Stehly, G.R. and J.R. Meinertz. 1997. A bridging study for oxytetracycline in the edible fillet of rainbow trout: Analysis by a HPLC method and the official microbiological method. Submitted to the U.S. Food and Drug Administration, Center for Veterinary Medicine, August 26, 1997. 364 pages. The study was conducted in conjunction with the FDA Denver District Laboratory. The Denver District Laboratory was responsible for submitting their results from the official microbiological method to the Center for Veterinary Medicine. Oxytetracycline (OTC) fortified and incurred samples of rainbow trout fillet tissue were prepared at the UMESC. Portions of those samples were shipped to the Denver District Laboratory where they were processed to determine OTC concentrations. Incurred samples processed at the UMESC had OTC concentrations of 740, 1588, and 3944 ng/g. Method precision for those samples ranged from 0.5 to 2.2 %, respectively. The nominal OTC concentration in fortified samples ranged from 0.3 to 9.6 ng/g. Recovery of OTC from those samples ranged from 93 to 96 %.