HALLANDALE BEACH, Fla. - Gulfstream Park officials late Thursday afternoon lifted the quarantine track management had implemented earlier that morning on one barn at the track and four others at its training center at Palm Meadows after an unidentified horse from trainer Jonathan Sheppard's barn displayed signs of a potential neurological disorder. According to Gulfstream's president and general manager, Steve Calabro, test results from samples taken from the stricken horse were found to be negative for the equine herpesvirus in a report received from the University of Kentucky in Lexington shortly after 4 p.m. on Thursday. "Naturally we are always concerned about the safety of our horses, so we imposed the quarantine as a precautionary measure," Calabro explained. "We are thrilled to see the test results come back negative and are able to lift the quarantine, return to business as usual and can look forward to a great weekend of racing." The short-lived quarantine affected horses trained not only by Sheppard but also those of trainers Todd Pletcher, Juan Vazquez and Steve Klesaris, all of whom are stabled in Barn 2 at Gulfstream Park. The quarantine was also imposed on barns 0, 11, 12 and 38 at Palm Meadows, three of which house horses trained by Pletcher - including the Eclipse-winning male juvenile of 2010, Uncle Mo - and the fourth horses from the stables of trainers Rick Violette and Saeed bin Suroor. Both Pletcher and Violette had horses ship in and out of Barn 2 at Gulfstream within the last several days. The one-day quarantine forced track officials to scratch six horses on Thursday's program, three trained by Pletcher, two by Klesaris and one by Sheppard. Regular training hours were shortened by 40 minutes at Gulfstream Park on Thursday to allow horses from Barn 2 to train outside the general population. Training is to return to normal on Friday.