Sheila C Rahal1, Maria J Mamprim, Evelyn H G Caporali, Carlos R Teixeira. 1. Department of Veterinary Surgery and Anesthesiology, Faculty of Veterinary Medicine and Animal Science, UNESP Botucatu, Caixa Postal 560, Rubião Júnior, s/n, CEP: 18618-000, Botucatu, SP, Brazil.