山东地区乳房炎和非乳房炎牛奶中金黄色葡萄球菌的分离鉴定与耐药分析

Isolation, Identification and Drug Resistance of Staphylococcus aureus from Mastitis and Non-mastitis Milk in Shandong

为了解山东地区不同类型牛奶中金黄色葡萄球菌流行情况和耐药特征,对37个牧场的乳房炎和非乳房炎奶样进行细菌分离鉴定及MIC测定试验。采用常规方法与PCR技术进行金黄色葡萄球菌的分离鉴定,微量肉汤稀释法进行MIC测定,卡方检验进行数据差异显著性分析。①共分离到150株金黄色葡萄球菌,检出率为11.26%(150/1332),且乳房炎奶样显著高于非乳房炎(P=0.009);②12种药物的MIC与EUCAST分布趋势大致相同;③分离菌株对青霉素(91.38%)耐药最严重,且乳房炎/非乳房炎奶样差异显著(P=0.047);④116株分离菌株中多重耐药(≥3)菌株为34(29.31%)株,乳房炎/非乳房炎奶样差异不显著(P=0.611);⑤威海对6种药物的耐药率在60%以上,其他地区仅对1~2种药物的耐药率在50%以上。乳房炎奶样的金黄色葡萄球菌检出率显著高于非乳房炎;分离菌株对青霉素严重耐药且乳房炎奶样多重耐药问题突出;不同地区均呈现不同程度的耐药。

To understand the prevalence and drug resistance of Staphylococcus aureus in different types of milk in Shandong, bacterial isolation, identification and minimal inhibitory concentration(MIC) test were carried out on mastitis and non-mastitis milk samples from 37 farms. The isolation and identification of Staphylococcus aureus were carried by conventional method and PCR technology, the MIC test was conducted with broth micro dilution methods and the data were analyzed by chi-square test. ①A total of 150 strains of Staphylococcus aureus were isolated with the detection rate of 11.26%(150/1332), and the milk samples of mastitis was significantly higher than that of non-mastitis(P=0.009). ② The distribution tend of MIC of 12 drugs was roughly the same as that of EUCAST. ③The isolated strains were the most resistant to penicillin(91.38%), and there was a significant difference in mastitis and non-mastitis milk samples(P=0.047). ④In 116 separation strains, there were 34(29.31%) strains of multiple resistance(≥3) and there was no significant difference in mastitis and non-mastitis milk(P=0.611). ⑤The resistance rate of six drugs in Weihai was more than 60% and the resistance rate of only one or two drugs in other regions was above 50%. The detection rate of Staphylococcus aureus in mastitis milk samples was significantly higher than that in non-mastitis milk samples.The isolated strain was highly resistant to penicillin and the problem of multiple drug resistance of mastitis milk samples was serious. Different regions showed different levels of drug resistance.