1. Department of Molecular and Cellular Medicine, Texas A&M Health Science Center, College Station, TX 77843, USA.
2. Department of Biochemistry and Biophysics, Texas A&M University, College Station, TX 77843, USA.
3. Department of Animal and Avian Sciences, University of Maryland, College Park, MD 20742, USA.
4. Department of Biochemistry, University of Missouri, Columbia, MO 65211, USA.
5. Texas Veterinary Medicine Diagnostic Laboratory, College Station, TX 77843, USA.