摘要
[目的]对新疆维吾尔自治区奶牛隐性乳腺炎常见致病菌进行分离、鉴定,评价头孢洛宁和利福昔明对临床分离菌株的体外抗菌效果.[方法]采用兰州隐性乳腺炎诊断液对新疆维吾尔自治区昌吉回族自治州某奶牛养殖场的干乳期奶牛进行诊断;利用平板划线法及细菌 16S rDNA序列分析法对采集的 74 份乳样进行细菌分离及种属鉴定;应用微量肉汤稀释法测定头孢洛宁和利福昔明对致病菌临床分离株的最低抑菌浓度(MIC)以及最低杀菌浓度(MBC).[结果]从 74 份乳样中共分离、鉴定致病菌9 种、103 株,其中,金黄色葡萄球菌 35 株,占总菌株数量的 33.98%;大肠杆菌 24 株,占总菌株数量的23.30%;产色葡萄球菌 15 株,占总菌株数量的 14.56%;模仿葡萄球菌(10 株)、表皮葡萄球菌(6 株)、屎肠球菌(5 株)、溶血性葡萄球菌(4 株)、地衣芽孢杆菌(3 株)和腐生葡萄球菌(1 株)的数量分别占总菌株数量的 9.70%、5.83%、4.85%、3.88%、2.91%、0.97%.体外抗菌试验结果显示,头孢洛宁对金黄色葡萄球菌、大肠杆菌、产色葡萄球菌、溶血性葡萄球菌、表皮葡萄球菌、腐生葡萄球菌、屎肠球菌、模仿葡萄球菌和地衣芽孢杆菌的MIC分别为 0.12、3.91、0.98、0.06、0.98、0.98、3.91、0.06、0.49 μg/mL,MBC分别为 0.24、7.81、1.95、0.12、1.95、1.95、7.81、0.24、1.95 μg/mL;利福昔明对金黄色葡萄球菌、大肠杆菌、产色葡萄球菌、溶血性葡萄球菌、表皮葡萄球菌、腐生葡萄球菌、屎肠球菌、模仿葡萄球菌和地衣芽孢杆菌的MIC 分别为 0.20、6.25、1.56、0.78、1.56、1.56、12.50、0.20、0.20 μg/mL,MBC 分别为 0.78、12.50、3.13、1.56、3.13、3.13、12.50、0.78、1.56 μg/mL.[结论]引起该养殖场干乳期奶牛隐性乳腺炎的主要致病菌为金黄色葡萄球菌、大肠杆菌、产色葡萄球菌;头孢洛宁和利福昔明对临床分离的致病菌株均有良好的抑菌效果.
Abstract
[Objective]This study was conducted to isolate and identify the common pathogenic bacteria associated with subclinical mastitis in dairy cows in Xinjiang Uygur Autonomous Region,and to evaluate the in vitro antibacterial effects of cefalonium and rifaximin against the clinical bacterial isolates.[Method]The subclinical mastitis in dairy cows in dry period in a dairy farm in Changji Hui Autonomous Prefecture,Xinjiang Uygur Autonomous Region was diagnosed using Lanzhou mastitis test(LMT).The bacterial isolation and species identification of a total of 74 collected milk samples were performed using streak plate method and 16S rDNA sequence analysis method.The minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)of cefalonium and rifaximin against the clinical isolates were determined by micro-broth dilution method.[Result]A total of 103 pathogenic bacterial isolates belonging to 9 species were obtained from the 74 milk samples.Among them,Staphylococcus aureus(S.aureus,n =35),Escherichia coli(E.coli,n =24)and Staphylococcus chromogenes(S.chromogenes,n=15)were found as the dominant species,accounting for 33.98%,23.30%and 14.56%of the total number of the isolates,respectively.Staphylococcus simulans(S.simulans,n =10),Staphylococcus epidermidis(S.epidermidis,n=6),Enterococcus faecium(E.faecium,n=5),Staphylococcus haemolyticus(S.haemolyticus,n=4),Bacillus licheniformis(B.licheniformis,n=3)and Staphylococcus saprophyticus(S.saprophyticus,n=1)were also observed,accounting for 9.70%,5.83%,4.85%,3.88%,2.91%and 0.97%of the total number of the isolates,respectively.The in vitro antibacterial test showed that the MICs of cefalonium against S.aureus,E.coli,S.chromogenes,S.haemolyticus,S.epidermidis,S.saprophyticus,E.faecium,S.simulans and B.licheniformis were 0.12,3.91,0.98,0.06,0.98,0.98,3.91,0.06 and 0.49 μg/mL,respectively,and the corresponding MBCs were 0.24,7.81,1.95,0.12,1.95,1.95,7.81,0.24 and 1.95 μg/mL,respectively.The MICs of rifaximin against S.aureus,E.coli,S.chromogenes,S.haemolyticus,S.epidermidis,S.saprophyticus,E.faecium,S.simulans and B.licheniformis were 0.20,6.25,1.56,0.78,1.56,1.56,12.50,0.20 and 0.20 μg/mL,respectively,and the corresponding MBCs were 0.78,12.50,3.13,1.56,3.13,3.13,12.50,0.78 and 1.56 μg/mL,respectively.[Conclusion]The main pathogenic bacteria causing subclinical mastitis in dairy cows in dry period in this farm were S.aureus,E.coli and S.chromogenes.Both cefalonium and rifaximin had good antibacterial effects against the clinical isolates.
基金项目
新疆维吾尔自治区区域协同创新专项(科技援疆计划)项目(2022E02014)
国家科技期刊平台
NSTL
维普
万方数据