目的 了解合肥市养殖屠宰环节中肉鸡沙门菌的带菌率、血清型分布、抗生素耐药谱分布以及脉冲场凝胶电泳(PFGE)分子分型情况,为合肥市食品安全提供科学的基础数据,为进一步加强合肥市公共卫生安全提供科学依据。方法 2010年7－9月对合肥市10家肉鸡养殖场和14家屠宰户分别采用肛拭法和胴体漂洗法采集45份肉鸡活体和45份肉鸡胴体标本,根据GB/T 4789.4－2010对沙门菌进行分离、鉴定以及血清学分析;并采用PCR方法进行复核鉴定;对最终确定的阳性菌株使用临床实验室标准化协会(CLSI)推荐的纸片法进行药敏试验;同时采用PFGE方法确定其分子分型。结果 在45份肉鸡活体样本中未检出沙门菌;45份肉鸡胴体样本中检出12株沙门菌,检出率为26.7%,经PCR复核检测,所分离的12株沙门菌对invA和hilA基因的携带率均为100%;12株沙门菌分为3种血清型,其中9株为印第安纳沙门菌,2株为鼠伤寒沙门菌,1株为肠炎沙门菌;12株沙门菌对实验中所采用的15种抗生素总耐药以及多重耐药菌株数均为10株;12株沙门菌共分出7种PFGE带型,9株印第安纳沙门菌共分离出5种不同的PFGE带型;同一血清型的沙门菌分子分型结果,基本位于同一大簇中;相同PFGE带型的菌株,耐药谱非常接近。结论 合肥市肉鸡胴体沙门菌检出率高,沙门菌的血清型、药敏性以及基因型具有多样性特征,耐药现象严重,相同PFGE带型的菌株,耐药谱非常接近。
Objective To investigate the contamination, serotypes and antibiotic resistance profiles of Salmonella, and its genotypes determined by pulsed-field gel electrophoresis (PFGE) in broiler chickens during breeding and slaughtering processing in Hefei, China, and to provide scientific baseline data for the food safety and a scientific basis for strengthening the public health security in Hefei. Methods From July to September 2010, the anal swab method and carcass rinsing method were used to collect samples from 45 live broilers and 45 broiler carcasses in 10 broiler farms and 14 slaughter houses in Hefei. According to GB/T 4789.4-2010, Salmonella was isolated and identified and then subjected to serological analysis; PCR was used for identification of suspected Salmonella isolates. The disk diffusion method recommended by the Clinical and Laboratory Standards Institute was used for testing the drug sensitivity of the finally identified Salmonella strains. PFGE was used for genotyping of these Salmonella strains. Results No Salmonella strain was detected in the 45 live broiler samples; 12 Salmonella strains were detected in the 45 broiler carcass samples, with a detection rate of 26.7%. The PCR testing indicated that all the 12 Salmonella strains carried genes invA and hilA. The serological analysis showed that among the 12 Salmonella strains, 9 were S. indiana, 2 were S. typhimurium, and 1 was S. enteritidis. Ten of the 12 Salmonella strains were resistant to the 15 antibiotics used in the experiment; also, 10 strains developed multi?drug resistance. Seven types of PFGE patterns were identified among the 12 Salmonella strains, and 5 types among the 9 strains of S. indiana. The genotyping showed that the Salmonella strains of the same serotype were almost in the same large cluster. The Salmonella strains of the same PFGE pattern had similar antibiotic resistance profiles. Conclusion In Hefei, the Salmonella detection rate among broiler carcasses is high; Salmonella strains are diverse in serotypes, drug sensitivity profiles, and genotypes; many of them are resistant to multiple antibiotics, and the strains of the same PFGE pattern have similar antibiotic resistance profiles.
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