MIAMI - Officials at Calder Race Course placed restrictions on a fourth barn on Thursday after a horse from the stable of Henry Suckie exhibited symptoms of a possible neurological disorder earlier that day.\nOn Monday, Calder placed a quarantine on the barn area and put restrictions on three of its barns when a horse from the stable of leading trainer Bill White tested positive for the equine herpesvirus. That horse was subsequently euthanized.\nTrack veterinarian Michelle Jobert said the Suckie horse was not walking properly, but it had no fever and was up to date on all vaccinations.\n"Naturally we are taking every precaution possible under the circumstance, so we have quarantined Barn 78 until test samples from the sick horse, which were shipped to the University of Kentucky in Lexington today, can be examined," Jobert said Thursday.\nJobert said results from those tests are expected back on Saturday.\n"If the tests are negative, we'll lift the quarantine in Barn 78," said Jobert. "The quarantine on the original three barns will remain in place regardless of the results."\nJobert also confirmed that a horse in one of the three barns under restrictions from Monday had contracted a fever earlier this week, with test results from that horse due back from the University of Kentucky by Friday.\nUnder the quarantine rules in effect, no horses can ship in or out of Calder for two weeks. Horses from the three barns originally affected cannot race or train with the general population for a three-week period, which began on Monday. In addition, no horse from Barn 78 will be allowed to race or train with the general population while under the restriction implemented Thursday.\nThe latest quarantine will put a further strain on a racing office now faced with filling an extra program per week, with Calder going from four days of racing a week to five days beginning next week. Thursday's eight-race program was inundated with late scratches. Friday's and Saturday's cards also are expected to be scratch-filled.\nCalder is not making any major changes in its schedule yet, said track vice president and general manager of racing John Marshall, although the track carded eight races Sunday instead of the usual nine. \nMarshall added that the track is working with the United States Department of Agriculture and the Florida Horsemen's Benevolent and Protective Association.\nCalder, he said, is "trying to take all measures to protect the local racing community in light of this situation."