广东省鸭疫里氏杆菌耐药性调查及floR传播分子特征研究
发布时间：2018-07-18 07:13
【摘要】：鸭疫里氏杆菌感染具有发病率高、死亡率高的特点,是目前引起世界范围内水禽感染的重要疾病,同时也是造成养鸭业经济损失的主要疾病之一。由于鸭疫里氏杆菌极易产生耐药性,因此给临床治疗带来了极大的困扰。目前关于鸭疫里氏杆菌耐药性的研究报道还比较少,尤其是关于分子耐药机制和传播机制的研究鲜有报道。2013年2月至2015年7月,从广东省9个地区收集具有典型鸭疫里氏杆菌病症状的病(死)鸭和鹅的脑、肝组织样品,分离培养鸭疫里氏杆菌。采用特异性PCR方法进行分子学鉴定,同时采用全自动微生物鉴定仪来鉴定疑似菌株,共分离得到115株鸭疫里氏杆菌,其中鸭源54株,鹅源61株。用琼脂二倍稀释法测定32种抗菌药物的敏感性。药敏结果显示,分离株有很高的耐药性,有103株(89.6%)鸭疫里氏杆菌分离株存在多重耐药现象。采用PCR和测序方法对115株分离菌进行了耐药基因和整合子类型检测和分析。结果显示:共有5大类抗生素的25种耐药基因被检测出来。在鸭疫里氏杆菌分离株中首次检测出三种氨基糖苷磷酸转移酶基因aph(3’)-Ⅱ、aph(3’)-Ⅳ、aph(4’)-Ⅰa,氨基糖苷转移酶基因aad B,红霉素耐药基因erm B、erm C和磺胺类抗菌药物耐药的sul3。9株鸭疫里氏杆菌株含有1类整合子,其中6株携带978bp大小的aad A2基因盒和3株携带2287bp大小的aac(6’)-Ⅱ-cat B3-aad A1基因盒。对分离得到的菌株进行Sma I-PFGE分子分型,共有58株分型成功,得到16种不同的Sma I-PFGE型(以相似度≥90%为判定标准),包括11个簇和5个单一型。本研究中的鸭疫里氏杆菌分离株存在广泛的克隆传播,且克隆传播存在于不同种属的宿主动物(鸭和鹅)间及相同、不同地区间分离到的菌株中。为探究抗生素耐药性与生物膜的相关性,用结晶紫染色的方法定量测定生物膜形成能力。结果表明,有95(82.6%)株鸭疫里氏杆菌分离株具有产膜能力,其中40(34.8%)株是强产膜菌株,且对12~23种抗菌药物具有抗药性;25(21.7%)中等产膜株和30(26.1%)弱产膜菌株可对7~12种种抗菌药物耐药。20(17.4%)株没有产膜能力,耐药种数小于等于6种。可以看出生物膜形成能力与耐药谱的种数之间存在一定的关系。此外,通过S1-PFGE和杂交的方法确定鸭疫里氏杆菌中flo R基因既位于染色体上也位于质粒上,发现在13株鸭疫里氏杆菌中存在一个新型携带flo R基因的质粒,其大小23kb,与之前的报道的质粒不同。通过接合转移和质粒稳定性实验等方法证明这个新型质粒可以转移到与之不同种属的大肠杆菌工程菌C600中,转移频率为10~(-6)~10~(-9),但是稳定性很差。
[Abstract]:Richter Duck infection is an important disease that causes worldwide waterfowl infection with high incidence and high mortality. It is also one of the major diseases that cause economic losses in duck industry. It is very difficult for the clinical treatment because of the resistance of Ribrella canalicus to drug resistance. At present, there are few reports on drug resistance of Rim Duck, especially on the mechanism of molecular resistance and transmission. From February 2013 to July 2015, The brain and liver tissue samples of dead ducks and geese with typical symptoms of Ribrella duck were collected from 9 regions of Guangdong Province and isolated and cultured. The molecular identification was carried out by specific PCR, and the suspected strains were identified by automatic microbiological identification instrument. A total of 115 strains of Riemiella Duck were isolated, of which 54 were from ducks and 61 from geese. The sensitivity of 32 antimicrobial agents was determined by Agar double dilution method. The results of antimicrobial susceptibility showed that the isolates had high drug resistance and 103 strains (89.6%) had multiple drug resistance. The resistance genes and integron types of 115 isolates were detected and analyzed by PCR and sequencing. The results showed that a total of 25 resistant genes of 5 major antibiotics were detected. Three aminoglycoside phosphotransferase gene aph (3')-鈪，
本文编号：2131153
[Abstract]:Richter Duck infection is an important disease that causes worldwide waterfowl infection with high incidence and high mortality. It is also one of the major diseases that cause economic losses in duck industry. It is very difficult for the clinical treatment because of the resistance of Ribrella canalicus to drug resistance. At present, there are few reports on drug resistance of Rim Duck, especially on the mechanism of molecular resistance and transmission. From February 2013 to July 2015, The brain and liver tissue samples of dead ducks and geese with typical symptoms of Ribrella duck were collected from 9 regions of Guangdong Province and isolated and cultured. The molecular identification was carried out by specific PCR, and the suspected strains were identified by automatic microbiological identification instrument. A total of 115 strains of Riemiella Duck were isolated, of which 54 were from ducks and 61 from geese. The sensitivity of 32 antimicrobial agents was determined by Agar double dilution method. The results of antimicrobial susceptibility showed that the isolates had high drug resistance and 103 strains (89.6%) had multiple drug resistance. The resistance genes and integron types of 115 isolates were detected and analyzed by PCR and sequencing. The results showed that a total of 25 resistant genes of 5 major antibiotics were detected. Three aminoglycoside phosphotransferase gene aph (3')-鈪，
本文编号：2131153
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