California will soon release the results of a study that will reflect trends in connection with blood samples taken from about 6,000 racehorses for the purpose of “milkshake” –or TCO2 testing– last year.

California takes blood from all Thoroughbreds 30 minutes before post time. Samples are tested within 120 hours of collection; the maximum allowable TCO2 reading is 37 millimoles per liter in plasma.

Dr. Scott Stanley, associate professor at the University of California-Davis Animal Health and Food Safety Laboratory, discussed TCO2 testing July 14 as part of the National Horsemen’s Benevolent and Protective Association Medication Committee meeting in Minneapolis. He said officials in California already have noticed trends.

From more than 60,000 samples, TCO2 readings have been as low as 18.3 millimoles and as high as 44.8 millimoles, according to Stanley’s report. The mean reading is 31.5, plus or minus 2.06