1. Department of Population Health and Reproduction, School of Veterinary Medicine, University of California, Davis, 1089 Veterinary Medicine Drive, Davis, CA 95616
2. Department of Population Health, Poultry Diagnostic and Research Center, College of Veterinary Medicine, University of Georgia, 953 College Station Road, Athens, GA, 30602
3. Instituto Biologico, Centro Avançado de Pesquisa e Desenvolvimento em Sanidade Avicola, Descalvado, Sao Paulo, 13690-000, Brazil