1. Department of Surgery, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, SP 05508 270, Brazil.
2. Independant Veterinarian, Alameda do Parque 400, Jd Plaza Athene, Itu, SP 13302 225, Brazil.
3. Department of Clinical Medicine, School of Veterinary Medicine and Animal Science, University of São Paulo, São Paulo, SP 05508 270, Brazil.