1. Microbiology and Parasitology Department-CIC, Faculty of Veterinary Sciences, University of La Plata, 60 y 118, B1900AVW, La Plata, Argentina
2. National Animal Sanitary Service (SENASA), Paseo Colón 367, 1063, Buenos Aires, Argentina
3. CIC-CCV & INTA, CC 77, 1708, Morón, Buenos Aires, Argentina
4. Statistics Department, Faculty of Veterinary Sciences, University of La Plata, 60 y 118, B1900AVW, La Plata, Argentina