昆明地区鸡源沙门氏菌的分离鉴定及耐药性分析

Isolation, Identification and Drug Resistance of Salmonella from Chicken in Kunming

为了解昆明周边养鸡场的沙门氏菌耐药状况,采集昆明周边5家养殖场的50只疑似沙门氏菌病的发病鸡的肝脏和脾脏进行细菌分离,通过常规生化特性鉴定和PCR分子鉴定,然后通过药敏试验检测分离株耐药性,通过PCR技术对分离株的耐药基因进行检测。结果表明:共分离出8株沙门氏菌,8株菌的靛基质试验、尿素酶试验和VP试验结果均呈阴性,S3、S4菌株不产H2S,柠檬酸试验也呈阴性,针对沙门氏菌设计特异性引物进行扩增,得到目的条带495 bp,与预期一致;在药敏试验中,分离株对氨苄西林和头孢氨苄有较强的耐药性,对四环素中介耐药,对恩诺沙星、加替沙星、卡那霉素、庆大霉素以及氧氟沙星敏感,说明分离株已出现耐药性;在所检测的6种耐药基因中,β-内酰胺类的bla TEM-1和喹诺酮类的GyrA基因检出率为100%,四环素类的tetA基因未被检出,其他三种耐药基因aadA1、tetB和strB检出率均在50%以上,说明分离株耐药基因的携带率较高,需要引起养殖业的重视。

In order to understand the drug resistance of Salmonella in chicken farms around Kun‐ming, the liver and spleen of 50 chickens suspected of salmonellosis from 5 farms around Kunming were collected for bacterial isolation, identification of routine biochemical characteristics and molecular identification of PCR, then the drug resistance of the isolates was tested by tolerance test, the drug resistance genes of the isolates were detected by PCR. The results showed that 8 Salmonella were isolated, the results of ketole test, urease test and VP test of 8 Salmonella were negative, S3 and S4 did not produce H2 S, and citric acid test was negative. According to the specific design of the Salmonella bacteria primers were amplified to 495 bp, consistent with ex‐pectations. In the drug susceptibility test, the isolates showed strong resistance to ampicillin and cefalexin. medi-resistance to tetracycline, it is sensitive to enrofloxacin, gatifloxacin,kanamycin, gentamicin and ofloxacin. It indicated that the drug resistance of isolates had ap‐peared. Among the six drug-resistant genes detected, blaTEM-1 of beta-lactams and GyrA of quinolones were 100% and tetA of tetracyclines were not detected, the detection rates of the other three re‐sistance genes aadA1, tetB and strB were all above 50%. The results showed that the drug resis‐tance gene carrying rate of isolates was high, which should be paid attention to by the Poultry breeding industry.