1. Department of Pathology, Microbiology and Immunology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
2. School of Veterinary Medicine and Biomedical Sciences, University of Nebraska, Lincoln, NE 68588, USA
3. School of Natural Resources, University of Nebraska, Lincoln, NE 68588, USA
4. Department of Medicine and Epidemiology, School of Veterinary Medicine, University of California, Davis, CA 95616, USA
5. Department of Medicine, Institute of Medical Science, Universidade Federal do Rio de Janeiro, Macaé 27930-560, Brazil
6. Laboratory of Cell and Tissue Biology, Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, Rio de Janeiro 28013-602, Brazil