1. Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota, USA
2. Department of Veterinary and Biomedical Sciences, College of Veterinary Medicine, University of Minnesota, St. Paul, Minnesota, USA
3. Department of Veterinary Health & Reproduction, School of Veterinary Medicine, University of California, Davis, California, USA
4. Department of Anthropology and Animal Behavior Graduate Group, University of California, Davis, California, USA