1. K. L. Maddy Equine Analytical Chemistry Laboratory, School of Veterinary Medicine; University of California; Davis California USA
2. Department of Veterinary Molecular Biosciences, School of Veterinary Medicine; University of California; Davis California USA
3. School of Veterinary Medicine; University of California; Davis California USA
4. National Veterinary Institute (SVA); Uppsala Sweden
5. Uppsala University; Uppsala Sweden
6. Center for Preventive Doping Research - Institute of Biochemistry; German Sport University; Cologne Germany
7. Department of Population Health and Reproduction, School of Veterinary Medicine; University of California; Davis California USA