1. Department of Clinical-Surgical, Diagnostic and Pediatric Sciences, University of Pavia, Pavia, Italy
2. Department of Biology and Biotechnology “L. Spallanzani”, University of Pavia, Pavia, Italy
3. Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna “B. Ubertini”, Pavia, Italy