Resistance and virulence distribution in enterococci isolated from broilers reared in two farming systems

Abstract Background The impact of enterococci in human health has been growing for the last decades, mainly due to their resistance to several antimicrobial agents. Human consumption of contaminated meat, especially poultry, has been identified as a possible route of transmission. The aim of the present study was to evaluate and compare the antimicrobial resistance profiles and virulence genes of enterococci isolated from Portuguese conventional and free-range broiler farms. Results Antibiotic susceptibility testing showed high frequencies of resistance to tetracycline in both farming systems. Resistance to erythromycin and gentamicin were detected in about half of the isolates. Resistance to penicillin was the less frequently observed and no vancomycin resistant isolates were identified. The majority of the enterococcal isolates, from either farming systems, were resistant to more than one antibiotic, and no statistical associations were found, except for penicillin resistance which associated with the genetic clusters. No differences were found between farming systems regarding the prevalence of tet(M), erm(B), aac (6′)-Ie-aph (2″)-Ia and pbp5 genes, nevertheless pbp5 prevalence was associated with the different genetic clusters. Hemolytic activity was identified in 26.47% of all isolates and gelatinase activity in 50%. The gelE gene was identified in the majority of the isolates, whereas esp and agg genes were rarely detected. The cylA determinant was not detected in any of the isolates. Conclusions Overall, results suggest that similar resistance patterns and virulence genes can be found in both farming systems, though enterococci in free-range conditions should be less prone to acquire further resistance genes.

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Antimicrobial resistance and genetic characteristics of integron-carrier shigellae isolated in Hungary (1998–2008)

Journal of Medical Microbiology ◽

10.1099/jmm.0.058917-0 ◽

2013 ◽

Vol 62 (10) ◽

pp. 1545-1551 ◽

Cited By ~ 14

Author(s):

Noémi Nógrády ◽

Margit Király ◽

Klára Borbás ◽

Ákos Tóth ◽

Judit Pászti ◽

...

Keyword(s):

Virulence Genes ◽

Shigella Flexneri ◽

Variable Regions ◽

Genetic Characteristics ◽

High Incidence ◽

Class 1 ◽

Resistance Patterns ◽

Genetic Clusters ◽

Stool Samples ◽

Lactamase Gene

Antimicrobial susceptibility, integron carriage, genetic relationship and presence of some important virulence genes of the integron-carrier strains of Shigella sonnei (n = 230) and Shigella flexneri (n = 22) isolated from stool samples of patients in Hungary between 1998 and 2008 were investigated. Sixty-seven per cent (168/252) of the strains were resistant to sulfamethoxazole/trimethoprim (SxT) followed by streptomycin (S, 47 %), ampicillin (A, 32 %) and tetracycline (Tc, 28 %). Thirty-six per cent (90/252) exhibited multidrug resistance, mostly showing SSxTTc or ASSxTc, ASSxTTc resistance patterns. An S. sonnei strain of imported origin was resistant to cefotaxime and harboured a bla CTX-M-55-type extended-spectrum β-lactamase gene. Altogether 33 % of the S. sonnei (n = 75) and 14 % of the S. flexneri (n = 3) strains had either class 1 or class 2 integrons or both. The variable regions encoded aadA1 or dfrA1-aadA1 genes for the class 1 and dfrA1-sat2-aadA1 or dfrA1-sat2 genes for the class 2 integrons. Pulsed-field gel electrophoresis analysis revealed that those strains that have different integron types represented different genetic clusters. The Shiga toxin (stx1) gene was identified in one S. sonnei strain and the cdtB gene was detected in an S. flexneri strain. The results reveal the high incidence of antibiotic resistance among Shigella isolates and the presence of the stx1 gene in S. sonnei and the cdtB gene in S. flexneri. The genetic diversity of Shigella spp. isolated recently in Hungary was also demonstrated.

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Relation of Enterococcus faecalis and Enterococcus faecium Isolates from Foods and Clinical Specimens

Journal of Food Protection ◽

10.4315/0362-028x-71.10.2100 ◽

2008 ◽

Vol 71 (10) ◽

pp. 2100-2104 ◽

Cited By ~ 16

Author(s):

S. P. TEMPLER ◽

P. ROHNER ◽

A. BAUMGARTNER

Keyword(s):

Enterococcus Faecalis ◽

Enterococcus Faecium ◽

Virulence Genes ◽

Antimicrobial Agents ◽

Patient Specific ◽

Pfge Typing ◽

Resistance Patterns ◽

Small Clusters ◽

Pfge Profiles

Clinical Enterococcus faecalis (n = 65) and Enterococcus faecium (n = 12) blood isolates from three Swiss hospitals were characterized with testing for resistance to antimicrobial agents, pulsed-field gel electrophoresis (PFGE), and the occurrence of virulence factors. Phenotypic determination of resistance to antimicrobial agents resulted in 20% of E. faecalis isolates showing a triple resistance against chloramphenicol, tetracycline, erythromycin, and seven isolates (two E. faecalis and five E. faecium) exhibiting a multiresistance against five or more antimicrobials. One isolate each of E. faecalis and E. faecium showed vancomycin resistance. All isolates contained at least two of the nine tested virulence genes (agg, gelE, cyl, esp, efaAfs, efaAfm, cpd, cob, and ccf ). Phylogenetic analysis of the PFGE profiles identified several small clusters within E. faecalis isolates, one of which included isolates of all three hospitals. Fifty-six (73%) isolates occurred as unique, patient-specific clones. Several PFGE types were associated with shared features in their resistance patterns, indicating spread between and within wards. Finally, enterococci from this study and previous isolates from cheeses were examined by PFGE typing. The comparison of PFGE profiles from human and food isolates resulted in clusters of genetically strong related strains, which suggests high similarities of the enterococcal community composition of these two environments. A possible spread of the enterococcal isolates through the food supply cannot be excluded.

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Safety Evaluation of Enterocin Producer Enterococcus sp. Strains Isolated from Traditional Turkish Cheeses

Polish Journal of Microbiology ◽

10.5604/01.3001.0010.7839 ◽

2017 ◽

Vol 66 (2) ◽

pp. 223-233 ◽

Cited By ~ 6

Author(s):

Mine Avci ◽

Banu Özden Tuncer

Keyword(s):

Virulence Genes ◽

Safety Evaluation ◽

Haemolytic Activity ◽

Decarboxylase Activity ◽

Multiple Antibiotic Resistance ◽

Structural Genes ◽

Gelatinase Activity ◽

Enterococcus Spp ◽

Resistance Patterns ◽

Antibiotic Resistance Patterns

The purpose of this study was to determine the antimicrobial activity and the occurrence of bacteriocin structural genes in Enterococcus spp. isolated from different cheeses and also investigate of their some virulence factors. Enterococcus strains were isolated from 33 different cheeses. Enterococcus faecium (6 strains) and Enterococcus faecalis (5 strains) enterocin-producing strains were identified by 16S rDNA analyses. entA, entB, entP and entX structural genes were detected in some isolates. Multiple enterocin structural genes were found in 7 strains. None of the tested enterococci demonstrated β-haemolytic activity and only one strain has gelatinase activity. Six strains showed multiple antibiotic resistance patterns and in addition, vanA and several virulence genes were detected in many strains. Only E. faecalis MBE1-9 showed tyrosine decarboxylase activity and tdc gene was only detected in this strain.

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Private Agricultural R&D: Do the Poor Benefit?

Journal of Agricultural & Food Industrial Organization ◽

10.1515/jafio-2021-0007 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Jock R. Anderson ◽

Regina Birner ◽

Latha Najarajan ◽

Anwar Naseem ◽

Carl E. Pray

Keyword(s):

Poverty Reduction ◽

Agricultural Research ◽

Farming Systems ◽

Agricultural Technologies ◽

Policy Makers ◽

The Public ◽

The Poor ◽

The World ◽

Agricultural Research And Development ◽

The Impact

Abstract Private agricultural research and development can foster the growth of agricultural productivity in the diverse farming systems of the developing world comparable to the public sector. We examine the extent to which technologies developed by private entities reach smallholder and resource-poor farmers, and the impact they have on poverty reduction. We critically review cases of successfully deployed improved agricultural technologies delivered by the private sector in both large and small developing countries for instructive lessons for policy makers around the world.

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Effect of Titanium Dioxide Nanoparticles on the Expression of Efflux Pump and Quorum-Sensing Genes in MDR Pseudomonas aeruginosa Isolates

Antibiotics ◽

10.3390/antibiotics10060625 ◽

2021 ◽

Vol 10 (6) ◽

pp. 625

Author(s):

Fatma Y. Ahmed ◽

Usama Farghaly Aly ◽

Rehab Mahmoud Abd El-Baky ◽

Nancy G. F. M. Waly

Keyword(s):

Titanium Dioxide ◽

Quorum Sensing ◽

Biofilm Formation ◽

Antimicrobial Agents ◽

Efflux Pump ◽

Titanium Dioxide Nanoparticles ◽

Sol Gel ◽

Efflux Pumps ◽

Antibiofilm Activity ◽

The Impact

Most of the infections caused by multi-drug resistant (MDR) P. aeruginosa strains are extremely difficult to be treated with conventional antibiotics. Biofilm formation and efflux pumps are recognized as the major antibiotic resistance mechanisms in MDR P. aeruginosa. Biofilm formation by P. aeruginosa depends mainly on the cell-to-cell communication quorum-sensing (QS) systems. Titanium dioxide nanoparticles (TDN) have been used as antimicrobial agents against several microorganisms but have not been reported as an anti-QS agent. This study aims to evaluate the impact of titanium dioxide nanoparticles (TDN) on QS and efflux pump genes expression in MDR P. aeruginosa isolates. The antimicrobial susceptibility of 25 P. aeruginosa isolates were performed by Kirby–Bauer disc diffusion. Titanium dioxide nanoparticles (TDN) were prepared by the sol gel method and characterized by different techniques (DLS, HR-TEM, XRD, and FTIR). The expression of efflux pumps in the MDR isolates was detected by the determination of MICs of different antibiotics in the presence and absence of carbonyl cyanide m-chlorophenylhydrazone (CCCP). Biofilm formation and the antibiofilm activity of TDN were determined using the tissue culture plate method. The effects of TDN on the expression of QS genes and efflux pump genes were tested using real-time polymerase chain reaction (RT-PCR). The average size of the TDNs was 64.77 nm. It was found that TDN showed a significant reduction in biofilm formation (96%) and represented superior antibacterial activity against P. aeruginosa strains in comparison to titanium dioxide powder. In addition, the use of TDN alone or in combination with antibiotics resulted in significant downregulation of the efflux pump genes (MexY, MexB, MexA) and QS-regulated genes (lasR, lasI, rhll, rhlR, pqsA, pqsR) in comparison to the untreated isolate. TDN can increase the therapeutic efficacy of traditional antibiotics by affecting efflux pump expression and quorum-sensing genes controlling biofilm production.

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The Role of Selected Ecosystem Services in Different Farming Systems in Poland Regarding the Differentiation of Agricultural Land Structure

Sustainability ◽

10.3390/su13126673 ◽

2021 ◽

Vol 13 (12) ◽

pp. 6673

Author(s):

Lidia Luty ◽

Kamila Musiał ◽

Monika Zioło

Keyword(s):

Ecosystem Services ◽

Agricultural Land ◽

Soil Formation ◽

Farming Systems ◽

Agricultural System ◽

Organic System ◽

Supporting Soil ◽

Management Method ◽

The Impact

The functioning of various agroecosystems is nowadays shaped by different farming systems, which may impair their functions, as well as being beneficial to them. The benefits include ecosystem services, defined as economic and noneconomic values gained by humans from ecosystems, through supporting soil formation and nutrient circulation, and the impact of agriculture on climate and biodiversity. Their mutual flow and various disturbances depend on the agroecosystem’s management method, which is associated with the type of management of agricultural land (AL) in individual farms. This paper raises a problem of transformation in the structure of three main farming systems in Poland, in 2004–2018, in relation to the implementation of 16 selected ecosystem services and their scale. Special attention was given to organic farming, as the most environmentally friendly and sustainable. The analysis demonstrates the increase in ALs in that type of production during the analyzed period of time. Disparities of transformation associated with the type of agricultural system were noticeable at the regional level, which were presented in 16 Polish voivodeships. The results of the analysis confirm that the organic system, which is an important carrier of various ecosystem services, gained a stable position. Moreover, areas with integrated farming still do not exceed 0.5% of total agricultural lands in such voivodeships. The analysis of factors influencing the deterioration or disappearance of selected environmental services characterizing agricultural systems indicates the need to depart from an intensive conventional management system.

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Virulence and Antimicrobial Resistance Profiles of Salmonella enterica Serovars Isolated from Chicken at Wet Markets in Dhaka, Bangladesh

Microorganisms ◽

10.3390/microorganisms9050952 ◽

2021 ◽

Vol 9 (5) ◽

pp. 952

Author(s):

Nure Alam Siddiky ◽

Md Samun Sarker ◽

Md. Shahidur Rahman Khan ◽

Ruhena Begum ◽

Md. Ehsanul Kabir ◽

...

Keyword(s):

Antimicrobial Resistance ◽

Salmonella Enterica ◽

Virulence Genes ◽

Health Concern ◽

Production Cycle ◽

Salmonella Spp ◽

Native Chicken ◽

Resistance Patterns ◽

Research Findings ◽

Native Chickens

Virulent and multi drug resistant (MDR) Salmonellaenterica is a foremost cause of foodborne diseases and had serious public health concern globally. The present study was undertaken to identify the pathogenicity and antimicrobial resistance (AMR) profiles of Salmonellaenterica serovars recovered from chicken at wet markets in Dhaka, Bangladesh. A total of 870 cecal contents of broiler, sonali, and native chickens were collected from 29 wet markets. The overall prevalence of S. Typhimurium, S. Enteritidis, and untyped Salmonella spp., were found to be 3.67%, 0.57%, and 1.95% respectively. All isolates were screened by polymerase chain reaction (PCR) for eight virulence genes, namely invA, agfA, IpfA, hilA, sivH, sefA, sopE, and spvC. S. Enteritidis isolates carried all virulence genes whilst S. Typhimurium isolates carried six virulence genes except sefA and spvC. A diverse phenotypic and genotypic AMR pattern was found. Harmonic descending trends of resistance patterns were observed among the broiler, sonali, and native chickens. Interestingly, virulent and MDR Salmonella enterica serovars were found in native chicken, although antimicrobials were not used in their production cycle. The research findings anticipate that virulent and MDR Salmonella enterica are roaming in the wet markets which can easily anchor to the vendor, consumers, and in the food chain.

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Correcting Misperceptions About Genetically Modified Food on Social Media: Examining the Impact of Experts, Social Media Heuristics, and the Gateway Belief Model

Science Communication ◽

10.1177/1075547020981375 ◽

2020 ◽

pp. 107554702098137

Author(s):

Leticia Bode ◽

Emily K. Vraga ◽

Melissa Tully

Keyword(s):

Social Media ◽

Food Safety ◽

Genetically Modified ◽

Human Consumption ◽

Genetically Modified Food ◽

The Public ◽

Scientific Consensus ◽

Gm Food ◽

Belief Model ◽

The Impact

We experimentally test whether expert organizations on social media can correct misperceptions of the scientific consensus on the safety of genetically modified (GM) food for human consumption, as well as what role social media cues, in the form of “likes,” play in that process. We find expert organizations highlighting scientific consensus on GM food safety reduces consensus misperceptions among the public, leading to lower GM misperceptions and boosting related consumption behaviors in line with the gateway belief model. Expert organizations’ credibility may increase as a result of correction, but popularity cues do not seem to affect misperceptions or credibility.

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Rural Roads Are Paving the Way for Land-Use Intensification in the Uplands of Laos

Land ◽

10.3390/land10030330 ◽

2021 ◽

Vol 10 (3) ◽

pp. 330

Author(s):

Jean-Christophe Castella ◽

Sonnasack Phaipasith

Keyword(s):

Land Use ◽

Management Practices ◽

Management Strategies ◽

Farming Systems ◽

Long Term Effects ◽

Group Discussions ◽

Rural Roads ◽

External Resources ◽

Hybrid Maize ◽

The Impact

Road expansion has played a prominent role in the agrarian transition that marked the integration of swidden-based farming systems into the market economy in Southeast Asia. Rural roads deeply altered the landscape and livelihood structures by allowing the penetration of boom crops such as hybrid maize in remote territories. In this article, we investigate the impact of rural road developments on livelihoods in northern Laos through a longitudinal study conducted over a period of 15 years in a forest frontier. We studied adaptive management strategies of local stakeholders through the combination of individual surveys, focus group discussions, participatory mapping and remote-sensing approaches. The study revealed the short-term benefits of the maize feeder roads on poverty alleviation and rural development, but also the negative long-term effects on agroecosystem health and agricultural productivity related to unsustainable land use. Lessons learnt about the mechanisms of agricultural intensification helped understanding the constraints faced by external interventions promoting sustainable land management practices. When negotiated by local communities for their own interest, roads may provide livelihood-enhancing opportunities through access to external resources, rather than undermining them.

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Agricultural subsidies and global greenhouse gas emissions

Nature Communications ◽

10.1038/s41467-021-22703-1 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

David Laborde ◽

Abdullah Mamun ◽

Will Martin ◽

Valeria Piñeiro ◽

Rob Vos

Keyword(s):

Agricultural Production ◽

Ghg Emissions ◽

Farming Systems ◽

Government Support ◽

Consumer Prices ◽

High Emission ◽

The Government ◽

Agriculture And Food ◽

The Impact ◽

Global Emissions

AbstractAgricultural production is strongly affected by and a major contributor to climate change. Agriculture and land-use change account for a quarter of total global emissions of greenhouse gases (GHG). Agriculture receives around US$600 billion per year worldwide in government support. No rigorous quantification of the impact of this support on GHG emissions has been available. This article helps fill the void. Here, we find that, while over the years the government support has incentivized the development of high-emission farming systems, at present, the support only has a small impact in terms of inducing additional global GHG emissions from agricultural production; partly because support is not systematically biased towards high-emission products, and partly because support generated by trade protection reduces demand for some high-emission products by raising their consumer prices. Substantially reducing GHG emissions from agriculture while safeguarding food security requires a more comprehensive revamping of existing support to agriculture and food consumption.

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