银狐源沙门菌的分离鉴定、致病性及耐药性检测

Isolation,Identification,Pathogenicity and Drug Resistance of Salmonella from Diarrhea Silver Foxes

为了解秦皇岛地区不同养殖场中银狐源沙门菌致病性、耐药情况及耐药基因的携带情况,本研究2019—2021年采集秦皇岛地区不同养殖场中患腹泻病银狐的肛拭子、粪便等病料组织194份,采用RT-PCR、PCR方法对采集的样品检测其犬瘟热病毒、轮状病毒及犬细小病毒;采用细菌常规分离鉴定、PCR方法进行沙门菌鉴定,采用人工感染小白鼠试验、K-B药敏纸片法和PCR法分别检测沙门菌的致病性、耐药性及耐药基因型。结果显示,犬瘟热病毒、冠状病毒及犬细小病毒检测为阴性;从194份病料组织中分离得到101株沙门菌,其中78株沙门菌分离菌株对小白鼠具有致病,死亡率为40%~100%;78株致病性沙门菌对氨苄西林、阿莫西林、土霉素等9种药物耐药率在50%以上,对其他药物耐药率为5.1%~32.1%,以耐12、11、10种药物为主;耐药基因Sul1、Sul2、Sul3、aac(3)-Ⅰv、aac(6')-Ⅰb、TetA、TetM、TetR检出率在48.7%以上,其他耐药基因检出率为7.7%~21.8%,除了多粘菌素类药物,耐药表型与耐药基因之间存在相关性。本研究对该地区银狐源沙门菌病防控提供参考依据。

In order to understand the pathogenicity,drug resistance and genotypes of Salmonella,194 anal swabs,feces and other disease tissues were collected from diarrhea silver foxes on different farms from 2019 to 2021 in Qinhuangdao area for bacterial isolation as well as CDV,CPV and Rotavirus testing by RT-PCR and PCR.The isolated Salmonella was identified PCR.The pathogenicity,drug resistance and genotypes of Salmonella were studied via experimental infection in mice,K-B drug sensitivity paper method and PCR.The results showed that CDV,CPV and Rotavirus were negative and 101 Salmonella strains were isolated from these samples,of which 78 Salmonella strains were pathogenic to mice with the mortality of 40%-100%.The resistance rates of these pathogenic Salmonella strains were more than 50%to ampicillin,amoxicillin and oxytetracycline and 5.1%-32.1%to other drugs.More than 48.7%of drug resistance genes were Sul1,Sul2,Sul3,aac(3)-Ⅰv,aac(6')-Ⅰb,TetA,TetM and TetR detected in and 7.7%-21.8%were other genes.Except for polymyxin drugs,there was a correlation between drug resistance phenotype and genotypes.This study provided a reference for the prevention and control of Salmonella infection in silver foxes in this area.