scholarly journals Molecular Detection of the Virulence Genes in Escherichia coli Isolated from Healthy and Diarrheic Calves in Southern Iraq

2018 ◽  
Vol 26 (6) ◽  
pp. 1-10 ◽  
Author(s):  
Rasha Othman
2020 ◽  
Vol 8 (7) ◽  
pp. 1021 ◽  
Author(s):  
Samina Ievy ◽  
Md. Saiful Islam ◽  
Md. Abdus Sobur ◽  
Mithun Talukder ◽  
Md. Bahanur Rahman ◽  
...  

Avian pathogenic Escherichia coli (APEC) causes significant economic losses in poultry industries. Here, we determined for the first time in Bangladesh, the prevalence of APEC-associated virulence genes in E. coli isolated from layer farms and their antibiotic resistance patterns. A total of 99 samples comprising internal organs, feces, and air were collected from 32 layer farms. Isolation was performed by culturing samples on eosin–methylene blue agar plates, while the molecular detection of APEC was performed by PCR, and antibiograms were performed by disk diffusion. Among the samples, 36 were positive for the APEC-associated virulence genes fimC, iucD, and papC. Out of 36 isolates, 7, 18, and 11 were positive, respectively, for three virulence genes (papC, fimC, and iucD), two virulence genes, and a single virulence gene. Although the detection of virulence genes was significantly higher in the internal organs, the air and feces were also positive. The antibiograms revealed that all the isolates (100%) were resistant to ampicillin and tetracycline; 97.2%, to chloramphenicol and erythromycin; 55.5%, to enrofloxacin; 50.0%, to norfloxacin and ciprofloxacin; 19.4%, to streptomycin; 11.1%, to colistin; and 8.33%, to gentamicin. Interestingly, all the isolates were multidrug-resistant (MDR). Spearman’s rank correlation coefficient analysis revealed the strongest significant correlation between norfloxacin and ciprofloxacin resistance. This is the first study in Bangladesh describing the molecular detection of APEC in layer farms. Isolated APEC can now be used for detailed genetic characterization and assessing the impact on public health.


2016 ◽  
Vol 14 (1) ◽  
pp. 77-98
Author(s):  
Ibrahim E. Eldesouky ◽  
Hisham S. Nada ◽  
Talat H. Sheashe ◽  
Asmaa E Elshishiny

2021 ◽  
Vol 10 (1) ◽  
pp. 1-7

E. coli O157 is one of the main food-borne pathogens that attributed to the attaching and effacing Shigatoxigenic E. coli pathotype (AE-STEC). The occurrence of E. coli O157 in diarrheic calves investigated through molecular detection of rfbEO157 encoding gene was 8.02% within E. coli strains. Detection of AE-STEC virulence genes in E. coli O157 strains using multiplex PCR showed the presence of eae, stx1, stx2 and ehylA in percentages of 93.3, 73.3, 20 and 13.3%, respectively. The virulence genes profile of E. coli O157 revealed the predominance of eae+stx1 combination in 66.7% of these strains. All E. coli O157 strains exhibited antibiotic multi-resistances with higher resistance (100%) to amoxicillin/clavulanic acid, cefalexin, cefuroxime and tetracycline, while the lowest resistance was detected for gentamicin (40%). Phenotypic resistance to extended spectrum cephalosporins (ESCs) indicated that 60% of these strains were resistant to ceftriaxone and cefotaxime, while 53.3% were resistant to cefquinome. Molecular detection of extended spectrum β-lactamases (ESBLs) encoding genes recorded the superiority of blaTEM gene (100%), whereas the blaSHV and blaCTXM genes were detected in percentages of 40 and 20%, respectively. The genetic profiling of resistance genes revealed the role of blaCTXM gene in ESCs resistance as blaTEM+blaSHV+blaCTXM combination was detected only in ESC resistant strains. Finally, B2 phylogroup was the most prevalent one (80%) within E. coli O157 strains. This implicates diarrheic calves as a source of highly pathogenic multi-resistant E. coli O157 strains.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Destaw Asfaw Ali ◽  
Tesfaye Sisay Tesema ◽  
Yosef Deneke Belachew

AbstractDiarrheagenic Escherichia coli are a number of pathogenic E. coli strains that cause diarrheal infection both in animal and human hosts due to their virulence factors. A cross sectional study was conducted between November, 2016 and April, 2017 to isolate and molecularly detect pathogenic E. coli from diarrheic calves to determine the pathogenic strains, antibiogram and associated risk factors in Jimma town. Purposive sampling technique was used to collect 112 fecal samples from diarrheic calves. Conventional culture and biochemical methods were conducted to isolate E. coli isolates. Molecular method was followed to identify virulence factors of pathogenic E. coli strains. Antimicrobial sensitivity patterns of the isolates were tested using the Kirby–Bauer disk diffusion method. A structured questionnaire was also used to collect information from dairy farms and socio-demographic data. The overall isolation rate of E. coli in calves was 51.8% (58/112) (95% CI 42.0–61.0). The occurrence of the bacterium differed significantly by age, colostrum feeding time, amount of milk given per time and navel treatment (P < 0.05). Multivariable analysis revealed that the odds of being infected was significantly highest in calves which fed 1–1.5 L amount of milk per a time (OR 5.38, 95% CI 1.66–17.45, P = 0.005). The overall virulence genes detection rate was 53.5% (95% CI 40.0–67.0). Eleven (19.6%) of eaeA, 6 (10.7%) of Stx1 and 13 (23.2%) of Stx2 genes were detected from calves isolates. Except ciprofloxacillin, all isolates were resistant to at least one drug. Multi drug resistance was recorded in 68.0% (38/56) of calves isolates. Neomycin, 83.3% (25/30), followed by amoxicillin, 53.3% (16/30) were the highest resisted virulence genes. The study demonstrated considerable isolation rate, multiple antimicrobial resistant isolates and high resistant virulent genes in diarrheic calves. It also indicated that the potential importance of calves as source of pathogenic E. coli strains and resistant genes for human diarrhea infection. Improving the hygienic practice of farms and wise use of antimicrobials could help to reduce the occurrence of pathogenic E. coli in farms. Hence, further studies are needed to describe all virulent factors and serotypes associated with the emergence of drug resistant pathogenic E. coli strains in calves.


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