov. 17 in the Remsen Stakes at Aqueduct.

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Charles Town will hold the first of seven Wednesday afternoon racing programs starting today at 1:30. Track officials say they hope to fill a void left when Laurel decided to shut down on Wednesdays.

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Linka, a former claiming filly trained by Tom Caviness, ran away from five rivals in yesterday's feature race. Long shot Her Donna closed well to be second, six lengths behind the winner and 1 1/2 lengths before Pretty Penny.

Linka was ridden by Michael Hunter, who drove her over the finish line in 1:10 4/5 for the six furlongs. She paid $3.20 and was the top part of a 1-5 exacta worth $22.40.