In this study, the enterotoxigenic potential of Staphylococcus strains (n = 574) isolated from raw milk samples (n = 140) was determined for their capacity to produce
staphylococcal enterotoxins. In addition, the relationship between the presence of
enterotoxins,
coagulase, and
thermonuclease (
Tnase) was assessed. The results showed that 19% of Staphylococcus was enterotoxigenic, being able to produce at least one of the
staphylococcal enterotoxins (A, B, C, and D). Most of the strains were able to produce
enterotoxin D (68.8%), whereas 12.8% of the Staphylococcus strains were able to produce
staphylococcal enterotoxin A. Besides, the production of more than one type of
enterotoxins by the same strain was observed.
Tnase was considered the best marker for enterotoxigenic potential of isolates, although some of them were negative for
coagulase and
Tnase but positive for
enterotoxin production. Therefore, either the use of
Tnase to assess Staphylococcus enterotoxigenic potential or the use of simple and easy screening tests for
enterotoxin production should receive more attention when evaluating the pathogenic potential of foodborne Staphylococcus strains. Due to the association of both
coagulase positive Staphylococcus and
coagulase negative Staphylococcus with
foodborne disease outbreaks, regulators and industries should pay more attention to enterotoxigenic Staphylococcus rather than focusing only on S. aureus or
coagulase positive Staphylococcus. Finally, data found here suggest a high risk of staphylococcal intoxication with the consumption of raw milk or dairy products made from raw milk.