Officials outlined the protocol for "milkshake" tests at Keeneland during an informational meeting April 6, and also told horsemen to be aware that some feed and supplements could help trigger a higher-than-normal TCO2 reading in a horse's blood.Effective April 8, opening day at the Lexington racetrack, blood will be drawn from all horses in to race about 45 minutes to post time. The samples must be taken in Barn 21, even if horsemen request that a private veterinarian take a sample.Samples will be drawn pre-race, but the tests performed post-race. Ohio State University will perform the tests the day after blood is drawn for racing Wednesdays through Fridays, and on Tuesdays for Saturday and Sunday racing. The testing device at the laboratory also will check for high levels of electrolytes.Milkshakes help reduce the build up of lactic acid in a horse's system, and thus are believed to enhance performance. The substance--usually bicarbonate of soda mixed with a liquid--is quickly absorbed into a horse's system and therefore most effective four to six hours before a race.The maximum allowable concentration of total carbon dioxide in serum is 37 millimoles per liter. Any reading over that would constitute an offense, the first of which is 24-hour detention--"earned surveillance"--for all horses in the trainer's barn for the remainder of the meet, which extends through April 29.Dr. Rick Sams of Ohio State and Dr. Mitzi Fisher, the Kentucky state vet, told horsemen to be wary of substances that can increase a horse's TCO2 level. Among them are some feed products and supplements, as well as basic baking soda."You need to be aware of any alkalinizing substances being administered to your horses," Sams said. "It carries risk. The administration of different substances, each of which may raise the level, provides an additive affect."Sams, in response to a comment that some racehorses regularly get a scoop of baking soda in their feed, said a one-pound box of baking soda could raise a horse's TCO2 level from 30-31 millimoles per liter to 37 millimoles per liter.Keeneland is the first Kentucky track to implement milkshake tests, but it must do so under "house rules" until Kentucky Horse Racing Authority regulations are on the books. If the regulations aren't official by the fall meet in early October, Keeneland will continue its own tests, track president Nick Nicholson said."Whether the authority does it or not, we are in this game to stay," Nicholson said. "We felt it was well worth it."The tests and support staff will cost Keeneland roughly $1,500 a day for 16 days of spring racing. The actual tests each run $8-$10.Keeneland director of racing Rogers Beasley said money isn't the issue. "It's just the right thing to do," he said.The Keeneland testing program follows the one in California. Del Mar began testing for milkshakes last summer in advance of having regulations on the books in California. Therefore, as in California, a positive test won't result in redistribution of the purse at Keeneland.