Authors : Z. Dendani, M.A. Arcangioli, P. Bezille, R. Ouzrout and N. Laouabdia Sellami
Abstract: Thirty-two strains of Staphylococcus aureus have been collected in the setting of an epidemiological investigation in Rhone-Alps region in France (collaboration AFSSA-ENV Lyon) from samples of milk of districts of thirty-two cows affected by clinical mastitis, belonging to 17 herds, on one period of 5 months (January 2007 to May 2007). This set of withdrawals has been achieved in 4 veterinary clienteles situated in Rhone-Alps. Twenty five strains of Staphylococcus aureus were the object of identification phenotypic and a genetic characterization. Epidemiological scorers have been taken, the profiles of resistance to the antibiotics, the profiles of Pulsed Field Gel Electrophoresis (PFGE). The one has been chosen here because of its excellent power of discrimination. A sensitivity of 89% of the isolates to all tested antibiotics has been determined by the method of disk by diffusion on agar Mueller Hinton (MH) (Sanofi Diagnosis Pasteur or Bio-Rad). The frequencies of resistance to the Penicillin to the ampicillin to the oxacillin to the Cefquinome to the Cefalotin and to the Amoxicillin + AC clavulanique is respectively 20, 08, 08, 08, 08 and 04%, those to the trimethoprime more the sulfamethoxazole and the Sulfamethoxypyridazine are 08 and 24%. No resistance of the strains of Staphylococcus aureus to the oxytetracycline to the Doxycycline to the erythromycin to the Spiramycin to the Lincomycin to the Gentamicin and to the Enrofloxacine. The molecular typage by Pulsed-Field Gel Electrophoresis (PFGE), after digestion of the chromosomal DNA of the isolates with the SmaI endonuclease restriction, revealed 09 different genetic profils (A-I). The two main pulsotypes A and B represented 58% together and have been found in 64% of studied exploitations. So the strains of Staphylococcus aureus are in majority of the genotype A and B. They belonged to the predominant genotypes and could have a certain predilection to cause some mastitis among the dairy cow. In spite of the heterogeneity of the some, the results of the PFGE are in favor of a dissemination of a small number limited of predominant genotypes.
Z. Dendani, M.A. Arcangioli, P. Bezille, R. Ouzrout and N. Laouabdia Sellami, 2010. Genotyping of Staphylococcus aureus Isolated from Bovine Clinical Mastitis by Pulsed-Field Gel Electrophoresis (PFGE). Journal of Animal and Veterinary Advances, 9: 5-11.