About the Authors

Massaro W. Ueti

massaro@vetmed.wsu.edu

Affiliations Animal Diseases Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, Washington, United States of America, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America

Robert H. Mealey

Affiliation Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America

Lowell S. Kappmeyer

Affiliation Animal Diseases Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, Washington, United States of America

Stephen N. White

Affiliations Animal Diseases Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, Washington, United States of America, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America

Nancy Kumpula-McWhirter

Affiliation Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America

Angela M. Pelzel

Affiliation United States Department of Agriculture, Animal and Plant Health Inspection Service, Veterinary Services, Western Regional Office, Fort Collins, Colorado, United States of America

Juanita F. Grause

Affiliation Animal and Plant Health Inspection Service, Veterinary Services, National Veterinary Services Laboratories, Ames, Iowa, United States of America

Thomas O. Bunn

Affiliation Animal and Plant Health Inspection Service, Veterinary Services, National Veterinary Services Laboratories, Ames, Iowa, United States of America

Andy Schwartz

Affiliation Texas Animal Health Commission, Austin, Texas, United States of America

Josie L. Traub-Dargatz

Affiliation Department of Clinical Sciences, Animal Population Health Institute, Colorado State University, Fort Collins, Colorado, United States of America

Amy Hendrickson

Affiliation National Association of State Departments of Agriculture, Washington, District of Columbia, United States of America

Benjamin Espy

Affiliation Equine Reproduction, San Antonio, Texas, United States of America

Alan J. Guthrie

Affiliation Equine Research Centre, Faculty of Veterinary Science, University of Pretoria, Onderstepoort, South Africa

W. Kent Fowler

Affiliation California Department of Food and Agriculture, Sacramento, California, United States of America

Donald P. Knowles

Affiliations Animal Diseases Research Unit, Agricultural Research Service, United States Department of Agriculture, Pullman, Washington, United States of America, Department of Veterinary Microbiology and Pathology, Washington State University, Pullman, Washington, United States of America

Competing Interests

The authors have declared that no competing interests exist.

Author Contributions

Conceived and designed the experiments: MWU RHM DPK. Performed the experiments: LSK NKM. Analyzed the data: SNW LSK NKM JLTD TOB AS AH AJG WKF. Contributed reagents/materials/analysis tools: BE AMP JFG. Wrote the paper: MWU.