PCR and PCR-RFLP genotyping of Staphylococcus aureus coagulase gene: convenience compared to pulse-field gel electrophoresis

Abstract

Staphylococcus aureus belongs to the group of major contagious mastitis pathogens. We aimed to evaluate the usefulness and the convenience of the coagulase (coa) gene polymorphism to type S. aureus from bovine mastitis milk samples. A total of 22 S. aureus strains were collected from bovine cases of mastitis in four veterinary practices in the Rhone-Alpes region of France and were assessed using coagulase gene’s polymerase chain reaction (PCR) followed by AluI PCR-restriction fragment length polymorphism (PCR-RFLP). Coa gene PCR produced six profiles. The AluI PCR-RFLP displayed nine profiles, giving ten combined patterns. Two genotypes accounted for 50 % of the isolates. Although the results showed that cows from the studied regions were infected by S. aureus strains harboring more than one coagulase genotype, only one or two types predominated. Identification based on PCR-RFLP of the coa gene gave the same results than pulse-field gel electrophoresis (PFGE). Identification based on PCR-RFLP of the coa gene has been considered a more simple and accurate typing method for epidemiological investigations of bovine mastitis.