Genotypes and enterotoxin gene content of S. aureus isolates from poultry.

Little is still known about the genotypes and prevalence of enterotoxin genes in animal-derived Staphylococcus aureus strains. In this study, spa type, the presence of known enterotoxin genes, and mecA gene was determined in 42 S. aureus isolates from poultry. All these isolates were classified as mecA-negative. t002, found in 19 staphylococci, was the most prevalent spa type in the studied population. t034 was found in 11 isolates. MLST performed on three t034 isolates confirmed its attachment to ST398. A strong association between the CC5 genetic background and the egc gene grouping in staphylococci of animal origin was confirmed, since all 23 isolates with t002, t214, and t010, belonging to CC5, contained egc1. No enterotoxin genes were found in 15 S. aureus isolates. In this population the most prevalent genotype was t034, found in 11 isolates. It was demonstrated that MSSA strains with the t034 ST398 genetic background also occur in poultry. This may imply, that ST398-type strains occur in a wider range of livestock species than previously believed.