1. Embrapa Pecuária Sudeste São Carlos São Paulo Brazil
2. Department of Small Animal Clinical Sciences, School of Veterinary Medicine and Biomedical Sciences Texas A&M University College Station Texas USA
3. Faculdade de Ciências Agrárias e Veterinárias Universidade Estadual Paulista (UNESP) Jaboticabal São Paulo Brazil
4. Department of Veterinary Pathobiology, School of Veterinary Medicine and Biomedical Sciences Texas A&M University College Station Texas USA