Genomic characterization and antimicrobial susceptibility of bovine intrauterine Escherichia coli and its relationship with postpartum uterine infections

作     者：YANG Li-ming WANG Yi-hao PENG Yu MIN Jiang-tao HANG Su-qin ZHU Wei-yun 

作者机构：Laboratory of Gut Microbiology Nanjing Agricultural University 

出 版 物：《Journal of Integrative Agriculture》 (农业科学学报（英文版）)

年 卷 期：2016年第15卷第6期

页      面：1345-1354页

核心收录：

学科分类：090603[农学-临床兽医学] 09[农学] 0906[农学-兽医学] 

基　　金：supported by the National Key Technology R&D Program of China (2011BAD19B02) 

主　　题：postpartum dairy cow phylogenetic grouping genetic diversity virulence factor antimicrobial susceptibility 

摘      要：To investigate the roles of Escherichia coli in the pathogenesis of postpartum uterine diseases in dairy cows, a total of 145 E. coli isolates were recovered from 18 healthy cows （61 isolates） and 25 cows with clinical endometritis （84 isolates） at 25-35 days after parturition. Genomic characteristics including phylogenetic grouping, genetic diversity and virulence genes of E. coli isolates were screened to profile the characteristics related to uterine infections. The susceptibility of the bacteria against 23 antibiotics was also evaluated to support prevention and treatment of clinical cases. Genetic diversity of E. coli identified by random amplification of polymorphic DNA （RAPD） revealed 103 clonal types, including 3 common types to unaffected cows and endometritis cows, 39 types specific to healthy cows and 61 types in endometritis subjects. In addition, the isolates from endometritis uteri showed more genetic variability compared with that of healthy cows. Ac- cording to the findings of phylogenetic grouping, the E. coil isolates were assigned to group A （35.9%）, B1 （59.3%） and D （4.8%）. The expression of 10 of 20 virulence gens were detected positively, and only fimH gene was revealed significantly （P〈0.05） associated with endometritis. From antimicrobial susceptibility test, E. coli was found highly resistant to tetracy- cline, ampicillin, carbenicillin and amoxicillin, but sensitive to amikacin, netilmicin, tobramycin, cefepime and ceftazidime. In conclusion, E. cofiwere extensively observed in both healthy and endometritis cows, and presented a large clonal types, however, fimH was the only gene observed associated with clinical endometritis. Our results suggest that the drugs like amikacin, netilmicin, tobramycin and cefepime could be considered for preventing and treating clinical endometritis in the practical management of dairy cow.