Piechota M, Kot B, Zdunek E, Mitrus J, Wicha J, Wolska M K, Sachanowicz K
Pol J Vet Sci. 2014;17(3):407-11. doi: 10.2478/pjvs-2014-0058.
The aim of this study was to analyze by PCR 185 isolates of Staphylococcus from milk of cows with- and without mastitis and from the cowsheds environment for their potential ability to produce five classical staphylococcal enterotoxins. Among S. aureus isolates 8 (32%) carried enterotoxin genes and only 2 of them had more than one gene. The enterotoxin genes were detected in 22 (13.7%) coagulase-negative staphylococci (CNS) isolates, among them in 9 (11.4%) isolates of S. xylosus, 5 (16.7%) S. sciuri, 3 (10.3%) S. epidermidis and in 5 (22.7%) Staphylococcus spp. In some CNS 2 or 3 genes were detected simultaneously. Among the investigated enterotoxin genes, sec was the most prevalent (70%). The genes encoding enterotoxin B and D were detected in 5 (16.7%) and 6 (20%) isolates, respectively. The lowest number of isolates had sea and see genes. The genes encoding enterotoxins were often identified in staphylococci from milk of cows with mastitis (73.4% of detected genes), while only 6 (20%) isolates from milk of cows without mastitis and 2 (6.6%) isolates from cowshed environment were positive for enterotoxin genes. The results showed that CNS from bovine milk, like S. aureus, carried enterotoxin genes and may pose a risk for public health.
本研究旨在通过聚合酶链反应（PCR）分析来自患乳腺炎和未患乳腺炎奶牛的牛奶以及牛舍环境中的185株葡萄球菌，检测其产生五种经典葡萄球菌肠毒素的潜在能力。在金黄色葡萄球菌分离株中，8株（32%）携带肠毒素基因，其中只有2株携带不止一种基因。在22株（13.7%）凝固酶阴性葡萄球菌（CNS）分离株中检测到肠毒素基因，其中木糖葡萄球菌分离株中有9株（11.4%）、松鼠葡萄球菌分离株中有5株（16.7%）、表皮葡萄球菌分离株中有3株（10.3%）以及葡萄球菌属中有5株（22.7%）检测到该基因。在一些CNS中同时检测到2个或3个基因。在所研究的肠毒素基因中，sec最为普遍（70%）。分别在5株（16.7%）和6株（20%）分离株中检测到编码肠毒素B和D的基因。携带sea和see基因的分离株数量最少。产肠毒素基因在患乳腺炎奶牛的牛奶葡萄球菌中经常被鉴定出来（检测到的基因中有73.4%），而未患乳腺炎奶牛的牛奶中只有6株（20%）分离株以及牛舍环境中的2株（6.6%）分离株的肠毒素基因呈阳性。结果表明，牛乳中的CNS与金黄色葡萄球菌一样，携带肠毒素基因，可能对公共卫生构成风险。
