Coagulase gene polymorphism of Staphylococcus aureus isolated from clinical and sub-clinical bovine mastitis in Isfahan and Chaharmahal va Bakhtiari provinces of Iran

Mastitis is a common disease in dairy cattle and is an inflammatory response of the breast tissue to bacterial attack to this tissue. Mastitis causes considerable loss to the dairy industry, among the several bacterial pathogens that can cause mastitis; Staphylococcus aureus is probably the most lethal agent because it causes chronic and deep infection in the mammary glands that is extremely difficult to cure. Several virulence factors including coagulase gene are produced by S. aureus and may contribute to its pathogenicity. This study was conducted to investigate the coagulase gene polymorphism of S. aureus isolated from clinical and sub-clinical bovine mastitis milk samples in Isfahan and Chaharmahal va Bakhtiari provinces of Iran. Amplification of the coagulase gene from 86 S. aureus strains isolates by specific primers showed 31 specimens contained 970 bp fragment, and 11 strains contained 730 bp fragment relevant to coa gene (coagulase) in PCR. After enzymatic digestion with AluI, 31 specimens contained three bands: 320, 490, and 160 bp (genotype I) and 11 specimens contained two bands: 490 and 240 bp (genotype VIII) in the RFLP.