The whereabouts of John Tammaro Jr. still remained a mystery as of Sunday, one week after the trainer disappeared."There's been no word and no trace," said son Mike, who traveled from his base in Maryland to South Florida to oversee his father's stable, "We looked at all the canals and I didn't see any place a car might have gone in. I don't think there is anything else we can do."The 75-year-old trainer was last reported seen by Gulfstream security guard John Moleski as he left the track at approximately 10 a.m. following training hours on the morning of Feb. 25. "He was the color of a yellow shirt," Moleski said, "I've known him for years and had never seen him look so sick."Tammaro had been battling health problems during the last few years and was recovering from recent surgery to correct a liver imbalance, although Mike said that he recently got a clean bill of health from his physicians and "was doing better than he had in a while."Andy Kasper, spokesman for the Hallandale Beach Police Department, indicated that an investigation was still underway. "The primary concerns are the first steps," he noted, "We're covering all of the routes he might have taken, covering all hospitals and all of the local restaurants."Kasper would not predict what further steps might be taken in the search, although Mike mentioned that consideration was being given to diving in the canals between Gulfstream and Tammaro's home in Pembroke Pines in order to locate the beige 1987 Mercedes 420 that the trainer drove.