Act of Duty, a half-brother to Northern Afleet who sold for $3.6 million as a yearling but failed to win on the racetrack, has been retired and will stand in 2006 at Arthur Appleton's Bridlewood Farm near Ocala, Fla.The 5-year-old horse will stand for a syndicate that includes Bridlewood, Stonehedge Farm South, and WinStar Farm. No stud fee was announced.By Mr. Prospector, Act of Duty is out of the Nureyev mare Nuryette. His half-brother, Northern Afleet, is by Afleet, a son of Mr. Prospector. Northern Afleet has been in the news this year because he is the sire of Preakness (gr. I) and Belmont Stakes (gr. I) winner Afleet Alex. Act of Duty is also a half-brother to grade I winner Tap to Music (by Pleasant Tap).Act of Duty was bred in Kentucky by Warner L. Jones Farm and sold at the 2001 Keeneland July sale by Three Chimneys Farm, agent. He was purchased by John Ferguson for Sheikh Mohammed and made two starts in England at three and one start this year in Dubai. "Act of Duty is by far the best looking son of Mr. Prospector I have ever seen, and with the recent success of his brother Northern Afleet, and his superstar son Afleet Alex, I feel this horse will offer huge opportunities to the Florida Breeder." George G. Isaacs, general manager of Bridlewood said.