LEXINGTON, Ky. - Gus Koch's birthday on Sept. 26 will mark a special milestone: it will be the longtime Claiborne farm manager's last day at work.\nIt's hard to think of Koch, 62, as a retiree. He's been working in the Thoroughbred business since 1970, when he left the Marine Corps and started by hauling feed at Stoner Creek Stud under legendary farm manager Charles Kenney. He joined Claiborne on Sept. 1, 1978, after a five-year stint at E.P. Taylor's Windfields. From the start, his career path has intersected with those of numerous great racehorses, stallions, and mares.\n"I started out with Count Fleet over at Stoner Creek," said Koch, whose name is pronounced "cook."\nCount Fleet, in fact, made both a professional and personal highlight for Koch. He met his wife, Theresa, one Sunday in front of the 1943 Triple Crown winner's stall when she and her sister happened to visit Stoner Creek when the stallion was colicking. They've been married 39 years now.\nA lot has changed since Koch started work in the 1970s. Sales prices have climbed, and so have stallions' book sizes. The game has become big business, and technology has made some things simpler and others more complicated.\n"We used to send a postcard to the owners and tell them their mares had foaled, and now it's done with e-mail, faxes, and pictures on the Internet," Koch said. "Communication is so convenient now, and clients expect it and deserve it.\n"But the big thing for farm managers now is the vet issues. Now we have vaccines for botulism and paste wormers, where before we had to tube everything. We vaccinated for many more diseases than we used to. Angular limb deformities we handle differently now. We have glue-on shoes and surgeries like periosteal elevation and screw-and-wire. We have ultrasound now. It's a different game now. It's a lot more technical and complicated. It's not for me to say whether some of these things are good or bad, but we're all more informed now, that's for sure."\nKoch is the son of a turf writer, Charles R. Koch, whose beat covered Ohio racing, Keeneland, and the sales. Young Gus accompanied him to all of these and got a well-rounded view of the sport early in life. Gus's first horse was a former lead pony from Latonia Downs.\nGus's own children - there are 10 of them, five sons and five daughters - learned to lead horses with Moccasin, the only juvenile filly ever to earn Horse of the Year honors, which she did in 1965. (She also was dam of English and Irish juvenile champion Apalachee, two-time Irish champion Belted Earl, and five other stakes winners.)\nKoch has gotten close to some of the horses along the way.\n"Nijinsky was one of my favorites, because I worked for E.P. Taylor, who bred him," Koch said. "He had Northern Dancer when I was working there in Maryland, and then Nijinsky was here at Claiborne when I came here. Then of course he sired Ferdinand, who won the '86 Derby for the Kecks, who were clients. Nijinsky had a lot of trouble with lymphangitis (severe leg swelling), and I spent a lot of time with that horse nursing him along. He was always special to me.\n"I got to go to Florida to bring Mr. Prospector here when he came to Kentucky, and I was here for Danzig's whole career. Round Table was here when I was here, and I was here for most of Secretariat's career."\nHe lived through many of the great stallions' entire careers, and he helped bury some greats, too. The toughest, perhaps, were champions Easy Goer, who died unexpectedly of heart failure at age 8, and Swale, the 1984 Kentucky Derby winner who also died of a heart attack eight days after winning the Belmont.\n"On a Sunday morning, I went in to town and helped build Swale's coffin, while some other men stayed and dug a grave for him," Koch recalled. "It was a huge loss to Claiborne. A well-bred horse and a very good racehorse. We don't know the potential we lost that day. I think it was probably huge."\nSwale's Derby was one of only two Koch saw in person (the other was Winning Colors's in 1988, when Claiborne's Forty Niner was second). Every other year, he was running the breeding shed that Saturday.\nKoch has been associated with so many good horses it's impossible to list them all on a single page of this newspaper. In many cases, he's familiar not only with the individuals, but whole lines. Take Monarchy and Dorine. Monarchy, a full sister to Round Table, produced Narrate, whose daughter Preach is the dam of Pulpit. Dorine was the dam of 1988 Broodmare of the Year Grecian Banner. That makes her the second dam of Personal Ensign, who begat My Flag, who begat Storm Flag Flying. You get the idea.\n"I love foaling season, the breeding season," Koch said. "It's an exciting time, seeing that newborn foal on the ground. The potential is there, the promise, and it's a fresh start."\nIt's time for fresh start for Koch. He won't be leaving the Thoroughbred game entirely. He and his sons own Rebel Raider, a 2-year-old Monarchos gelding. Six of his children are involved in the sport in one way or another, including Charles and Matthew. With partner Ted Kuster, they operate the Shawhan Place farm adjacent to Gus Koch's place. It's a fair bet Gus will make time to offer some good advice and horsemanship.\n"I've been around some great, great horses, and some great, great people, and when I look back at that, it's pretty exciting," Koch said. "I want especially to thank Seth and Clay and Dell Hancock. What an honor it's been to work for them at Claiborne. It's been a pretty good trip."