1. Smithsonian National Zoological Park, Smithsonian Zoo and Conservation Biology Institute, 3001 Connecticut Ave. NW, Washington, DC 20008, USA
2. Department of Comparative Diagnostic and Population Medicine, College of Veterinary Medicine, University of Florida, 2015 SW 16th Ave., Gainesville, Florida 32608, USA
3. Department of Large Animal Clinical Sciences, University of Florida–College of Veterinary Medicine, 2015 SW 16th Ave., Gainesville, Florida 32608, USA