[Objective]The paper was to understand the resistance of commonly used clinical antibiotics to avian Escherichia coli and the inhibition of lactobacillus against pathogenic E.coli.[Method]The strain was isolated and i...[Objective]The paper was to understand the resistance of commonly used clinical antibiotics to avian Escherichia coli and the inhibition of lactobacillus against pathogenic E.coli.[Method]The strain was isolated and identified by SS medium culture,microscope examination,PCR amplification and biochemical test,and the sensitivity of avian E.coli to eight antibiotics was determined by disk diffusion method.Twelve strains of avian E.coli and one strain of lactobacillus were divided into five group using in vitro liquid culture method,namely simultaneous mixed culture group of lactobacillus and E.coli,first colonization group of E.coli,first colonization group of lactobacillus,E.coli control group and lactobacillus control group,for competitive inhibition test between E.coli and lactobacillus.[Result]Totally 34 strains with similar characteristics to E.coli strains were preliminarily screened;the target band amplified by PCR was 293 bp,which was consistent with the expected size.The isolated strain could decompose maltose,sucrose,lactose,glucose,arabinose,mannitol and sorbitol;the nitrate reduction test was positive,while citrate and V-P test was negative,consistent with the biochemical characteristics of E.coli.The resistance rate of the isolates to cefalexin and tylosin was over 65%,and that to enrofloxacin and doxycycline was up to 50%;the isolates were more sensitive to apramycin,tilmicosin,neomycin and colistin,and the total resistance rate was below 15%.The inhibitory effects of mixed culture of lactobacillus and E.coli against E.coli was better than first colonization of lactobacillus at 24 h;the inhibitory effects of first colonization of lactobacillus against E.coli was better than that of mixed culture of lactobacillus and E.coli at 36 h;the inhibitory effects of mixed culture of lactobacillus and E.coli against E.coli was the best at 48 h.[Conclusion]The isolated strains of E.coli were generally resistant to eight commonly used antibiotics.Lactobacillus could inhibit the growth of avian E.coli in vitro,and first colonization of lactobacillus received the best effort.展开更多
为确定江苏省徐州市某养鸭场病死鸭的病原菌,从发病鸭的肝中分离到1株细菌并命名为JSE 4,根据形态特征、培养特性、生化试验、16S r R N A分子鉴定结果可确定该菌为大肠杆菌(E.coli)。对该分离菌进行致病型快速鉴定、动物致病试验、毒...为确定江苏省徐州市某养鸭场病死鸭的病原菌,从发病鸭的肝中分离到1株细菌并命名为JSE 4,根据形态特征、培养特性、生化试验、16S r R N A分子鉴定结果可确定该菌为大肠杆菌(E.coli)。对该分离菌进行致病型快速鉴定、动物致病试验、毒力基因检测、药敏试验、系统发育分析,结果显示,该分离株为禽致病性大肠杆菌(APEC),可引起试验组SPF雏鸭死亡,死亡率为16.7%。分离株含有14种毒力基因中的12种,29种常用抗菌药物中,该分离株仅对链霉素、呋喃妥因、亚胺培南、呋喃唑酮、头孢他啶、氨曲南这6种药物具有敏感性。该分离株与源自比利时水源、瑞士禽肉源和中国鸭源分离株的亲缘关系最近,与比利时水源、瑞士禽肉源分离株的同源性高达99.7%。研究表明,从江苏徐州周边养鸭场病死鸭中分离到1株多重耐药的禽致病性大肠杆菌。展开更多
基金Major Science and Technology Innovation Project of Liaoning Province"Feed Quality and Safety Control and Low Protein Feed Project"(2019JH1/10200002).
文摘[Objective]The paper was to understand the resistance of commonly used clinical antibiotics to avian Escherichia coli and the inhibition of lactobacillus against pathogenic E.coli.[Method]The strain was isolated and identified by SS medium culture,microscope examination,PCR amplification and biochemical test,and the sensitivity of avian E.coli to eight antibiotics was determined by disk diffusion method.Twelve strains of avian E.coli and one strain of lactobacillus were divided into five group using in vitro liquid culture method,namely simultaneous mixed culture group of lactobacillus and E.coli,first colonization group of E.coli,first colonization group of lactobacillus,E.coli control group and lactobacillus control group,for competitive inhibition test between E.coli and lactobacillus.[Result]Totally 34 strains with similar characteristics to E.coli strains were preliminarily screened;the target band amplified by PCR was 293 bp,which was consistent with the expected size.The isolated strain could decompose maltose,sucrose,lactose,glucose,arabinose,mannitol and sorbitol;the nitrate reduction test was positive,while citrate and V-P test was negative,consistent with the biochemical characteristics of E.coli.The resistance rate of the isolates to cefalexin and tylosin was over 65%,and that to enrofloxacin and doxycycline was up to 50%;the isolates were more sensitive to apramycin,tilmicosin,neomycin and colistin,and the total resistance rate was below 15%.The inhibitory effects of mixed culture of lactobacillus and E.coli against E.coli was better than first colonization of lactobacillus at 24 h;the inhibitory effects of first colonization of lactobacillus against E.coli was better than that of mixed culture of lactobacillus and E.coli at 36 h;the inhibitory effects of mixed culture of lactobacillus and E.coli against E.coli was the best at 48 h.[Conclusion]The isolated strains of E.coli were generally resistant to eight commonly used antibiotics.Lactobacillus could inhibit the growth of avian E.coli in vitro,and first colonization of lactobacillus received the best effort.
文摘为确定江苏省徐州市某养鸭场病死鸭的病原菌,从发病鸭的肝中分离到1株细菌并命名为JSE 4,根据形态特征、培养特性、生化试验、16S r R N A分子鉴定结果可确定该菌为大肠杆菌(E.coli)。对该分离菌进行致病型快速鉴定、动物致病试验、毒力基因检测、药敏试验、系统发育分析,结果显示,该分离株为禽致病性大肠杆菌(APEC),可引起试验组SPF雏鸭死亡,死亡率为16.7%。分离株含有14种毒力基因中的12种,29种常用抗菌药物中,该分离株仅对链霉素、呋喃妥因、亚胺培南、呋喃唑酮、头孢他啶、氨曲南这6种药物具有敏感性。该分离株与源自比利时水源、瑞士禽肉源和中国鸭源分离株的亲缘关系最近,与比利时水源、瑞士禽肉源分离株的同源性高达99.7%。研究表明,从江苏徐州周边养鸭场病死鸭中分离到1株多重耐药的禽致病性大肠杆菌。
