主要动物性食品生产链大肠杆菌的耐药性分析

为了解主要动物性食品生产链大肠杆菌(Escherichia coli)的耐药情况，采用美国临床和实验室标准协会（CLSI）推荐的微量肉汤稀释法，对源自猪肉、鸡蛋、鸡肉生产链的350株大肠杆菌进行常用10种抗菌药(组合)的敏感性测定，参考CLSI标准（2010）判定药敏结果。结果显示，350株大肠杆菌对四环素（TET）耐药率（82.0%）最高，其次是甲氧苄啶/磺胺甲噁唑（SXT）（75.4%），对庆大霉素（GEN）耐药率（26.9%）最低。尽管不同来源大肠杆菌对10种抗菌药中大部分药物耐药率较一致，但不同生产链环节的菌株耐药率却存在差异。76.2%（267株）受试菌株多重耐药，其中以8重耐药菌株（17.7%）最多。菌株共产生108种耐药谱，猪肉、鸡肉和鸡蛋生产链中大肠杆菌的耐药谱分别为40、46和55种，但优势耐药谱不明显。菌株数较多的耐药谱为：NAL-CIP-AMP-AMC-CEF-SPT-GEN-SXT-TET（21/350）、TET（20/350）、NAL-CIP-AMP-AMC-CEF-SPT-SXT-TET（16/350）、NAL-CIP-AMP-CEF-FLO-SPT-SXT-TET（16/350）及SPT-SXT-TET（15/350）。提示，主要动物性食品生产链大肠杆菌耐药情况较严重，应加强其耐药性连续监测与控制。

Drug Resistance of Escherichia coli Strains Isolated from the Production Chains of Main Animal Food

To understand drug resistance of Escherichia coli （E.coli） isolated from the production chains of main animal food，using trace dilution method recommended by clinical and laboratory standards institute CLSI broth，350 strains E.coli isolated from the production chains of pork，eggs and chickens were examined for sensitiveness against 10 kinds of antimicrobial agents （combination）. The results showed that 350 strains E.coli were mostly resistant to tetracycline （82.0%），followed by resistance to trimethoprim/sulfamethoxazole （75.4%），and the gentamycin drug resistant rate （26.9%）was the lowest. Despite the different origins of E.coli for the vast majority of these drugs were basically consistent， the resistance rate of the strains from different segments of animal food production chain was different.76.2% （267 strains） of the isolates were multi-drug resistant strains，the most of which were the eight kinds of drug-resistant strains （17.7%）. The whole test strains had 108 kinds of drug spectra， the spectra of E.coli isolated from the production chains of pork，eggs and chickens were 40，46 and 55，respectively，whereas the advantage drug resistance spectra were not obvious. The main drug resistance spectra included NAL-CIP-AMP-AMC-CEF-SPT-GEN-SXT-TET （21/350）， TET （20/350）， NAL-CIP-AMP-AMC-CEF-SPT-SXT-TET（16/350）， NAL-CIP-AMP-CEF-FLO-SPT-SXT-TET（16/350） and SPT-SXT-TET（15/350）. The results suggested the drug resistance of E.coli from the production chain of main animal food was serious，so it was necessary to strengthen the continuous monitoring and control.