may be from high receptor binding, or degradation and/or transportation outside of the joint.
Acknowledgments
Declaration of Ethics The Authors declare that they have adhered to the Principles of Veterinary Medical Ethics of the AVMA.
Conflict of Interest
This project was supported by the University of Minnesota Equine Center and The Minnesota Racing Commission with funds from the Minne- sota Agricultural Experiment Station (2013); and the American College of Veterinary Surgeon Foun- dation – Surgeon In-Training Grant (2013).