*** I guess he cracked the 'ol whip one too many times! LOL *** LAS VEGAS (Reuters) - Famed Las Vegas magician Roy Horn of the "Siegfried and Roy" duo remained in critical but stable condition on Saturday after being mauled by a white tiger during a performance on his 59th birthday, his spokesman said. The 7-year-old male tiger, named Montecore, grabbed Horn's forearm about halfway into the Friday night performance at the Mirage hotel-casino, witnesses said. When Horn tried to fend the tiger off with his microphone, the tiger lunged and bit him on the left side of the neck, causing profuse blood loss, they said. Horn was conscious when he was rushed to University Medical Center and underwent about two hours of surgery, said his spokesman, Dave Kirvin. "It's just sad and extremely unfortunate. The doctors are encouraged that he will recover, but it will be several days until the full extent of his injury is known," Kirvin said. Spectators were horrified by the scene. "There were a couple of gasps, and people thought it was part of the act, and then it was real quiet," audience member Paul D'Antonio, who was sitting about 15 feet from the stage, told the Las Vegas Review-Journal. "It literally drug him by his neck off the stage like a rag doll," D'Antonio said. In a mid-day news conference, Alan Feldman, a spokesman for MGM Mirage, said Horn's status had not changed and declined to comment on reports he had gone back into surgery. "It's a very serious situation," Feldman said. "He's obviously under constant supervision by a team of doctors. They're keeping an eye on things quite literally every moment." The show has been canceled through Christmas and refunds will be issued, he said. The tiger was being quarantined, Feldman said, declining to say what would happen to it. Horn's partner, 64-year-old Siegfried Fischbacher, spent most of the night at the hospital, Kirvin said. "He is shocked and devastated," he added. Horn turned 59 on Friday. "The last place Roy would place blame would be with the animal," said Bernie Yuman, manager for "Siegfried and Roy." Although Horn had told the crowd it was the tiger's first performance, the animal has been performing for years, Kirvin said. There have been no attacks in the more than 5,000 shows the two men have performed at the hotel since 1990, he said. White tigers and lions are a trademark of the German-born illusionists, who have been putting on one of the most famous shows in Las Vegas for more than 30 years. Horn, born in Nordenham, Germany, and Siegfried, of Rosenheim, Germany, have performed worldwide since meeting in 1959. When he was 7, Horn's "beloved pet Hexe" saved his life, according to the duo's Web site. It does not say what type of pet it was.