中国动物传染病学报2025，Vol.33Issue(2)：194-199,6.
1株奶牛乳源弗氏柠檬酸杆菌的分离鉴定及耐药性分析
The Isolation,Identification and Drug Resistance Analysis of Citrobacter freundii from Dairy Cows
摘要
Abstract
To identify the potential pathogenic bacteria of bovine mastitis in a breeding farm in Chifeng City,Inner Mongolia,a strain of pathogenic bacteria(X-3)was isolated from the milk of the farm.Morphological observation,biochemical identification,construction of a phylogenetic tree based on 16S rDNA sequence,artificial infection of mice,detection of virulence genes,and Kirby Bauer(K-B)paper diffusion method were used to identify and analyze the isolated strains.The experimental results showed that the isolated strain was Citrobacter freundii,which has strong pathogenicity.Mice were intraperitoneally injected with 0.2 mL of Citrobacter freundii at a concentration of 1.5×107 CFU/mL,resulting in a mortality rate of 57.14％within 96 hours.Autopsy revealed bleeding spots in the lungs,resembling flower spots,liver congestion,and intestinal mucosal bleeding.According to virulence gene testing,the pathogen carries 7 virulence genes,namely cfa,ureD,ureE,ureF,ureG,viaB,and ompX.The drug sensitivity test results showed that the strains were only sensitive to 3 out of 15 antibiotics,including cefotaxime,levofloxacin,and florfenicol.The experimental results provide scientific basis for the isolation,identification,treatment,and diagnosis of Pseudomonas aeruginosa,and also provide reference data for the prevention and treatment of potential bacterial mastitis in dairy cows.关键词
牛乳/弗氏柠檬酸杆菌/分离鉴定/进化树分析Key words
Milk/Citrobacter freundii/separation and identification/phylogenetic analysis分类
农业科技引用本文复制引用
昭日格图,林鑫,毛冉,李清泉,合希格白音,韩晓华,于辰龙..1株奶牛乳源弗氏柠檬酸杆菌的分离鉴定及耐药性分析[J].中国动物传染病学报,2025,33(2):194-199,6.基金项目
赤峰市农牧科学研究所所内资助项目(2023CFNKS04) （2023CFNKS04）
内蒙古农牧业青年创新基金项目(2023QNJJM07) （2023QNJJM07）
齐齐哈尔市科技计划创新激励项目(CNYGG-2023022) （CNYGG-2023022）
