Zilkha, a 2-year-old filly out of 2010 Horse of the Year Zenyatta, had her first workout at Santa Anita on Wednesday, exercising three furlongs in 38.40 seconds.  “We wanted to show her the track,” trainer John Shirreffs said.  Zilkha, by Candy Ride, arrived at Santa Anita and the Shirreffs stable earlier this month, having undergone early training in Florida.  :: Serious horseplayers use serious products. Get DRF's premium past performances, now free for the first time Shirreffs said on Friday that he is hopeful Zilkha can start at the Del Mar summer meeting, which runs from July 22 to Sept. 11.  “That’s what we’d like to do,” he said.  Zilkha is the fourth foal to reach the racetrack out of Zenyatta, who won 19 of 20 starts and earned $7,304,580, all for owners Jerry and Ann Moss and Shirreffs. An immensely popular racehorse, Zenyatta won her first 19 races, including the 2009 Breeders’ Cup Classic at Santa Anita, and was beaten a head by Blame in her final start in the BC Classic at Churchill Downs in 2010.  None of Zenyatta’s first three foals to reach the track – Cozmic One, Zellda or Ziconic – won a race. Cozmic One made five starts, while Ziconic was winless in 12 starts. Zellda did not race.