This work was performed to detect the Staphylococcus aureus gene, enterotoxins resistance to methicillin with the extraction of DNA directly from milk samples. Of the 200 samples studied 145 (72.5%) amplified the femA gene, which were analyzed regarding the presence of sea, seb, sec and mecA genes. The most prevalent enterotoxins genes were: sea (60%), seb (37.9%) and sec (6.9%). 18 milk samples (11 %) had S. aureus carrying the mecA gene. The detection of S. aureus directly from the milk, with no need for bacterial isolation and the characterization of the enterotoxigenic potential demonstrate that the PCR technique is very useful for epidemiological studies of staphylococcal infections of the mammary gland. The high percentage (72.5%) of positive milk samples for the presence of the femA gene suggests that S. aureus constitutes of the main agents which cause intramammary infections in the micro region of Sete Lagoas-MG and that its enterotoxigenic potential and the presence of the mecA gene, which identifies the S. aureus resistant to methicillin, represent a potential risk to public health.
Staphylococcus aureus; enterotoxins; MRSA; PCR
