Brazilian Journal of Veterinary Research and Animal Science; Vol. 34 Núm. 3 (1997); 138-141 Brazilian Journal of Veterinary Research and Animal Science; Vol. 34 No. 3 (1997); 138-141 Brazilian Journal of Veterinary Research and Animal Science; v. 34 n. 3 (1997); 138-141 Brazilian Journal of Veterinary Research and Animal Science; V. 34 N. 3 (1997); 138-141 Brazilian Journal of Veterinary Research and Animal Science Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo (FMVZ-USP) instacron:USP