Resistant bacteria can be transmitted to humans through feces or contaminated meat from local chickens. Bacterial strains were isolated from the intestinal contents of 400 local chicken samples from various sales site...Resistant bacteria can be transmitted to humans through feces or contaminated meat from local chickens. Bacterial strains were isolated from the intestinal contents of 400 local chicken samples from various sales sites. These strains were then characterized using bacteriological and biochemical methods to identify resistant strains. In a study conducted in Ouagadougou, we systematically collected chicken fecal samples from 20 locations across the city, followed by isolation and identification of Salmonella spp. using specific enrichment and culture methods, as well as Escherichia coli. Bacterial strains were characterized using antibiotic resistance profiles were determined through agar diffusion tests, revealing sensitivity or resistance to a range of antibiotics based on established scientific criteria. The results showed that out of the 400 samples collected, 81.25% and 63.5% were contaminated by Escherichia coli and Salmonella spp., respectively. Among these, 86.15% of identified Escherichia coli and 50.78% of Salmonella spp. displayed resistance to at least one tested antibiotic. Among 280 Escherichia coli isolates identified resistant to at least one antibiotic, 31.07% were resistant to cefotaxime (CTX), 20.35% to ceftazidime (CAZ), 21.07% to ceftriaxone (CTR), 75% to amoxicillin clavulanic acid (AMC), 23.57% aztreoname (ATM) and 27.14% were resistant to imipenem (IMP). In the case of the 129 Salmonella spp. isolates resistant to at least one tested antibiotic, 34.88% were resistant to CTX;41.08% to CAZ;35.65% to CTR, 92% to AMC, 39.53% to ATM and finally 47.28% were resistant to IMP. Our study revealed high prevalence of resistance in bacterial strains isolated from local chickens sold outdoors in Ouagadougou. These findings raise significant public health concerns, due to the possible transmission of these resistant strains to humans through the consumption of contaminated meat, thus complicating the treatment of bacterial infections.展开更多
Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity ag...Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity against E.coli O157:H7 than using either alone.This study aimed to explore responses underlying the antibacterial mechanisms of kojic acid and tea polyphenols from the gene level.The functional enrichment analysis by comparing kojic acid and tea polyphenols individually or synergistically against E.coli O157:H7 found that acid resistance systems in kojic acid were activated,and the cell membrane and genomic DNA were destructed in the cells,resulting in“oxygen starvation”.The oxidative stress response triggered by tea polyphenols inhibited both sulfur uptake and the synthesis of ATP,which affected the bacteria's life metabolic process.Interestingly,we found that kojic acid combined with tea polyphenols hindered the uptake of iron that played an essential role in the synthesis of DNA,respiration,tricarboxylic acid cycle.The results suggested that the iron uptake pathways may represent a novel approach for kojic acid and tea polyphenols synergistically against E.coli O157:H7 and provided a theoretical basis for bacterial pathogen control in the food industry.展开更多
An extensively drug-resistant(XDR)Escherichia coli strain 258E was isolated from an anal swab sample of a chicken farm of Anhui province in China.Genomic analyses indicated that the strain 258E harbors an incompatibil...An extensively drug-resistant(XDR)Escherichia coli strain 258E was isolated from an anal swab sample of a chicken farm of Anhui province in China.Genomic analyses indicated that the strain 258E harbors an incompatibility group N(IncN)plasmid pEC258-3,which co-produces bla_(CTX-M-3),bla_(KPC-2),bla_(TEM-1B),qnrS1,aac(6')-Ib-cr,dfrA14,arr-3,and aac(6')-Ib3.Multiple genome arrangement analyses indicated that pEC258-3 is highly homologous with pCRKP-1-KPC discovered in Klebsiella pneumoniae from a patient.Furthermore,conjugation experiments proved that plasmid pEC258-3 can be transferred horizontally and may pose a significant potential threat in animals,community and hospital settings.展开更多
BACKGROUND The association between the intestinal microbiota and psychiatric disorders is becoming increasingly apparent.The gut microbiota contributes to colorectal carcinogenesis(CRC),as demonstrated with colibactin...BACKGROUND The association between the intestinal microbiota and psychiatric disorders is becoming increasingly apparent.The gut microbiota contributes to colorectal carcinogenesis(CRC),as demonstrated with colibactin-producing Escherichia coli(CoPEC).AIM To evaluate the association between CoPEC prevalence and anxiety-and depressive-like behaviors with both preclinical and clinical approaches.METHODS Patients followed after a CRC surgery and for whom the prevalence of CoPEC has been investigated underwent a psychiatric interview.Results were compared according to the CoPEC colonization.In parallel C57BL6/J wild type mice and mice with a CRC susceptibility were chronically infected with a CoPEC strain.Their behavior was assessed using the Elevated Plus Maze test,the Forced Swimming Test and the Behavior recognition system PhenoTyper®.RESULTS In a limited cohort,all patients with CoPEC colonization presented with psychiatric disorders several years before cancer diagnosis,whereas only one patient(17%)without CoPEC did.This result was confirmed in C57BL6/J wildtype mice and in a CRC susceptibility mouse model(adenomatous polyposis colimultiple intestinal neoplasia/+).Mice exhibited a significant increase in anxiety-and depressive-like behaviors after chronic infection with a CoPEC strain.CONCLUSION This finding provides the first evidence that CoPEC infection can induce microbiota-gut-brain axis disturbances in addition to its procarcinogenic properties.展开更多
Avian pathogenic Escherichia coli(APEC)belonging to extraintestinal pathogenic E.coli(ExPEC)can cause severe infections in extraintestinal tissues in birds and humans,such as the lungs and blood.MprA(microcin producti...Avian pathogenic Escherichia coli(APEC)belonging to extraintestinal pathogenic E.coli(ExPEC)can cause severe infections in extraintestinal tissues in birds and humans,such as the lungs and blood.MprA(microcin production regulation,locus A,herein renamed AbsR,a blood survival regulator),a member of the MarR(multiple antibiotic resistance regulator)transcriptional regulator family,governs the expression of capsule biosynthetic genes in human ExPEC and represents a promising druggable target for antimicrobials.However,a deep understanding of the AbsR regulatory mechanism as well as its regulon is lacking.In this study,we present a systems-level analysis of the APEC AbsR regulon using ChIP-Seq(chromatin immunoprecipitation sequencing)and RNA-Seq(RNA sequencing)methods.We found that AbsR directly regulates 99 genes and indirectly regulates 667 genes.Furthermore,we showed that:1)AbsR contributes to antiphagocytotic effects by macrophages and virulence in a mouse model for systemic infection by directly activating the capsular gene cluster;2)AbsR positively impacts biofilm formation via direct regulation of the T2SS(type II secretion system)but plays a marginal role in virulence;and 3)AbsR directly upregulates the acid tolerance signaling system EvgAS to withstand acid stress but is dispensable in ExPEC virulence.Finally,our data indicate that the role of AbsR in virulence gene regulation is relatively conserved in ExPEC strains.Altogether,this study provides a comprehensive analysis of the AbsR regulon and regulatory mechanism,and our data suggest that AbsR likely influences virulence primarily through the control of capsule production.Interestingly,we found that AbsR severely represses the expression of the type I-F CRISPR(clustered regularly interspaced short palindromic repeats)-Cas(CRISPR associated)systems,which could have implications in CRISPR biology and application.展开更多
Escherichia coli is the commonest bacterial uropathogen of UTIs, the commonest infections in immunocompromised diabetic patients. Better understanding of their main resistance mechanisms to commonly used antibacterial...Escherichia coli is the commonest bacterial uropathogen of UTIs, the commonest infections in immunocompromised diabetic patients. Better understanding of their main resistance mechanisms to commonly used antibacterial agents will help to reduce the burden of this infection. The prevalence of drug resistant uropathogenic Escherichia coli isolates from immunocompromised diabetic patients attending selected health facilities in Benue State was investigated. Two hundred and ninety-six midstream urine samples were collected for both study and control diabetic patients. Bacterial isolation was done using semi-quantitative method. Drug resistant Escherichia coli were identified as multidrug resistant (MDR), extensive drug resistant (XDR) and pan-drug resistant organisms (PDR). Statistical significance was considered at p E. coli isolates from the study and control subjects with overall prevalence of 20.9% and 8.4% respectively. The isolates were highly resistant to penicillin (ampicillin), monobactam (aztreonam), older quinolone (nalidixic acid) whereas the majority of them showed high susceptibility to aminoglycoside (streptomycin), cephalosporin (cefotaxime) and carbapenem (imipenem). None showed complete susceptibility to all the tested antibiotics. Twenty-five E. coli were identified in this MDR, eight, XDR while 5 were PDR. High numbers of drug resistant E. coli isolates were identified in the study group of which 25 were MDR, 8 XDR while 5 were PDR isolates. High prevalence of UTI and drug resistant isolates occur in diabetic patients with hyperglycemic condition.展开更多
Urinary tract infections (UTIs) are common infections caused by normal skin or rectum bacteria that get into the urethra and infect the urinary tract. Although the infection can affect various parts of the tract, blad...Urinary tract infections (UTIs) are common infections caused by normal skin or rectum bacteria that get into the urethra and infect the urinary tract. Although the infection can affect various parts of the tract, bladder infections are the most prevalent kind. Uropathogenic Escherichia Coli (UPEC) is the most common pathogen associated with UTI development. Therefore, inhibiting the UPEC protein target (PDB ID: 8BVD) appears to be a promising therapeutic strategy. Therefore, in this study, molecular docking and dynamics were conducted to examine the antibacterial activity of Aloe barbadensis miller against UPEC bacteria. The Aloe barbadensis miller natural compounds licochalcone A, palmidin B and palmidin C were downloaded from PubChem with amoxicillin, which was used as a control drug and studied against the target molecule. The potential parameters examined were the docking scores, absorption, distribution, metabolism, excretion, toxicity (ADMET), bioavailability, root mean square deviation (RMSD), root mean square fluctuation (RMSF), hydrogen bonding, radius of gyration, and potential energy of the system. Docking scores showed that all ligands demonstrated an admirable candidature as an inhibitor to 8BVD molecule, and the score hierarchy is licochalcone A (-6.4 kcal/mol), palmidin C (-6.1 kcal/mol), palmidin B (-6.0 kcal/mol), and amoxicillin (-5.9 kcal/mol). All ligands appeared to have good drug-like properties and oral bioavailability. Molecular dynamic studies showed that all ligands exhibited an excellent nominee as inhibitors in their vicinity at 20 ns. However, there is a relatively high fluctuation of palmidin B compared with other compounds, which seems to be more stable. This work suggests that the selected phytoconstituents could be used as inhibitors of the 8BVD protein in the fight against UTIs. However, further investigation on the clinical and experimental validation of UTI treatment’s specific mechanisms and effects is still welcomed.展开更多
Background: Colibacillosis caused by enterotoxigenic Escherichia coil (E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varyin...Background: Colibacillosis caused by enterotoxigenic Escherichia coil (E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varying degrees of resistance to different antibiotics. Therefore the use of probiotics is becoming accepted as an alternative to antibiotics. In this study, we evaluated the effects of Clostfidium butyricum (C. butyficum) on growth performance, immune response, intestinal barrier function, and digestive enzyme activity in broiler chickens challenged with Eschefichia coli (E. coil) K88. Methods: The chickens were randomly divided into four treatment groups for 28 days. Negative control treatment (NC) consisted of birds fed a basal diet without E. coil K88 challenge and positive control treatment (PC) consisted of birds fed a basal diet and challenged with E. coil K88. C. buO/ricum probiotic treatment (CB) consisted of birds fed a diet containing 2 x 107 cfu C. buO/ricum/kg of diet and challenged with E. coil K88. Colistin sulfate antibiotic treatment (CS) consisted of birds fed a diet containing 20 mg colistin sulfate/kg of diet and challenged with E. coil K88. Results: The body weight (BW) and average day gain (ADG) in the broilers of CB group were higher (P 〈 0.05) than the broilers in the PC group overall except the ADG in the 14-21 d post-challenge. The birds in CB treatment had higher (P 〈 0.05) concentration of tumor necrosis factor-a (TNF-a) at 3 and 7 d post-challenge, and higher (P 〈 0.05) concentration of interleukin-4 (IL-4) at 14 d post-challenge than those in the PC treatment group. The concentration of serum endotoxin in CB birds was lower (P 〈 0.05) at 21 d post-challenge, and the concentrations of serum diamine oxidase in CB birds were lower (P 〈 0.05) at 14 and 21 d post-challenge than in PC birds. Birds in CB treatment group had higher (P 〈 0.05) jejunum villi height than those in PC, NC, or CS treatment at 7, 14, and 21 d post-challenge. In comparison to PC birds, the CB birds had lower (P 〈 0.05) jejunum crypt depth during the whole experiment. The birds in CB or CS treatment group had higher (P 〈 0.05) activities of amylase and protease at 3, 7, and 14 d post-challenge, and higher (P 〈 0.05) activity of lipase at 3, 7 d post-challenge than PC birds.展开更多
Objective:To screen for Escherichia coli(E.coli)resistant to tetracycline,followed by identification of tet efflux genes by polymerase chain reaction(PCR).In addition,detection of tetracycline residues in chicken live...Objective:To screen for Escherichia coli(E.coli)resistant to tetracycline,followed by identification of tet efflux genes by polymerase chain reaction(PCR).In addition,detection of tetracycline residues in chicken livers and kidneys were conducted using high performance liquid chromatography-tandem quadrupole mass spectrometry(HPLC-MS-MS).Methods:Strains of E.coli were isolated from samples of chicken colon and screened for tetracycline resistance.Tetracycline genes conferring resistance(Tc^r)were detected by polymerase chain reaction(PCR).Most of the isolates were resistant to tetracycline(97.9%).Results:PCR analysis indicated that Tc^r E.coli R-plasmids contained tet(A),tet(B)and a combination of both efflux genes.None of the isolates contained other efflux tet genes tet(C,D,E and Y).High performance liquid chromatography-tandem quadrupole mass spectrometry(HPLC-MS-MS),a sensitive technique,was used to detect residues of chlortetracycline(CTC),oxytetracyeline(OTC),doxveycline(DC)in chicken livers and kidneys.The samples containing tetracycline residues were at 0.13-0.65pg/μL levels.Conclusions:Tetracycline and other antibiotics are commonly used in the poultry and meat production industry for prevention of microbial infections.Multiple antibiotic resistant bacteria in Oman have increased to alarming levels,threatening public health,domestic and may have adverse effect on environment.展开更多
Objective: To investigate the occurrence of resistance genes among Escherichia coli(E. coli) and Salmonella subsp. isolated in chicken food chains in Phnom Penh, 2012–2013.Methods: Six hundred eighty two E. coli and ...Objective: To investigate the occurrence of resistance genes among Escherichia coli(E. coli) and Salmonella subsp. isolated in chicken food chains in Phnom Penh, 2012–2013.Methods: Six hundred eighty two E. coli and 181 Salmonella Albany, Corvallis, and Kentucky strains were examined for susceptibilities to eight antimicrobials and following resistance genes were identified by PCR: blaTem, Str A, aad A, sul1, sul2, gyr A, Tet(A), and Tet(B).Results: E. coli presented high resistances to tetracycline, amoxicillin, and sulfamethoxazole(63.1%–76.1%). Salmonella Albany and Salmonella Kentucky traduced high resistance percentages to amoxicillin, tetracycline, sulfamethoxazole, and nalidixic acid(84.6%–100%). Among amoxicillin-resistant isolates, blaTemgenes were observed for 62% of E. coli isolates and 20% of 65 Salmonella Kentucky. The Str A gene was prevalent in 36% of 331 aminoglycoside-resistant E. coli and 90% of 40 aminoglycoside-resistant Salmonella Corvallis. The sul2 gene was predominant among sulfamethoxazole-resistant isolates, for 56% of 431 E. coli and 53% of 66 Salmonella Corvallis; the sul1 gene was observed in 54% of Salmonella Albany. The Tet(A) resistance gene was prevalent in E.coli(86%), Salmonella Corvallis(82%), Salmonella Kentucky(84%). High percentages of gyr A genes observed among nalidixic-acid resistant E. coli(91%), Salmonella Albany(92%), Salmonella Corvallis(75%) and Salmonella Kentucky(85%).Conclusions: Important occurrences of resistance gene were observed among E. coli and Salmonella in chicken food chains in Cambodia.展开更多
Various virulence-associated genes or pathogenicity island are responsible for determining the pathogenicity of Escherichia coli strains. However, the correlation of the number and combination patterns of virulence-as...Various virulence-associated genes or pathogenicity island are responsible for determining the pathogenicity of Escherichia coli strains. However, the correlation of the number and combination patterns of virulence-associated genes in Escherichia coli strains with their pathogenicity remains largely unknown. In this work, 581 chicken Escherichia coli strains were isolated from 1045 liver samples of dead chickens from 50 chicken farms at four provinces in China during 2007-2012. Based on the pathogenic test of SPF chickens, 320 chickens pathogenic Escherichia coli isolates were identified as highly (n = 193), intermediate (n = 98) and low pathogenic (n = 29) strains, respectively. Furthermore, the number of virulence genes in the 320 chicken pathogenic and 50 non-pathogenic Escherichia coli strains was examined. Our results reveal that thirteen virulence genes in Escherichia coli strains were detected, and all strains carried at least two or more than two virulence-associated genes. This study also suggests that highly pathogenic E. coli strains simultaneously carried at least 8 to13 virulence genes while intermediate pathogenic strains carried at least 5 to 8 virulence genes. The number of virulence-associated genes detected in highly pathogenic strains showed there were more significant differences than that in low pathogenic strains (P irp2, fyuA, and colV in high pathogenic strains was significantly higher than that in low and non-pathogenic strains (P irp2, fyuA, iucA, iucD, iutA, papC, iss, tsh, and colV were more often detected in highly and intermediate pathogenic E. coli strains. Taken together, our results provide evidences demonstrating that the pathogenicity of Escherichia coli strains is closely associated with the number and combination patterns of virulence-associated genes.展开更多
Colibacillosis refers to any localized or systemic infection caused entirely or partly by avian pathogenic Escherichia coli (APEC). Colibacillosis in mammals is most often a primary enteric or urinary tract disease, w...Colibacillosis refers to any localized or systemic infection caused entirely or partly by avian pathogenic Escherichia coli (APEC). Colibacillosis in mammals is most often a primary enteric or urinary tract disease, whereas colibacillosis in poultry is typically a localized or systemic disease occurring secondarily when host defenses have been impaired or overwhelmed by virulent E. coli strains. The purpose of this study was to investigate the antimicrobial drug resistance pattern of Escherichia coli isolated from broiler chickens farms with colibacillosis infection. Dead birds from commercial broiler chicken farms showing signs of colibacillosis were necropsied and swab samples were collected from internal organs and blood aseptically for the isolation of Escherichia coli. Pure colonies of the bacteria were isolated on solid media and the isolates were identified as E. coli based on morphological and biochemical characteristics. For determination of susceptibility to antibacterial agents, the disc diffusion method on Muller-Hinton agar was used. The following antimicrobial agents were tested: gentamycin, oxytetracyline, colistin, ciprofloxacin, doxycycline, nalidixic acid, co-trimoxazole (trimethoprim-sulfamethoxazole), norefloxacin, lincospectin and cefuroxime. The drug resistance patterns of the organisms were determined as a percentage and reported at three levels: susceptible, intermediate and resistant. All the isolates of Escherichia coli showed resistance to several antibiotics and a pattern of multiple drug resistance was observed. The highest rate of resistance was observed against nalidixic acid (100%) and the least rate of resistance was observed against gentamycin (17%). According to the results of this research care must be taken to avoid secondary infection (colibacillosis) in chicken farms and also avoid in careless antimicrobial consumption in food animals including chickens.展开更多
We examined 50 Escherichia coli (E. coli) strains isolated from broiler chickens between January 2013 to March 2014 in order to evaluate the epidemiological prevalence of avian pathogenic E. coli (APEC) in Jordan by m...We examined 50 Escherichia coli (E. coli) strains isolated from broiler chickens between January 2013 to March 2014 in order to evaluate the epidemiological prevalence of avian pathogenic E. coli (APEC) in Jordan by multiplex PCR and random amplification of polymorphic DNA (RAPD) tests. The multiplex polymerase chain reaction (PCR) which was used as tentative criteria of APEC targets 8 virulence associated genes;enteroaggregative toxin (astA), Type 1 fimbria adhesion (fimH), iron-repressible protein (irp2), P fimbriae (papC), aerobactin (iucD), temperature-sensitive hemagglutinin (tsh), vacuolating autotransporter toxin (vat), and colicin V plasmid operon (cva/cvi) genes. The number of detected genes could be used as a reliable index of their virulence. E. coli strains already typed as an APEC always harbor 5 to 8 genes, but non-APEC strains harbor less than 4 genes. Assuming the criteria of an APEC is possession of 5 or more virulence associated genes;we found that all 50 E. coli strains were classified as APEC strains. The RAPD analysis showed that the E. coli strains could be grouped into 35 of RAPD types by using these two different RAPD primer sets, RAPD analysis primer 4 5'AAGAGCCCGT5', and RAPD analysis primer 6 5'CCCGTCAGCA3'. The current study confirmed the endemic nature of APEC in broiler flocks in Jordan. It is essential that the biosecurity on poultry farms should be improved to prevent the introduction and dissemination of APEC and other agents. Furthermore, farmers need to be educated about the signs, lesions, and the importance of this agent.展开更多
[ Objective] This study aimed to explore the presence of type I pill (fimC gene) and P pill (papC gene) and identify the serotype of pathogenic E. coli isolated from chickens in the Jidong Area. [ Method] Type I p...[ Objective] This study aimed to explore the presence of type I pill (fimC gene) and P pill (papC gene) and identify the serotype of pathogenic E. coli isolated from chickens in the Jidong Area. [ Method] Type I pill (fimC gene) and P pill (papC gene) were detected by PCR. The serotype was identified by con- ventional agglutination test. [ Result ] The results showed that 100% of chicken-derived E. coil strains expressed type I pill (fimC gene) ; 39.1% (9/23) of chick- en-derived E. coli strains expressed P pill (papC gene). In addition, 23 isolates of chicken-derived E. coil were assigned to 14 O serotypes, including O78, O93, O 45, O101, O38, O88, O24, O1, O163, O53, O15, O87, O34 and O29, among which O78 was the dominant serotype that accounted for 42.8% (6/14) of the total strain number. [ Conclusion] Chicken-derived E. coli strains in the Jidong Area belonged to 14 serotypes, and 078 was the dominant serotype; 83.3% of 078 serotvDe E. coli strains expressed both tvDe I Dill and P Dill.展开更多
Background:This study was conducted to investigate the effects of each phytogenic feed additive(PFA;PFA1,bitter citrus extract;PFA2,a microencapsulated blend of thymol and carvacrol;PFA3,a mixture of bitter citrus ext...Background:This study was conducted to investigate the effects of each phytogenic feed additive(PFA;PFA1,bitter citrus extract;PFA2,a microencapsulated blend of thymol and carvacrol;PFA3,a mixture of bitter citrus extract,thymol,and carvacrol;PFA4,a premixture of grape seed,grape marc extract,green tea,and hops;PFA5,fenugreek seed powder)on the growth performance,nutrient digestibility,intestinal morphology,and immune response in weaned pigs infected with Escherichia coli(E.coli).Results:A total of 634-week-old weaned pigs were placed in individual metabolic cages and assigned to seven treatment groups.The seven treatments were as follows:1)NC;basal diet without E.coli challenge,2)PC;basal diet with E.coli challenge,3)T1;PC+0.04%PFA1,4)T2;PC+0.01%PFA2,5)T3;PC+0.10%PFA3,6)T4;PC+0.04%PFA4,7)T5;PC+0.10%PFA5.The experiments lasted in 21 d,including 7 d before and 14 d after the first E.coli challenge.In the E.coli challenge treatments,all pigs were orally inoculated by dividing a total of 10 mL of E.coli F18 for 3 consecutive days.The PFA-added groups significantly increased(P<0.05)average daily gain and feed efficiency and decreased(P<0.05)the fecal score at d 0 to 14 post-inoculation(PI).Tumor necrosis factorαwas significantly lower(P<0.05)in the PFA-added groups except for T1 in d 14 PI compared to the PC treatment.The T3 had a higher(P<0.05)immunoglobulin G and immunoglobulin A concentration compared to the PC treatment at d 7 PI.Also,T3 showed significantly higher(P<0.05)villus height:crypt depth and claudin 1 expression in ileal mucosa,and significantly downregulated(P<0.05)the expression of calprotectin compared to the PC treatment.Conclusions:Supplementation of PFA in weaned pigs challenged with E.coli alleviated the negative effects of E.coli and improved growth performance.Among them,the mixed additive of bitter citrus extract,thymol,and carvacrol showed the most effective results,improving immune response,intestinal morphology,and expression of tight junctions.展开更多
Background: Escherichia coli are ubiquitous bacteria colonising both humans and animals. Extended spectrum β-lactamase-producing E. coli has been selected as a suitable indicator for the monitoring and surveillance o...Background: Escherichia coli are ubiquitous bacteria colonising both humans and animals. Extended spectrum β-lactamase-producing E. coli has been selected as a suitable indicator for the monitoring and surveillance of antimicrobial resistance. Death due to resistant bacteria is continuously rising in Cameroon, but the contribution of the aviary sector is not well studied. Therefore, this study aimed to investigate the resistance profile of extended spectrum beta-lactamases-producing Escherichia coli strains, isolated from faeces of broiler chickens in Yaoundé, capital city of Cameroon. Methods: A cross-sectional descriptive study was carried out from February to June 2020. Escherichia coli were isolated from samples of broilers in poultry farms in Yaoundé and submitted to the extended spectrum β-lactamase screening. The logistic regression was used to assess the statistical association of a significance threshold p-value of 0.05. Results: Out of 385 faecal samples collected in broiler farms, 114 Escherichia coli isolates were obtained out of which 30 (26.32%) were Extended Spectrum Beta-Lactamases-producing Escherichia coli. These isolates revealed high resistance to all antibiotic families. Poor storage conditions for feeds and the proximity to latrines, the troughs on the ground, the lack of foot bath and uniforms, the inadequate treatment of faeces, the poor usage of preventive antibiotics and the lack of water treatment have been identified as risk factors to faecal carriage of ESBL-producing Escherichia coli. Conclusion: This work reveals the emergence of Extended Spectrum Beta-Lactamases-producing Escherichia coli in poultry farms in Yaoundé and the failure in the biosecurity system. As such, the awareness of poultry breeders on the respect of biosecurity measures may be an effective tool to tackle antimicrobial resistance, specifically in livestock industries using a One Health approach.展开更多
To characterize extended-spectrum beta-lactamase (ESBL) and extra-intestinal pathogenic Escherichia coli (ExPEC) associated virulence genes in E. coli isolates from chickens and humans in Trinidad and Tobago. This cro...To characterize extended-spectrum beta-lactamase (ESBL) and extra-intestinal pathogenic Escherichia coli (ExPEC) associated virulence genes in E. coli isolates from chickens and humans in Trinidad and Tobago. This cross sectional study was conducted over a three-month period. A total of 471 E. coli isolates;160 from humans treated at a regional tertiary hospital and 311 from chicken caecal samples from “pluck shops” in Trinidad & Tobago were identified using both conventional and molecular microbiological methods. Phenotypic confirmation of ESBL producing E. coli isolates from humans was by Microscan system (Siemens, USA) while the double disk diffusion method was used for the chicken isolates. Polymerase chain reaction (PCR) analysis was used to determine the ESBL and ExPEC-associated virulence genes in representative human isolates and all chicken isolates. From the 311 chicken E. coli isolates, 49.2% (153/311) produced ESBL, while 56.3% (90/160) from humans were ESBL positive. All human and chicken ESBL isolates were 100% susceptible to carbapenems and aminoglycosides antimicrobials. PCR detected 21.1% bla<sub>CTX-M</sub>, 13.3% bla<sub>TEM</sub> and 7.8% bla<sub>SHV</sub> genes among E coli isolates from humans compared to 0.6% bla<sub>CTX-M</sub> and 48.6% bla<sub>TEM</sub> genes in chickens. PCR analysis revealed diverse virulence profiles among the isolates. There was a high occurrence rate of ExPEC-asso- ciated virulence genes in E. coli isolates from both humans and chickens. However, the CTX-M-1 genes were most predominant in humans while TEM occurred in chic- ken isolates. The diverse ESBL and virulence associated gene profiles encountered in E. coli isolates from humans and chickens on the surface depicts no similarity or relationships despite occurrence in both cohort groups. Therefore E. coli strains from chickens and humans require further investigation to determine their clonal relatedness or transmission in the country.展开更多
Context: Gastroenteritis remains an infectious disease with high morbidity and mortality particularly in low incomes countries, where the capacity to search all etiological agents, especially pathogenic Escherichia co...Context: Gastroenteritis remains an infectious disease with high morbidity and mortality particularly in low incomes countries, where the capacity to search all etiological agents, especially pathogenic Escherichia coli, is very limited. We investigated the contribution of pathogenic Escherichia coli and their antibiotic resistance profiles in cases of gastroenteritis. Methods: A cross-sectional study was carried out on human stool samples from October 2021 to June 2022 at Laquintinie Hospital. Samples were received from patients of all age groups and screened for bacteriological and parasitological identification by microscopy, bacterial culture, biochemical identification, and antimicrobial susceptibility tests. Results: A total of 296 patients with gastroenteritis complaints, were enrolled in the study with ages ranging from 5 months to 90 years old (Median = 35.5;SD = 20.8). Among the samples analyzed, 1.7% (n = 5/296) were positive for parasites and 27% (n = 80/296) were positive for bacterial pathogens. Parasites were found in mono parasitism, mainly Entamoeba histolytica (60%;n = 3/5), followed by Trichomonas intestinalis (20%;n = 1/5), and Giardia intestinalis (20%;n = 1/5). Three species of bacterial pathogens were identified with no co-infection: diarrheic Escherichia coli (DEC), Salmonella sp, and Shigella sp with respective proportions of 90% (n = 72/80), 6.3% (n = 5/80), and 3.7% (n = 3/80). For antibiotic resistance profiles (ARPs) of the 72 isolates of DEC, high levels of resistance were observed globally with amoxicillin (93.1%;n = 67/72), followed by ciprofloxacin (75%;n = 54/72), and to trimethoprim + sulfamethazole (73.6%;n = 53/72). In contrast, DEC showed low resistance rates with nitrofurans (6.9%;n = 5/72) and imipenem (2.8%;n = 2/72). The strains had 56 distinct ARPs, of which 88.9% (n = 64/72) were MDR. Salmonella sp and Shigella sp showed high levels of resistance to amoxicillin and trimethoprim + sulfamethazole. Conclusion: These results emphasize the need to consider DEC as the main cause of consultation in cases of gastroenteritis and reiterate the urgent need to rationalize antibiotic use in Cameroon.展开更多
文摘Resistant bacteria can be transmitted to humans through feces or contaminated meat from local chickens. Bacterial strains were isolated from the intestinal contents of 400 local chicken samples from various sales sites. These strains were then characterized using bacteriological and biochemical methods to identify resistant strains. In a study conducted in Ouagadougou, we systematically collected chicken fecal samples from 20 locations across the city, followed by isolation and identification of Salmonella spp. using specific enrichment and culture methods, as well as Escherichia coli. Bacterial strains were characterized using antibiotic resistance profiles were determined through agar diffusion tests, revealing sensitivity or resistance to a range of antibiotics based on established scientific criteria. The results showed that out of the 400 samples collected, 81.25% and 63.5% were contaminated by Escherichia coli and Salmonella spp., respectively. Among these, 86.15% of identified Escherichia coli and 50.78% of Salmonella spp. displayed resistance to at least one tested antibiotic. Among 280 Escherichia coli isolates identified resistant to at least one antibiotic, 31.07% were resistant to cefotaxime (CTX), 20.35% to ceftazidime (CAZ), 21.07% to ceftriaxone (CTR), 75% to amoxicillin clavulanic acid (AMC), 23.57% aztreoname (ATM) and 27.14% were resistant to imipenem (IMP). In the case of the 129 Salmonella spp. isolates resistant to at least one tested antibiotic, 34.88% were resistant to CTX;41.08% to CAZ;35.65% to CTR, 92% to AMC, 39.53% to ATM and finally 47.28% were resistant to IMP. Our study revealed high prevalence of resistance in bacterial strains isolated from local chickens sold outdoors in Ouagadougou. These findings raise significant public health concerns, due to the possible transmission of these resistant strains to humans through the consumption of contaminated meat, thus complicating the treatment of bacterial infections.
基金supported by National Natural Science Foundation of China(31972021)R&D Projects in Key Areas of Guangdong Province(2019B020212003)+4 种基金the Science and Technology Program of Guangzhou,China(202206010177)Guangdong key research and development program(2021B0202060001)Foshan and agricultural academy cooperation projectGuangdong Modern Agriculture project(2022KJ117)Aquatic Products Center Project of GAAS。
文摘Escherichia coli O157:H7 is one of the major foodborne pathogenic bacterial that cause infectious diseases in humans.The previous found that a combination of kojic acid and tea polyphenols exhibited better activity against E.coli O157:H7 than using either alone.This study aimed to explore responses underlying the antibacterial mechanisms of kojic acid and tea polyphenols from the gene level.The functional enrichment analysis by comparing kojic acid and tea polyphenols individually or synergistically against E.coli O157:H7 found that acid resistance systems in kojic acid were activated,and the cell membrane and genomic DNA were destructed in the cells,resulting in“oxygen starvation”.The oxidative stress response triggered by tea polyphenols inhibited both sulfur uptake and the synthesis of ATP,which affected the bacteria's life metabolic process.Interestingly,we found that kojic acid combined with tea polyphenols hindered the uptake of iron that played an essential role in the synthesis of DNA,respiration,tricarboxylic acid cycle.The results suggested that the iron uptake pathways may represent a novel approach for kojic acid and tea polyphenols synergistically against E.coli O157:H7 and provided a theoretical basis for bacterial pathogen control in the food industry.
基金the National Key Research and Development Program of China(2018YFE0192600)the Shanghai Agriculture Applied Technology Development Program,China(T20200104)+1 种基金the Fundamental Research Funds for the Central Universities,China(2020JB05)the Agricultural Science and Technology Innovation Program of Chinese Academy of Agricultural Sciences(CAAS-ZDRW202203).
文摘An extensively drug-resistant(XDR)Escherichia coli strain 258E was isolated from an anal swab sample of a chicken farm of Anhui province in China.Genomic analyses indicated that the strain 258E harbors an incompatibility group N(IncN)plasmid pEC258-3,which co-produces bla_(CTX-M-3),bla_(KPC-2),bla_(TEM-1B),qnrS1,aac(6')-Ib-cr,dfrA14,arr-3,and aac(6')-Ib3.Multiple genome arrangement analyses indicated that pEC258-3 is highly homologous with pCRKP-1-KPC discovered in Klebsiella pneumoniae from a patient.Furthermore,conjugation experiments proved that plasmid pEC258-3 can be transferred horizontally and may pose a significant potential threat in animals,community and hospital settings.
基金Supported by the French patient’s association against cancer(ligue contre le cancer),No.00001005238the French government IDEXISITE initiative,No.16-IDEX-0001-CAP 20-25+2 种基金CPER(Nex-N-Mob)the Auvergne-Rhône-Alpes region(“Thématiquesémergentes”),No.AV0004111the Ministère de l'Enseignement supérieur,de la Recherche et de l'Innovation,INSERM,University of Clermont Auvergne[UMR1071,UMR1107],INRAE[USC-1382].
文摘BACKGROUND The association between the intestinal microbiota and psychiatric disorders is becoming increasingly apparent.The gut microbiota contributes to colorectal carcinogenesis(CRC),as demonstrated with colibactin-producing Escherichia coli(CoPEC).AIM To evaluate the association between CoPEC prevalence and anxiety-and depressive-like behaviors with both preclinical and clinical approaches.METHODS Patients followed after a CRC surgery and for whom the prevalence of CoPEC has been investigated underwent a psychiatric interview.Results were compared according to the CoPEC colonization.In parallel C57BL6/J wild type mice and mice with a CRC susceptibility were chronically infected with a CoPEC strain.Their behavior was assessed using the Elevated Plus Maze test,the Forced Swimming Test and the Behavior recognition system PhenoTyper®.RESULTS In a limited cohort,all patients with CoPEC colonization presented with psychiatric disorders several years before cancer diagnosis,whereas only one patient(17%)without CoPEC did.This result was confirmed in C57BL6/J wildtype mice and in a CRC susceptibility mouse model(adenomatous polyposis colimultiple intestinal neoplasia/+).Mice exhibited a significant increase in anxiety-and depressive-like behaviors after chronic infection with a CoPEC strain.CONCLUSION This finding provides the first evidence that CoPEC infection can induce microbiota-gut-brain axis disturbances in addition to its procarcinogenic properties.
基金supported by the National Natural Science Foundation of China Young Scholars Project(31902242)the Agricultural Science and Technology Innovation Program(ASTIP)of Chinese Academy of Agricultural Sciences(2017–2020)。
文摘Avian pathogenic Escherichia coli(APEC)belonging to extraintestinal pathogenic E.coli(ExPEC)can cause severe infections in extraintestinal tissues in birds and humans,such as the lungs and blood.MprA(microcin production regulation,locus A,herein renamed AbsR,a blood survival regulator),a member of the MarR(multiple antibiotic resistance regulator)transcriptional regulator family,governs the expression of capsule biosynthetic genes in human ExPEC and represents a promising druggable target for antimicrobials.However,a deep understanding of the AbsR regulatory mechanism as well as its regulon is lacking.In this study,we present a systems-level analysis of the APEC AbsR regulon using ChIP-Seq(chromatin immunoprecipitation sequencing)and RNA-Seq(RNA sequencing)methods.We found that AbsR directly regulates 99 genes and indirectly regulates 667 genes.Furthermore,we showed that:1)AbsR contributes to antiphagocytotic effects by macrophages and virulence in a mouse model for systemic infection by directly activating the capsular gene cluster;2)AbsR positively impacts biofilm formation via direct regulation of the T2SS(type II secretion system)but plays a marginal role in virulence;and 3)AbsR directly upregulates the acid tolerance signaling system EvgAS to withstand acid stress but is dispensable in ExPEC virulence.Finally,our data indicate that the role of AbsR in virulence gene regulation is relatively conserved in ExPEC strains.Altogether,this study provides a comprehensive analysis of the AbsR regulon and regulatory mechanism,and our data suggest that AbsR likely influences virulence primarily through the control of capsule production.Interestingly,we found that AbsR severely represses the expression of the type I-F CRISPR(clustered regularly interspaced short palindromic repeats)-Cas(CRISPR associated)systems,which could have implications in CRISPR biology and application.
文摘Escherichia coli is the commonest bacterial uropathogen of UTIs, the commonest infections in immunocompromised diabetic patients. Better understanding of their main resistance mechanisms to commonly used antibacterial agents will help to reduce the burden of this infection. The prevalence of drug resistant uropathogenic Escherichia coli isolates from immunocompromised diabetic patients attending selected health facilities in Benue State was investigated. Two hundred and ninety-six midstream urine samples were collected for both study and control diabetic patients. Bacterial isolation was done using semi-quantitative method. Drug resistant Escherichia coli were identified as multidrug resistant (MDR), extensive drug resistant (XDR) and pan-drug resistant organisms (PDR). Statistical significance was considered at p E. coli isolates from the study and control subjects with overall prevalence of 20.9% and 8.4% respectively. The isolates were highly resistant to penicillin (ampicillin), monobactam (aztreonam), older quinolone (nalidixic acid) whereas the majority of them showed high susceptibility to aminoglycoside (streptomycin), cephalosporin (cefotaxime) and carbapenem (imipenem). None showed complete susceptibility to all the tested antibiotics. Twenty-five E. coli were identified in this MDR, eight, XDR while 5 were PDR. High numbers of drug resistant E. coli isolates were identified in the study group of which 25 were MDR, 8 XDR while 5 were PDR isolates. High prevalence of UTI and drug resistant isolates occur in diabetic patients with hyperglycemic condition.
文摘Urinary tract infections (UTIs) are common infections caused by normal skin or rectum bacteria that get into the urethra and infect the urinary tract. Although the infection can affect various parts of the tract, bladder infections are the most prevalent kind. Uropathogenic Escherichia Coli (UPEC) is the most common pathogen associated with UTI development. Therefore, inhibiting the UPEC protein target (PDB ID: 8BVD) appears to be a promising therapeutic strategy. Therefore, in this study, molecular docking and dynamics were conducted to examine the antibacterial activity of Aloe barbadensis miller against UPEC bacteria. The Aloe barbadensis miller natural compounds licochalcone A, palmidin B and palmidin C were downloaded from PubChem with amoxicillin, which was used as a control drug and studied against the target molecule. The potential parameters examined were the docking scores, absorption, distribution, metabolism, excretion, toxicity (ADMET), bioavailability, root mean square deviation (RMSD), root mean square fluctuation (RMSF), hydrogen bonding, radius of gyration, and potential energy of the system. Docking scores showed that all ligands demonstrated an admirable candidature as an inhibitor to 8BVD molecule, and the score hierarchy is licochalcone A (-6.4 kcal/mol), palmidin C (-6.1 kcal/mol), palmidin B (-6.0 kcal/mol), and amoxicillin (-5.9 kcal/mol). All ligands appeared to have good drug-like properties and oral bioavailability. Molecular dynamic studies showed that all ligands exhibited an excellent nominee as inhibitors in their vicinity at 20 ns. However, there is a relatively high fluctuation of palmidin B compared with other compounds, which seems to be more stable. This work suggests that the selected phytoconstituents could be used as inhibitors of the 8BVD protein in the fight against UTIs. However, further investigation on the clinical and experimental validation of UTI treatment’s specific mechanisms and effects is still welcomed.
基金supported by the International Cooperation Project of Zhejiang Province(No.2012C14031)Innovative Research Team Program of Zhejiang Province(No.2011R50025)
文摘Background: Colibacillosis caused by enterotoxigenic Escherichia coil (E. coil} results in economic losses in the poultry industry. Antibiotics are usually used to control colibacillosis, however, E. coli has varying degrees of resistance to different antibiotics. Therefore the use of probiotics is becoming accepted as an alternative to antibiotics. In this study, we evaluated the effects of Clostfidium butyricum (C. butyficum) on growth performance, immune response, intestinal barrier function, and digestive enzyme activity in broiler chickens challenged with Eschefichia coli (E. coil) K88. Methods: The chickens were randomly divided into four treatment groups for 28 days. Negative control treatment (NC) consisted of birds fed a basal diet without E. coil K88 challenge and positive control treatment (PC) consisted of birds fed a basal diet and challenged with E. coil K88. C. buO/ricum probiotic treatment (CB) consisted of birds fed a diet containing 2 x 107 cfu C. buO/ricum/kg of diet and challenged with E. coil K88. Colistin sulfate antibiotic treatment (CS) consisted of birds fed a diet containing 20 mg colistin sulfate/kg of diet and challenged with E. coil K88. Results: The body weight (BW) and average day gain (ADG) in the broilers of CB group were higher (P 〈 0.05) than the broilers in the PC group overall except the ADG in the 14-21 d post-challenge. The birds in CB treatment had higher (P 〈 0.05) concentration of tumor necrosis factor-a (TNF-a) at 3 and 7 d post-challenge, and higher (P 〈 0.05) concentration of interleukin-4 (IL-4) at 14 d post-challenge than those in the PC treatment group. The concentration of serum endotoxin in CB birds was lower (P 〈 0.05) at 21 d post-challenge, and the concentrations of serum diamine oxidase in CB birds were lower (P 〈 0.05) at 14 and 21 d post-challenge than in PC birds. Birds in CB treatment group had higher (P 〈 0.05) jejunum villi height than those in PC, NC, or CS treatment at 7, 14, and 21 d post-challenge. In comparison to PC birds, the CB birds had lower (P 〈 0.05) jejunum crypt depth during the whole experiment. The birds in CB or CS treatment group had higher (P 〈 0.05) activities of amylase and protease at 3, 7, and 14 d post-challenge, and higher (P 〈 0.05) activity of lipase at 3, 7 d post-challenge than PC birds.
文摘Objective:To screen for Escherichia coli(E.coli)resistant to tetracycline,followed by identification of tet efflux genes by polymerase chain reaction(PCR).In addition,detection of tetracycline residues in chicken livers and kidneys were conducted using high performance liquid chromatography-tandem quadrupole mass spectrometry(HPLC-MS-MS).Methods:Strains of E.coli were isolated from samples of chicken colon and screened for tetracycline resistance.Tetracycline genes conferring resistance(Tc^r)were detected by polymerase chain reaction(PCR).Most of the isolates were resistant to tetracycline(97.9%).Results:PCR analysis indicated that Tc^r E.coli R-plasmids contained tet(A),tet(B)and a combination of both efflux genes.None of the isolates contained other efflux tet genes tet(C,D,E and Y).High performance liquid chromatography-tandem quadrupole mass spectrometry(HPLC-MS-MS),a sensitive technique,was used to detect residues of chlortetracycline(CTC),oxytetracyeline(OTC),doxveycline(DC)in chicken livers and kidneys.The samples containing tetracycline residues were at 0.13-0.65pg/μL levels.Conclusions:Tetracycline and other antibiotics are commonly used in the poultry and meat production industry for prevention of microbial infections.Multiple antibiotic resistant bacteria in Oman have increased to alarming levels,threatening public health,domestic and may have adverse effect on environment.
基金the World Health Organization under AGISAR grant agreement 2012/2469940 on 03 July 2012the Food and Agriculture Organization of the United Nation agreement Lo A/RP/CMB/2011/AGNDC/ PO280544 on 07 December 2011
文摘Objective: To investigate the occurrence of resistance genes among Escherichia coli(E. coli) and Salmonella subsp. isolated in chicken food chains in Phnom Penh, 2012–2013.Methods: Six hundred eighty two E. coli and 181 Salmonella Albany, Corvallis, and Kentucky strains were examined for susceptibilities to eight antimicrobials and following resistance genes were identified by PCR: blaTem, Str A, aad A, sul1, sul2, gyr A, Tet(A), and Tet(B).Results: E. coli presented high resistances to tetracycline, amoxicillin, and sulfamethoxazole(63.1%–76.1%). Salmonella Albany and Salmonella Kentucky traduced high resistance percentages to amoxicillin, tetracycline, sulfamethoxazole, and nalidixic acid(84.6%–100%). Among amoxicillin-resistant isolates, blaTemgenes were observed for 62% of E. coli isolates and 20% of 65 Salmonella Kentucky. The Str A gene was prevalent in 36% of 331 aminoglycoside-resistant E. coli and 90% of 40 aminoglycoside-resistant Salmonella Corvallis. The sul2 gene was predominant among sulfamethoxazole-resistant isolates, for 56% of 431 E. coli and 53% of 66 Salmonella Corvallis; the sul1 gene was observed in 54% of Salmonella Albany. The Tet(A) resistance gene was prevalent in E.coli(86%), Salmonella Corvallis(82%), Salmonella Kentucky(84%). High percentages of gyr A genes observed among nalidixic-acid resistant E. coli(91%), Salmonella Albany(92%), Salmonella Corvallis(75%) and Salmonella Kentucky(85%).Conclusions: Important occurrences of resistance gene were observed among E. coli and Salmonella in chicken food chains in Cambodia.
文摘Various virulence-associated genes or pathogenicity island are responsible for determining the pathogenicity of Escherichia coli strains. However, the correlation of the number and combination patterns of virulence-associated genes in Escherichia coli strains with their pathogenicity remains largely unknown. In this work, 581 chicken Escherichia coli strains were isolated from 1045 liver samples of dead chickens from 50 chicken farms at four provinces in China during 2007-2012. Based on the pathogenic test of SPF chickens, 320 chickens pathogenic Escherichia coli isolates were identified as highly (n = 193), intermediate (n = 98) and low pathogenic (n = 29) strains, respectively. Furthermore, the number of virulence genes in the 320 chicken pathogenic and 50 non-pathogenic Escherichia coli strains was examined. Our results reveal that thirteen virulence genes in Escherichia coli strains were detected, and all strains carried at least two or more than two virulence-associated genes. This study also suggests that highly pathogenic E. coli strains simultaneously carried at least 8 to13 virulence genes while intermediate pathogenic strains carried at least 5 to 8 virulence genes. The number of virulence-associated genes detected in highly pathogenic strains showed there were more significant differences than that in low pathogenic strains (P irp2, fyuA, and colV in high pathogenic strains was significantly higher than that in low and non-pathogenic strains (P irp2, fyuA, iucA, iucD, iutA, papC, iss, tsh, and colV were more often detected in highly and intermediate pathogenic E. coli strains. Taken together, our results provide evidences demonstrating that the pathogenicity of Escherichia coli strains is closely associated with the number and combination patterns of virulence-associated genes.
文摘Colibacillosis refers to any localized or systemic infection caused entirely or partly by avian pathogenic Escherichia coli (APEC). Colibacillosis in mammals is most often a primary enteric or urinary tract disease, whereas colibacillosis in poultry is typically a localized or systemic disease occurring secondarily when host defenses have been impaired or overwhelmed by virulent E. coli strains. The purpose of this study was to investigate the antimicrobial drug resistance pattern of Escherichia coli isolated from broiler chickens farms with colibacillosis infection. Dead birds from commercial broiler chicken farms showing signs of colibacillosis were necropsied and swab samples were collected from internal organs and blood aseptically for the isolation of Escherichia coli. Pure colonies of the bacteria were isolated on solid media and the isolates were identified as E. coli based on morphological and biochemical characteristics. For determination of susceptibility to antibacterial agents, the disc diffusion method on Muller-Hinton agar was used. The following antimicrobial agents were tested: gentamycin, oxytetracyline, colistin, ciprofloxacin, doxycycline, nalidixic acid, co-trimoxazole (trimethoprim-sulfamethoxazole), norefloxacin, lincospectin and cefuroxime. The drug resistance patterns of the organisms were determined as a percentage and reported at three levels: susceptible, intermediate and resistant. All the isolates of Escherichia coli showed resistance to several antibiotics and a pattern of multiple drug resistance was observed. The highest rate of resistance was observed against nalidixic acid (100%) and the least rate of resistance was observed against gentamycin (17%). According to the results of this research care must be taken to avoid secondary infection (colibacillosis) in chicken farms and also avoid in careless antimicrobial consumption in food animals including chickens.
文摘We examined 50 Escherichia coli (E. coli) strains isolated from broiler chickens between January 2013 to March 2014 in order to evaluate the epidemiological prevalence of avian pathogenic E. coli (APEC) in Jordan by multiplex PCR and random amplification of polymorphic DNA (RAPD) tests. The multiplex polymerase chain reaction (PCR) which was used as tentative criteria of APEC targets 8 virulence associated genes;enteroaggregative toxin (astA), Type 1 fimbria adhesion (fimH), iron-repressible protein (irp2), P fimbriae (papC), aerobactin (iucD), temperature-sensitive hemagglutinin (tsh), vacuolating autotransporter toxin (vat), and colicin V plasmid operon (cva/cvi) genes. The number of detected genes could be used as a reliable index of their virulence. E. coli strains already typed as an APEC always harbor 5 to 8 genes, but non-APEC strains harbor less than 4 genes. Assuming the criteria of an APEC is possession of 5 or more virulence associated genes;we found that all 50 E. coli strains were classified as APEC strains. The RAPD analysis showed that the E. coli strains could be grouped into 35 of RAPD types by using these two different RAPD primer sets, RAPD analysis primer 4 5'AAGAGCCCGT5', and RAPD analysis primer 6 5'CCCGTCAGCA3'. The current study confirmed the endemic nature of APEC in broiler flocks in Jordan. It is essential that the biosecurity on poultry farms should be improved to prevent the introduction and dissemination of APEC and other agents. Furthermore, farmers need to be educated about the signs, lesions, and the importance of this agent.
基金Supported by National Natural Science Foundation of China(31072136)Agricultural Science and Technology Achievement Transformation Project of the Ministry of Science and Technology of China(2012GB2A200044)Project of Shijiazhuang Municipal Science and Technology Bureau(11150093A)
文摘[ Objective] This study aimed to explore the presence of type I pill (fimC gene) and P pill (papC gene) and identify the serotype of pathogenic E. coli isolated from chickens in the Jidong Area. [ Method] Type I pill (fimC gene) and P pill (papC gene) were detected by PCR. The serotype was identified by con- ventional agglutination test. [ Result ] The results showed that 100% of chicken-derived E. coil strains expressed type I pill (fimC gene) ; 39.1% (9/23) of chick- en-derived E. coli strains expressed P pill (papC gene). In addition, 23 isolates of chicken-derived E. coil were assigned to 14 O serotypes, including O78, O93, O 45, O101, O38, O88, O24, O1, O163, O53, O15, O87, O34 and O29, among which O78 was the dominant serotype that accounted for 42.8% (6/14) of the total strain number. [ Conclusion] Chicken-derived E. coli strains in the Jidong Area belonged to 14 serotypes, and 078 was the dominant serotype; 83.3% of 078 serotvDe E. coli strains expressed both tvDe I Dill and P Dill.
基金carried out with the support of“Cooperative Research Program for Agriculture Science&Technology Development(Project No.PJ01622001)”Rural Development Administration,Korea。
文摘Background:This study was conducted to investigate the effects of each phytogenic feed additive(PFA;PFA1,bitter citrus extract;PFA2,a microencapsulated blend of thymol and carvacrol;PFA3,a mixture of bitter citrus extract,thymol,and carvacrol;PFA4,a premixture of grape seed,grape marc extract,green tea,and hops;PFA5,fenugreek seed powder)on the growth performance,nutrient digestibility,intestinal morphology,and immune response in weaned pigs infected with Escherichia coli(E.coli).Results:A total of 634-week-old weaned pigs were placed in individual metabolic cages and assigned to seven treatment groups.The seven treatments were as follows:1)NC;basal diet without E.coli challenge,2)PC;basal diet with E.coli challenge,3)T1;PC+0.04%PFA1,4)T2;PC+0.01%PFA2,5)T3;PC+0.10%PFA3,6)T4;PC+0.04%PFA4,7)T5;PC+0.10%PFA5.The experiments lasted in 21 d,including 7 d before and 14 d after the first E.coli challenge.In the E.coli challenge treatments,all pigs were orally inoculated by dividing a total of 10 mL of E.coli F18 for 3 consecutive days.The PFA-added groups significantly increased(P<0.05)average daily gain and feed efficiency and decreased(P<0.05)the fecal score at d 0 to 14 post-inoculation(PI).Tumor necrosis factorαwas significantly lower(P<0.05)in the PFA-added groups except for T1 in d 14 PI compared to the PC treatment.The T3 had a higher(P<0.05)immunoglobulin G and immunoglobulin A concentration compared to the PC treatment at d 7 PI.Also,T3 showed significantly higher(P<0.05)villus height:crypt depth and claudin 1 expression in ileal mucosa,and significantly downregulated(P<0.05)the expression of calprotectin compared to the PC treatment.Conclusions:Supplementation of PFA in weaned pigs challenged with E.coli alleviated the negative effects of E.coli and improved growth performance.Among them,the mixed additive of bitter citrus extract,thymol,and carvacrol showed the most effective results,improving immune response,intestinal morphology,and expression of tight junctions.
文摘Background: Escherichia coli are ubiquitous bacteria colonising both humans and animals. Extended spectrum β-lactamase-producing E. coli has been selected as a suitable indicator for the monitoring and surveillance of antimicrobial resistance. Death due to resistant bacteria is continuously rising in Cameroon, but the contribution of the aviary sector is not well studied. Therefore, this study aimed to investigate the resistance profile of extended spectrum beta-lactamases-producing Escherichia coli strains, isolated from faeces of broiler chickens in Yaoundé, capital city of Cameroon. Methods: A cross-sectional descriptive study was carried out from February to June 2020. Escherichia coli were isolated from samples of broilers in poultry farms in Yaoundé and submitted to the extended spectrum β-lactamase screening. The logistic regression was used to assess the statistical association of a significance threshold p-value of 0.05. Results: Out of 385 faecal samples collected in broiler farms, 114 Escherichia coli isolates were obtained out of which 30 (26.32%) were Extended Spectrum Beta-Lactamases-producing Escherichia coli. These isolates revealed high resistance to all antibiotic families. Poor storage conditions for feeds and the proximity to latrines, the troughs on the ground, the lack of foot bath and uniforms, the inadequate treatment of faeces, the poor usage of preventive antibiotics and the lack of water treatment have been identified as risk factors to faecal carriage of ESBL-producing Escherichia coli. Conclusion: This work reveals the emergence of Extended Spectrum Beta-Lactamases-producing Escherichia coli in poultry farms in Yaoundé and the failure in the biosecurity system. As such, the awareness of poultry breeders on the respect of biosecurity measures may be an effective tool to tackle antimicrobial resistance, specifically in livestock industries using a One Health approach.
文摘To characterize extended-spectrum beta-lactamase (ESBL) and extra-intestinal pathogenic Escherichia coli (ExPEC) associated virulence genes in E. coli isolates from chickens and humans in Trinidad and Tobago. This cross sectional study was conducted over a three-month period. A total of 471 E. coli isolates;160 from humans treated at a regional tertiary hospital and 311 from chicken caecal samples from “pluck shops” in Trinidad & Tobago were identified using both conventional and molecular microbiological methods. Phenotypic confirmation of ESBL producing E. coli isolates from humans was by Microscan system (Siemens, USA) while the double disk diffusion method was used for the chicken isolates. Polymerase chain reaction (PCR) analysis was used to determine the ESBL and ExPEC-associated virulence genes in representative human isolates and all chicken isolates. From the 311 chicken E. coli isolates, 49.2% (153/311) produced ESBL, while 56.3% (90/160) from humans were ESBL positive. All human and chicken ESBL isolates were 100% susceptible to carbapenems and aminoglycosides antimicrobials. PCR detected 21.1% bla<sub>CTX-M</sub>, 13.3% bla<sub>TEM</sub> and 7.8% bla<sub>SHV</sub> genes among E coli isolates from humans compared to 0.6% bla<sub>CTX-M</sub> and 48.6% bla<sub>TEM</sub> genes in chickens. PCR analysis revealed diverse virulence profiles among the isolates. There was a high occurrence rate of ExPEC-asso- ciated virulence genes in E. coli isolates from both humans and chickens. However, the CTX-M-1 genes were most predominant in humans while TEM occurred in chic- ken isolates. The diverse ESBL and virulence associated gene profiles encountered in E. coli isolates from humans and chickens on the surface depicts no similarity or relationships despite occurrence in both cohort groups. Therefore E. coli strains from chickens and humans require further investigation to determine their clonal relatedness or transmission in the country.
文摘Context: Gastroenteritis remains an infectious disease with high morbidity and mortality particularly in low incomes countries, where the capacity to search all etiological agents, especially pathogenic Escherichia coli, is very limited. We investigated the contribution of pathogenic Escherichia coli and their antibiotic resistance profiles in cases of gastroenteritis. Methods: A cross-sectional study was carried out on human stool samples from October 2021 to June 2022 at Laquintinie Hospital. Samples were received from patients of all age groups and screened for bacteriological and parasitological identification by microscopy, bacterial culture, biochemical identification, and antimicrobial susceptibility tests. Results: A total of 296 patients with gastroenteritis complaints, were enrolled in the study with ages ranging from 5 months to 90 years old (Median = 35.5;SD = 20.8). Among the samples analyzed, 1.7% (n = 5/296) were positive for parasites and 27% (n = 80/296) were positive for bacterial pathogens. Parasites were found in mono parasitism, mainly Entamoeba histolytica (60%;n = 3/5), followed by Trichomonas intestinalis (20%;n = 1/5), and Giardia intestinalis (20%;n = 1/5). Three species of bacterial pathogens were identified with no co-infection: diarrheic Escherichia coli (DEC), Salmonella sp, and Shigella sp with respective proportions of 90% (n = 72/80), 6.3% (n = 5/80), and 3.7% (n = 3/80). For antibiotic resistance profiles (ARPs) of the 72 isolates of DEC, high levels of resistance were observed globally with amoxicillin (93.1%;n = 67/72), followed by ciprofloxacin (75%;n = 54/72), and to trimethoprim + sulfamethazole (73.6%;n = 53/72). In contrast, DEC showed low resistance rates with nitrofurans (6.9%;n = 5/72) and imipenem (2.8%;n = 2/72). The strains had 56 distinct ARPs, of which 88.9% (n = 64/72) were MDR. Salmonella sp and Shigella sp showed high levels of resistance to amoxicillin and trimethoprim + sulfamethazole. Conclusion: These results emphasize the need to consider DEC as the main cause of consultation in cases of gastroenteritis and reiterate the urgent need to rationalize antibiotic use in Cameroon.