Genomic and phenotypic characterization of Escherichia coli isolates recovered from the uterus of puerperal dairy cows

Abstract

The role of Escherichia coli in the pathogenesis of the puerperal uterine infection of the cow is largely unknown. It is proposed that E. coli favors the persistence of Arcanobacterium pyogenes and gram-negative bacteria that are pivotal to the establishment of the infection. Here, we report the genomic and phenotypic characteristics of 72 E. coli isolates recovered from the uterus of dairy cows with normal puerperium (n = 12; 35 isolates) or clinical metritis (n = 18; 37 isolates), in an attempt to identify characteristics that are related to the establishment of uterine infection. We evaluated DNA fingerprints generated by repetitive element sequence-based PCR, phylogenetic grouping, the presence of 15 virulence factor genes, in vitro biofilm formation and its relationship to curli fimbriae expression, and cellulose production. We found a wide genetic diversity (40 clonal types), including types common to normal puerperium and clinical metritis cows (n = 6), as well as types specific to normal puerperium (n = 14) or clinical metritis (n = 20) cows. Isolates were assigned to phylogenetic groups B1 (58%), A (31%), and D (11%). Only 4 virulence factor genes were detected (hlyE, hlyA, iuc, and eaeA). In vitro biofilm formation was significantly affected by culture medium and incubation temperature. Curli fimbriae expression and cellulose production, although related to biofilm formation, were not required for it. None of the evaluated E. coli characteristics were significantly related to the establishment of the uterine infection. In conclusion, data presented in this paper indicate that E. coli isolates recovered from the uterus of puerperal cows present a wide genetic diversity, do not belong to a known pathogenic group, and have a low potential of virulence and persistence. This corroborates the putative role of the bacterium in the pathogenesis of the puerperal uterine infection of the cow.

Specific Strains of Escherichia coli Are Pathogenic for the Endometrium of Cattle and Cause Pelvic Inflammatory Disease in Cattle and Mice

“…The consequences of uterine infection include reduced milk yield and infertility, which costs the USA dairy industry $650 million per annum [9]. Indeed, our study is not alone and there is emerging evidence from Europe and the USA that E. coli triplex B1 strains are prevalent in PID across several locations [32]. However, the evolutionary background of EnPEC is not clear.…”

Clinical efficacy of intrauterine cephapirin benzathine administration on clearance of uterine bacteria and subclinical endometritis in postpartum buffaloes

“…Extracted DNA was used for the amplification of specific virulent factors (VF) genes such as fimH gene of E. coli , fimA gene of A. pyogenes and lktA gene of F. necrophorum as per the thermal cycling parameters recommended by Bicalho, Machado, Oikonomou, Gilbert, and Bicalho () with slight modifications. The primer sequences for fimH, fimA and lktA gene were taken from previous studies of Moreno et al (), Silva et al () and Zhou, Bennett, and Hickford (), respectively). The primer sequences were synthesized by Genaxy Pvt.…”

Use of Antimicrobials in the Treatment of Reproductive Diseases in Cattle and Horses

“…In studies where bacteriological samples have been taken from the uterus, the clinical significance of the presence of each organism is difficult to assess (Silva et al. , ). The new, culture‐independent metagenomic methods have uncovered a large number species not reported in bovine uterine samples before, but again, their clinical relevance is completely unknown (Santos et al.…”

“…Under field conditions, bacteriological sampling of the uterus is usually not feasible, but selection of the antimicrobial is made on an empirical basis. In studies where bacteriological samples have been taken from the uterus, the clinical significance of the presence of each organism is difficult to assess (Silva et al 2008(Silva et al , 2009). The new, culture-independent metagenomic methods have uncovered a large number species not reported in bovine uterine samples before, but again, their clinical relevance is completely unknown (Santos et al 2011).…”

“…Few data on in vitro susceptibilities of bacteria isolated from the bovine uterus are available. E. coli isolated from the uterus are mostly of commensal type and could be compared with isolates from the bovine udder (Silva et al 2009). In principle, T. pyogenes and most anaerobic species are susceptible to benzylpenicillin and ampicillin in vitro (Jousimies-Somer et al 1996;VMD 2013).…”