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1.
Ecotoxicol Environ Saf ; 220: 112413, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34139628

RESUMO

Aerobic composting is commonly used to dispose livestock manure and is an efficient way to reduce antibiotic resistance genes (ARGs). Here, the effects of different quality substrates on the fate of ARGs were assessed during manure composting. Results showed that the total relative abundances of ARGs and intI1 in additive treatments were lower than that in control, and high quality treatment with low C/N ratio and lignin significantly decreased the relative abundance of tetW, ermB, ermC, sul1 and sul2 at the end of composting. Additionally, higher quality treatment reduced the relative abundances of some pathogens such as Actinomadura and Pusillimonas, and some thermotolerant degrading-related bacteria comprising Pseudogracilibacillus and Sinibacillus on day 42, probably owing to the change of composting properties in piles. Structural equation models (SEMs) further verified that the physiochemical properties of composting were the dominant contributor to the variations in ARGs and they could also indirectly impact ARGs by influencing bacterial community and the abundance of intI1. Overall, these findings indicated that additives with high quality reduced the reservoir of antibiotic resistance genes of livestock manure compost.


Assuntos
Compostagem/métodos , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos/efeitos dos fármacos , Esterco/análise , Esterco/microbiologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Carbono/análise , Carbono/farmacologia , Galinhas/microbiologia , Lignina/análise , Lignina/farmacologia , Microbiota/efeitos dos fármacos , Nitrogênio/análise , Nitrogênio/farmacologia
2.
Int J Food Microbiol ; 350: 109246, 2021 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-34034079

RESUMO

Salmonella enterica is a major cause of foodborne diseases, and is also an important pathogenic bacterium in poultry industry. Whole genome sequencing (WGS) has become a crucial molecular typing technology used for the surveillance of the pathogenic bacteria. In the present study, we adopted WGS for tracking transmission of S. enterica in the production chain of broiler chickens. A total of 74 S. enterica strains were isolated from the different steps of breeding and slaughtering in a large production enterprise in Sichuan Province, China. The isolation rate of Salmonella was the highest in procedure of defeathering (50.0%) and evisceration (36.7%). Serotype identification showed that 74 Salmonella isolates included 7 serotypes, among which Mbandaka accounted for the highest proportions (35.1%). WGS revealed that 74 strains belonged to 7 different sequence types (STs), as well as 7 different ribosomal STs and 35 core genome STs. cgMLST-based Minimum Spanning Trees and phylogenetic tree based on the SNPs indicated that three serotypes, Mbandaka, Indiana and Kentucky, could be clonally transmitted between broiler farm and slaughterhouse. Heterogeneous resistant phenotypes and genotypes were found in two serotypes, Indiana and Kentucky. Our study indicated WGS in an accurate tool for molecular typing of S. enterica. Routine surveillance of S. enterica in the production chain of broiler chickens is needed.


Assuntos
Galinhas/microbiologia , Genoma Bacteriano/genética , Tipagem Molecular/métodos , Aves Domésticas/microbiologia , Salmonelose Animal/transmissão , Salmonella enterica/genética , Animais , Antibacterianos/farmacologia , China/epidemiologia , Filogenia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/transmissão , Produtos Avícolas , Salmonelose Animal/microbiologia , Salmonella enterica/isolamento & purificação , Sorogrupo , Sequenciamento Completo do Genoma
3.
Food Microbiol ; 98: 103795, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875223

RESUMO

Broiler meat is considered as the most important source of the foodborne pathogen Campylobacter jejuni. Exposure to stress conditions encountered during the slaughtering process may induce bacterial adaptation mechanisms, and enhance or decrease pathogen resistance to subsequent stress. This adaptation may result from changes in bacterial gene expression. This study aims to accurately quantify the expression of selected C. jejuni genes after stresses inspired from the poultry slaughtering process. RT-qPCR was used to quantify gene expression of 44 genes in three strains after successive heat and cold stresses. Main results indicated that 26 genes out of 44 were differentially expressed following the successive thermal stresses. Three clusters of genes were differentially expressed according to the strain and the stress condition. Up-regulated genes mainly included genes involved in the heat shock response, whereas down-regulated genes belonged to metabolic pathways (such as lipid, amino-acid metabolisms). However, four genes were similarly overexpressed in the three strains; they might represent indicators of the thermal stress response at the species scale. Advances in the molecular understanding of the stress response of pathogenic bacteria, such as Campylobacter, in real-life processing conditions will make it possible to identify technological levers and better mitigate the microbial risk.


Assuntos
Proteínas de Bactérias/genética , Infecções por Campylobacter/veterinária , Campylobacter jejuni/fisiologia , Galinhas/microbiologia , Matadouros , Animais , Proteínas de Bactérias/metabolismo , Infecções por Campylobacter/microbiologia , Campylobacter jejuni/genética , Campylobacter jejuni/metabolismo , Regulação Bacteriana da Expressão Gênica , Carne/microbiologia , Doenças das Aves Domésticas/microbiologia , Reação em Cadeia da Polimerase em Tempo Real , Estresse Fisiológico
4.
Trop Anim Health Prod ; 53(2): 252, 2021 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-33829333

RESUMO

The aim of present study was to determine the effects of supplementation of either synbiotic or probiotic on growth performance and carcass characteristics, gut health, cecal microbiota prolife and apparent ileal digestibility of protein, amino acids, and energy in broilers. Two hundred and forty-day-old straight-run broilers (Ross 308) were allotted randomly to 1 of 5 dietary treatments including basal diet (control), supplemented with either synbiotic (Nutromax P) or probiotic (Actera), each at 0.5 and 1 g/kg of the diet for 5 weeks. The overall findings of the study indicated better (p < 0.05) growth performance of broilers by synbiotic supplementation (1 g/kg) compared with those fed probiotic (1 g/kg) supplemented and control diets. The broilers consuming diet supplemented with 1 g/kg synbiotic has an increased carcass yield in comparison with those fed control diet. The findings of gut health indicated significantly increased villus height and goblet cells, by synbiotic supplementation (1 g/kg), compared with control diet in broilers. The broilers fed 1 g/kg synbiotic supplemented diets had 18% increased protein, 9 to 31% higher amino acid, and 34% better energy digestibility, whereas 8.4% decreased protein digestibility in broilers fed probiotic (1 g/kg) supplemented compared with control diet in broilers. The broilers fed synbiotic (1 g/kg) supplemented diets had increased cecal Lactobacillus and decreased Salmonella, E. coli, and Clostridium count compared with those fed control diet. In conclusion, synbiotic supplementation (1 g/kg) resulted in improved production performance, balanced cecal microbial composition, and better digestibility of nutrients in broilers compared with those fed control and diets supplemented with probiotics.


Assuntos
Aminoácidos/metabolismo , Ceco/microbiologia , Galinhas , Dieta/veterinária , Digestão , Metabolismo Energético , Íleo/fisiologia , Fermento Seco , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas/anatomia & histologia , Galinhas/crescimento & desenvolvimento , Galinhas/microbiologia , Galinhas/fisiologia , Suplementos Nutricionais/análise , Escherichia coli , Microbioma Gastrointestinal , Proteínas/metabolismo , Saccharomyces cerevisiae
5.
Appl Environ Microbiol ; 87(10)2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33712430

RESUMO

Enterococci are ubiquitous opportunistic pathogens that have become a major public health issue globally. The increasing prevalence of antimicrobial resistance in hospital-adapted enterococci had been thought to originate from livestock. However, this association between livestock and hospital-adapted enterococci is currently unclear. This study investigates the antimicrobial susceptibilities of enterococci isolated from pig cecal samples and compares the genomic characteristics of Enterococcus faecium from pigs to those of isolates from meat chickens and from human sepsis cases. From 200 cecal samples, antimicrobial susceptibility testing was performed for E. faecium (n = 84), E. hirae (n = 36), and E. faecalis (n = 17). Whole-genome sequencing was performed for all E. faecium isolates, and the sequences were compared to those of previously studied isolates from meat chickens and human sepsis cases through bioinformatics analysis. Resistance (non-wild type) to erythromycin, gentamicin, tetracycline, ampicillin, daptomycin, virginiamycin, and quinupristin-dalfopristin was identified. More importantly, except for a single isolate harboring the vanC operon, no resistance was observed in the three species to vancomycin, teicoplanin, and linezolid, which are critically important antimicrobials used to treat enterococcal infections in humans. The E. faecium isolates from chickens were genetically distinct from human and pig isolates, which were more closely related. Human strains that were closely related to pig strains were not typical "hospital-adapted strains" as previously identified. The results of this study show that enterococci from Australian finisher pigs are not a source of resistance to critically important antimicrobials and that E. faecium from pigs is not part of the current human hospital-adapted population.IMPORTANCE Resistance to the critically important antimicrobials vancomycin, teicoplanin, and linezolid is not found in enterococci collected from Australian finisher pigs. However, some antimicrobial resistance was observed. In particular, resistance to quinupristin-dalfopristin, a combination of two streptogramin class antimicrobials, was identified despite the absence of streptogramin use Australia-wide since 2005. Other observed resistance among enterococci from pigs include chloramphenicol, erythromycin, and tetracycline resistance. Genomic comparison of E. faecium from Australian pigs to isolates collected from previous studies on chickens and humans indicate that E. faecium from pigs are genetically more similar to those of humans than those from chickens. Despite the increased genetic similarities, E. faecium strains from pigs are phylogenetically distinct and did not belong to the dominant sequence types found in hospital-adapted strains causing sepsis in humans. Therefore, the results indicate that Australian finisher pigs are not a source of hospital-adapted E. faecium in Australia.


Assuntos
Antibacterianos/farmacologia , Ceco/microbiologia , Farmacorresistência Bacteriana , Enterococcus/efeitos dos fármacos , Animais , Austrália , Galinhas/microbiologia , Farmacorresistência Bacteriana/genética , Enterococcus/genética , Enterococcus/isolamento & purificação , Monitoramento Ambiental , Genoma Bacteriano , Humanos , Testes de Sensibilidade Microbiana , Sepse/microbiologia , Suínos
6.
Lett Appl Microbiol ; 73(1): 54-63, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33765334

RESUMO

Lactic Acid Bacteria (LAB) regulate and maintain the stability of healthy microbial flora, inhibit the adhesion of pathogenic bacteria and promote the colonization of beneficial micro-organisms. The drug resistance and pathogenicity of Salmonella enteritis SE47 isolated from retail eggs were investigated. Meanwhile, Enterococcus faecalis L76 and Lactobacillus salivarius LAB35 were isolated from intestine of chicken. With SE47 as indicator bacteria, the diameters of L76 and LAB35 inhibition zones were 12 mm and 8·5 mm, respectively, by agar inhibition circle method, which indicated that both of them had inhibitory effect on Salmonella, and L76 had better antibacterial effect; two chicken-derived lactic acid bacteria isolates and Salmonella SE47 were incubated with Caco-2. The adhesion index of L76 was 17·5%, which was much higher than that of LAB35 (10·21%) and SE47 (4·89%), this experiment shows that the higher the bacteriostatic effect of potential probiotics, the stronger the adhesion ability; then Caco-2 cells were incubated with different bacteria, and the survival of Caco-2 cells was observed by flow cytometry. Compared with Salmonella SE47, the results showed that lactic acid bacteria isolates could effectively protect Caco-2 cells; finally, after different bacteria incubated Caco-2 cells, according to the cytokine detection kit, the RNA of Caco-2 cells was extracted and transcribed into cDNA, then detected by fluorescence quantitative PCR, the results showed that L76 could protect Caco-2 cells from the invasion of Salmonella SE47, with less cell membrane rupture and lower expression of MIF and TNF genes. Therefore, the lactic acid bacteria isolates can effectively inhibit the adhesion of Salmonella and protect the integrity of intestinal barrier.


Assuntos
Antibiose/fisiologia , Ovos/microbiologia , Lactobacillales/fisiologia , Infecções por Salmonella/microbiologia , Salmonella enterica/fisiologia , Animais , Células CACO-2 , Galinhas/microbiologia , Farmacorresistência Bacteriana/fisiologia , Enterococcus faecalis/isolamento & purificação , Enterococcus faecalis/fisiologia , Humanos , Lactobacillus salivarius/isolamento & purificação , Lactobacillus salivarius/fisiologia , Probióticos/isolamento & purificação , Probióticos/farmacologia , Salmonella enterica/patogenicidade
7.
Lett Appl Microbiol ; 72(6): 783-790, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33735446

RESUMO

This study was conducted to isolate and identify extended-spectrum beta-lactamase (ESBL)-producing Enterobacterales in conventional and organic chicken meats, which were sold in Turkey. A total of 200 raw chicken meat sample (100 conventional and 100 organic) were used as material. Classic culture technique based on chromogenic method was used for the isolation of bacteria, and the identification was performed with VITEK MS. Phenotypic ESBL production was detected by combined disc diffusion method. Gene regions responsible for ESBL production were determined by PCR. MIC values of isolates were detected by VITEK 2. Phenotypic ESBL-producing Enterobacterales were detected in 46% of conventional chicken meats and in 22% of organic chicken meats. Of the 115 isolates obtained, 97 (84%) were Escherichia coli, 12 (10%) were Klebsiella pneumoniae, four (3·48%) were Serratia fonticola, one (0·87%) was Rahnella aquatilis, and one (0·87%) was Serratia liquefaciens. PCR analysis revealed that 109 of 115 isolates (94·78%) contained at least one of the blaCTX-M , blaTEM , and blaSHV genes. Of the 115 ESBL-producing isolates, 103 (89·57%) were found resistant to at least one antibiotic except for the ß-lactam group. The contamination level of ESBL-producing Enterobacterales was higher in conventional chicken meats (P < 0·001).


Assuntos
Escherichia coli/genética , Klebsiella pneumoniae/genética , Carne/microbiologia , Serratia/genética , beta-Lactamases/genética , Animais , Antibacterianos/farmacologia , Galinhas/microbiologia , Escherichia coli/efeitos dos fármacos , Infecções por Escherichia coli/microbiologia , Microbiologia de Alimentos , Klebsiella pneumoniae/efeitos dos fármacos , Reação em Cadeia da Polimerase , Serratia/efeitos dos fármacos , Turquia
8.
Food Microbiol ; 97: 103751, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33653524

RESUMO

Campylobacter is a major cause of foodborne diarrheal infections in the United States of America (USA). This study aimed to elucidate the patterns of Campylobacter foodborne outbreaks temporally and spatially concerning food vehicles. We collected the data of foodborne outbreaks from 1998 to 2016 reported to the Centers for Disease Control and Prevention. The incidence rate of outbreaks for each food source was calculated and analyzed for each variable including season, food location, and census region. Overall, 465 single-state outbreaks and 8003 cases were reported during 1998-2016. Outbreaks were frequently attributed to dairy products (32%), chicken (17%) and vegetables (6%). Binomial regression analysis showed that compared to chicken items, the highest rate ratio of outbreaks was associated with dairy products (1.86) followed by vegetables (1.35) and meat products (0.76). More outbreaks were reported in the summer (35%) followed by the spring (26%) and fall (22%) season. We found that the highest number of outbreaks occurred in the West 159 (34%) and Midwest 137 (29%) census regions. The study highlights the role of dairy, chicken, and vegetables as food vehicles in Campylobacter outbreaks. Findings from this study can help in devising strategies to mitigate the increasing occurrence of Campylobacter foodborne outbreaks.


Assuntos
Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Doenças Transmitidas por Alimentos/epidemiologia , Doenças Transmitidas por Alimentos/microbiologia , Animais , Galinhas/microbiologia , Laticínios/microbiologia , Contaminação de Alimentos/estatística & dados numéricos , Humanos , Carne/microbiologia , Estações do Ano , Estados Unidos/epidemiologia , Verduras/microbiologia
9.
Food Microbiol ; 97: 103754, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33653527

RESUMO

The microbial composition of the food production environment plays an important role in food safety and quality. This study employed both 16 S rRNA gene sequencing technology and culture-based techniques to investigate the bacterial microbiota of an egg production facility comprising of both free-range and conventional cage housing systems. The study also aimed to detect the presence of Salmonella enterica and determine whether its presence was positively or negatively associated with other taxa. Our findings revealed that microbiota profiles of free-range and cage houses differ considerably in relation to the relative abundance and diversity with a number of taxa unique to each system and to individual sampling sites within sheds. Core to each housing system were known inhabitants of the poultry gastrointestinal tracts, Romboutsia and Turicibacter, as well as common spoilage bacteria. Generally, free-range samples contained fewer taxa and were dominated by Staphylococcus equorum, differentiating them from the cage samples. Salmonella enterica was significantly associated with the presence of a taxa belonging to the Carnobacteriaceae family. The results of this study demonstrate that the diversity and composition of the microbiota is highly variable across egg layer housing systems, which could have implications for productivity, food safety and spoilage.


Assuntos
Criação de Animais Domésticos/métodos , Bactérias/isolamento & purificação , Galinhas/microbiologia , Ovos/análise , Microbiota , Salmonella enterica/isolamento & purificação , Animais , Bactérias/classificação , Bactérias/genética , Galinhas/fisiologia , Feminino , Masculino , Oviposição , Salmonella enterica/classificação , Salmonella enterica/genética
10.
Toxins (Basel) ; 13(2)2021 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-33671260

RESUMO

The objective of this study was to evaluate the efficacy of mycotoxin binders in reducing the adverse effects of co-occurring dietary aflatoxin B1 (AFB1), deoxynivalenol (DON) and ochratoxin A (OTA) on laying hens. Three hundred and sixty 26-week-old Roman laying hens were randomly allocated into four experimental groups with 10 replicates of nine birds each. The four groups received either a basal diet (BD; Control), a BD supplemented with 0.15 mg/kg AFB1 + 1.5 mg/kg DON + 0.12 mg/kg OTA (Toxins), a BD + Toxins with Toxo-HP binder (Toxins + HP), or a BD + Toxins with TOXO XL binder (Toxins + XL) for 12 weeks. Compared to the control, dietary supplementation of mycotoxins decreased (P < 0.10) total feed intake, total egg weight, and egg-laying rate, but increased feed/egg ratio by 2.5-6.1% and mortality during various experimental periods. These alterations induced by mycotoxins were alleviated by supplementation with both TOXO HP and XL binders (P < 0.10). Furthermore, dietary mycotoxins reduced (P < 0.05) eggshell strength by 12.3% and caused an accumulation of 249 µg/kg of DON in eggs at week 12, while dietary supplementation with TOXO HP or XL mitigated DON-induced changes on eggshell strength and prevented accumulation of DON in eggs (P < 0.05). Moreover, dietary mycotoxins increased relative liver weight, but decreased spleen and proventriculus relative weights by 11.6-22.4% (P < 0.05). Mycotoxin exposure also increased alanine aminotransferase activity and reduced immunoglobulin (Ig) A, IgM, and IgG concentrations in serum by 9.2-26.1% (P < 0.05). Additionally, mycotoxin exposure induced histopathological damage and reduced villus height, villus height/crypt depth, and crypt depth in duodenum, jejunum and (or) ileum (P < 0.05). Notably, most of these histological changes were mitigated by supplementation with both TOXO HP and XL (P < 0.05). In conclusion, the present study demonstrated that the mycotoxin binders TOXO HP and XL can help to mitigate the combined effects of AFB1, DON, and OTA on laying hen performance, egg quality, and health.


Assuntos
Aflatoxina B1/análise , Ração Animal/análise , Bentonita/administração & dosagem , Parede Celular , Galinhas/crescimento & desenvolvimento , Suplementos Nutricionais , Ovos , Ocratoxinas/análise , Tricotecenos/análise , Leveduras , Aflatoxina B1/toxicidade , Ração Animal/microbiologia , Ração Animal/toxicidade , Criação de Animais Domésticos , Animais , Galinhas/microbiologia , Feminino , Microbiologia de Alimentos , Ocratoxinas/toxicidade , Tricotecenos/toxicidade
11.
Int J Food Microbiol ; 344: 109110, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33657496

RESUMO

Salmonella genus has foodborne pathogen species commonly involved in many outbreaks related to the consumption of chicken meat. Many studies have aimed to model bacterial inactivation as a function of the temperature. Due to the large heterogeneity of the results, a unified description of Salmonella spp. inactivation behavior is hard to establish. In the current study, by evaluating the root mean square errors, mean absolute deviation, and Akaike and Bayesian information criteria, the double Weibull model was considered the most accurate primary model to fit 61 datasets of Salmonella inactivation in chicken meat. Results can be interpreted as if the bacterial population is divided into two subpopulations consisting of one more resistant (2.3% of the total population) and one more sensitive to thermal stress (97.7% of the total population). The thermal sensitivity of the bacteria depends on the fat content of the chicken meat. From an adapted version of the Bigelow secondary model including both temperature and fat content, 90% of the Salmonella population can be inactivated after heating at 60 °C of chicken breast, thigh muscles, wings, and skin during approximately 2.5, 5.0, 9.5, and 57.4 min, respectively. The resulting model was applied to four different non-isothermal temperature profiles regarding Salmonella growth in chicken meat. Model performance for the non-isothermal profiles was evaluated by the acceptable prediction zone concept. Results showed that >80% of the predictions fell in the acceptable prediction zone when the temperature changes smoothly at temperature rates lower than 20 °C/min. Results obtained can be used in risk assessment models regarding contamination with Salmonella spp. in chicken parts with different fat contents.


Assuntos
Galinhas/microbiologia , Temperatura Alta , Carne/microbiologia , Intoxicação Alimentar por Salmonella/prevenção & controle , Salmonella/crescimento & desenvolvimento , Animais , Teorema de Bayes , Contagem de Colônia Microbiana , Microbiologia de Alimentos , Salmonella/classificação
12.
Int J Food Microbiol ; 344: 109116, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33676332

RESUMO

Staphylococcus aureus is among the most common zoonotic pathogens originating from animals consumed as food, especially raw chicken meat (RCM). As far as we know, this might be the first report that explores the efficacy of metal oxide nanoparticles (MONPs), such as zinc peroxide nanoparticles (ZnO2-NPs), zinc oxide nanoparticles (ZnO-NPs), and titanium dioxide nanoparticles (TiO2-NPs) against multidrug resistant (MDR) and/or pandrug resistant (PDR) S. aureus strains with a strong biofilm-producing ability isolated from RCM and giblets. The overall prevalence of coagulase-positive staphylococci was 21%, with a contamination level range between 102 and 104 CFU/g. The incidence of virulence genes See (21/36), pvl (16/36), clfA (15/36), sec (12/36), tst (12/36), and sea (11/36) among S. aureus strains were relatively higher those of seb, sed, fnbA, and fnbB. For antimicrobial resistance gene distribution, most strains harbored the blaZ gene (25/36), aacA-aphD gene (24/36), mecA gene (22/36), vanA gene (20/36), and apmA gene (20/36) confirmed the prevalence of MDR among S. aureus of RCM products. However, cfr (11/36), spc (9/36), and aadE (7/36) showed a relatively lower existence. The data of antibiogram resistance profiles was noticeably heterogeneous (25 patterns) with 32 MDR and four PDR S. aureus strains. All tested strains had a very high MAR index value (>0.2) except the P11 pattern (GEN, MXF, PMB), which showed a MAR index of 0.19. Among the strong biofilm-producing ability (BPA), 14 (70%) strains were isolated from wet markets, while only six strong BPA strains were isolated from supermarkets. The mean values of BPA ranged from 2.613 ± 0.04 to 11.013 ± 0.05. Clearly, ZnO2-NPs show significant inhibitory activity against S. aureus strains compared with those produced by the action of ZnO-NPs and TiO2-NPs. The results of anti-inflammatory activity suggest ZnO2-NPs as a lead compound for designing an alternative antimicrobial agent against drug-resistant and strong biofilm-producing S. aureus isolates from retail RCM and giblets.


Assuntos
Antibacterianos/farmacologia , Contaminação de Alimentos/prevenção & controle , Staphylococcus aureus/crescimento & desenvolvimento , Titânio/farmacologia , Óxido de Zinco/farmacologia , Animais , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Galinhas/microbiologia , Farmacorresistência Bacteriana Múltipla/genética , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Carne/microbiologia , Nanopartículas Metálicas , Testes de Sensibilidade Microbiana , Infecções Estafilocócicas/epidemiologia , Infecções Estafilocócicas/prevenção & controle , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/isolamento & purificação , Virulência/genética
13.
Int J Food Microbiol ; 344: 109109, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33677191

RESUMO

The objective of the present study was to characterize Salmonella enterica serovar Infantis isolated from chicken meat determining their clonal relationships with S. Infantis isolated from children with diarrhea. Fifteen meat-recovered S. Infantis were analyzed. Susceptibility levels to 14 antibacterial agents, the presence of ESBL and that of inducible plasmid-mediated AmpC (i-pAmpC) were determined by phenotypical methods. The presence of ESBL and pAmpC was confirmed by PCR, and detected ESBL-encoding genes were sequenced and their transferability tested by conjugation. The presence of gyrA mutations as well as Class 1 integrons was determined by PCR. Clonal relationships were established by REP-PCR and RAPD. In addition, 25 clinical isolates of S. Infantis were included in clonality studies. All meat-recovered S. Infantis were MDR, showing resistance to ampicillin, nitrofurans and quinolones, while none was resistant to azithromycin, ceftazidime or imipenem. ESBL (blaCTX-M-65) and i-pAmpC (blaDHA) were detected in 2 and 5 isolates respectively (in one case concomitantly), with blaCTX-M-65 being transferable through conjugation. In addition, 1 isolate presented a blaSHV gene. All isolates presented D87Y at GyrA, nalidixic acid active efflux pump and a Class 1 integron of ~1000 bp (aadA1). Clonal analysis showed that all isolates were related. Further they were identical to MDR blaCTX-M-65-producing S. Infantis isolates causing children diarrhea in Lima. The dissemination of MDR blaCTX-M-65-producing S. Infantis between marketed meat and children highlights a public health problem which needs be controlled at livestock level.


Assuntos
Proteínas de Bactérias/genética , Carne/microbiologia , Intoxicação Alimentar por Salmonella/transmissão , Salmonelose Animal/transmissão , Salmonella enterica/genética , beta-Lactamases/genética , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Galinhas/microbiologia , Criança , Humanos , Integrons/genética , Plasmídeos/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Intoxicação Alimentar por Salmonella/microbiologia , Salmonelose Animal/microbiologia , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/isolamento & purificação , Sorogrupo , beta-Lactamases/metabolismo
14.
Int J Food Microbiol ; 345: 109150, 2021 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-33735782

RESUMO

Glycerol monolaurate (GML) is a monoglycerol ester of the fatty lauric acids, which has a wide-spectrum antimicrobial capacity, but fails to inactivate Gram-negative bacteria, especial Salmonella. To enhance the population reduction rate of GML for Salmonella, this reagent was combined with three disinfectants: lactic acid (LA), cetylpyridinium chloride (CPC), and trisodium phosphate (TSP), which can present acid, neutral, and alkaline in solution, respectively. The results showed that the 1% GML and a complex disinfectant (0.5% GML-0.025% LA) could powerfully inactivate Salmonella. Their population reduction rates respectively were able to achieve 99.92% and 98.29% with the vortex treatment, indicating that the vortex treatment could improve GML to destruct the outer membrane of Salmonella. During the simulation test of the soaking and rinse processing of chicken, for a short time (0 h), the effect of 0.5% GML-0.025% LA compound was better and more suitable for instantaneous inactivation than others, while for a long time (4 h), 1% GML exhibited a better bactericidal effect, which indicated it to be more suitable for long-term bacteriostasis. The characterization of color and texture for chicken samples were determined using Colormeter Ci7600, TA.XT Plus and Hyper-spectral Imager, which demonstrated that all samples treated by these complex disinfectants were not significantly different from untreated group. In conclusion, GML is a potential and superior disinfectant for the chicken process.


Assuntos
Desinfetantes/farmacologia , Doenças Transmitidas por Alimentos/prevenção & controle , Lauratos/farmacologia , Monoglicerídeos/farmacologia , Salmonella/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Cetilpiridínio/farmacologia , Galinhas/microbiologia , Contaminação de Alimentos/análise , Microbiologia de Alimentos , Ácido Láctico/farmacologia , Fosfatos/farmacologia
15.
Poult Sci ; 100(3): 100800, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33518302

RESUMO

A meta-analysis of 19 floor-pen trials (579 replicate pen observations) in diverse geographies, basal diets, seasons, and medication programs was carried out to evaluate the effects of 2 precision glycan microbiome metabolic modulators (MMM1 and MMM2) on the performance of broiler chickens. In each trial, negative-control (NC) diets were compared with either MMM1 (14 trials) or MMM2 (8 trials), supplemented at an intended dose of 500 g/MT from hatch to 31 to 42 d. A dose response of MMM2 was evaluated in 8 trials at doses of 100, 250, 500, and 1,000 g/MT, not all present in each trial. Linear mixed-effect models were constructed for the final BW, cumulative feed intake, feed conversion ratio (FCR) corrected by mortality and BW (cFCR), and mortality, with Treatment as the fixed effect, nested random effects of Trial and Block, and adjustments for heterogeneity of variances. A significance level of P < 0.05 was used. In one of the studies, cecal content samples were collected at 42 d for analysis of microbiome gene abundance. Microbiome metabolic modulator 2 exhibited a reduction of the cFCR of 0.06 g feed/g BW gain compared with the NC and 0.03 g feed/g BW gain compared with MMM1, whereas MMM1 reduced the cFCR by 0.03 g feed/g BW gain compared with NC. Both MMM1 and MMM2 increased the final BW compared with the NC by 43 and 48 g/bird, respectively, with no difference among them. Compared with NC, feed intake was increased by MMM1 (+51 g/bird) and reduced by MMM2 (-74 g/bird). A one-directional dose response of the MMM2 ingredient was observed for the final BW (increasing) and cFCR (decreasing), whereas the feed intake response reached a minimum at 500 g/MT. The metagenomic analysis confirmed an increase in the abundance of genes belonging to the acrylate pathway, which is involved in propionate production, as well as arginine-N-succinyl transferase which is involved in the catabolism of arginine, in response to MMM2. Differential glycan structures of the MMM had an impact on the size and consistency of performance effects in broilers.


Assuntos
Aminoácidos , Fenômenos Fisiológicos da Nutrição Animal , Ceco , Galinhas , Suplementos Nutricionais , Metabolismo Energético , Microbiota , Aminoácidos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos , Animais , Ceco/microbiologia , Galinhas/crescimento & desenvolvimento , Galinhas/metabolismo , Galinhas/microbiologia , Dieta/veterinária , Suplementos Nutricionais/análise , Metabolismo Energético/efeitos dos fármacos , Metagenoma , Microbiota/efeitos dos fármacos , Distribuição Aleatória
16.
J Vis Exp ; (167)2021 01 27.
Artigo em Inglês | MEDLINE | ID: mdl-33586704

RESUMO

A non-coding small RNA (sRNA) is a new factor to regulate gene expression at the post-transcriptional level. A kind of sRNA MicC, known in Escherichia coli and Salmonella Typhimurium, could repress the expression of outer membrane proteins. To further investigate the regulation function of micC in Salmonella Enteritidis, we cloned the micC gene in the Salmonella Enteritidis strain 50336, and then constructed the mutant 50336ΔmicC by the λ Red-based recombination system and the complemented mutant 50336ΔmicC/pmicC carrying recombinant plasmid pBR322 expressing micC. qRT-PCR results demonstrated that transcription of ompD in 50336ΔmicC was 1.3-fold higher than that in the wild type strain, while the transcription of ompA and ompC in 50336ΔmicC were 2.2-fold and 3-fold higher than those in the wild type strain. These indicated that micC represses the expression of ompA and ompC. In the following study, the pathogenicity of 50336ΔmicC was detected by both infecting 6-week-old Balb/c mice and 1-day-old chickens. The result showed that the LD50 of the wild type strain 50336, the mutants 50336ΔmicC and 50336ΔmicC/pmicC for 6-week-old Balb/c mice were 12.59 CFU, 5.01 CFU, and 19.95 CFU, respectively. The LD50 of the strains for 1-day-old chickens were 1.13 x 109 CFU, 1.55 x 108 CFU, and 2.54 x 108 CFU, respectively. It indicated that deletion of micC enhanced virulence of S. Enteritidis in mice and chickens by regulating expression of outer membrane proteins.


Assuntos
Proteínas de Bactérias/genética , Proteínas de Membrana/genética , RNA não Traduzido/genética , Salmonella enteritidis/genética , Salmonella enteritidis/patogenicidade , Animais , Proteínas de Bactérias/metabolismo , Galinhas/microbiologia , Regulação Bacteriana da Expressão Gênica , Proteínas de Membrana/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Mutação/genética , Plasmídeos/genética , RNA Bacteriano/genética , RNA Bacteriano/isolamento & purificação , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , RNA não Traduzido/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Recombinação Genética/genética , Salmonelose Animal/microbiologia , Salmonella typhimurium/genética , Virulência/genética
17.
Poult Sci ; 100(2): 760-764, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518130

RESUMO

The aim of the present study was to evaluate the effects of quantitative feed restriction (FR) in fast-, medium-, and slow-growing meat-type male and female chickens on their growth, feed consumption, economic efficiency, carcass composition, and gastrointestinal microbiota. In the experiment, fast-growing Ross 308, medium-growing Hubbard JA 757 and slow-growing ISA Dual chickens of both sexes were exposed to quantitative FR between 14 and 21 d of age. During the FR, restricted chickens received 70% of the amount of feed consumed by the ad libitum (AL) group. Live weight at the end of the experiment was affected by genotype (P < 0.001), sex (P < 0.001), feeding regime (P < 0.001), and their interaction (P < 0.001). The highest final weight was in AL and FR ISA Dual males and the lowest was in AL and FR females of the same genotype. A similar tendency was observed in daily weight gain and feed intake. Carcass traits were predominantly affected by genotype. However, interactions of genotype, sex, and feeding regime were observed in thigh (P < 0.001) and abdominal fat (P < 0.001) proportions. Concerning gastrointestinal microbiota, only Escherichia coli was affected by genotype. Feed restriction in slow-growing dual-purpose chickens might improve economic potential; however, further research is needed to reveal the involvement of variable processes, which are unclear and affect production.


Assuntos
Galinhas/crescimento & desenvolvimento , Dieta/veterinária , Genótipo , Microbiota , Ração Animal/análise , Animais , Peso Corporal , Galinhas/classificação , Galinhas/genética , Galinhas/microbiologia , Feminino , Masculino , Carne/análise , Fatores Sexuais
18.
Poult Sci ; 100(3): 100961, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33518318

RESUMO

Salmonella is one of the common foodborne bacteria, causing 80.3 million illnesses every year worldwide. This study was conducted to isolate and identify Salmonella enterica serovars from poultry samples responsible for causing foodborne poisoning in the Mississippi area, United States. A total of 55 S. enterica serovars-Enteritidis (6), Oranienburg (1), Schwarzengrund (8), Heidelberg (4), Kentucky (22), 4, [5], 12:i:- (1), Montevideo (2), Infantis (9), and multi serotypes (2)-were isolated from approximately 110 poultry samples. Through pulsed-field gel electrophoresis (PFGE) analysis, 8 to 13 bands were obtained. The profiles showed >90% similarity in strains within the same type. Consequently, PFGE could be a useful tool to determine chromosomal similarity (clonality of strains) that can be used to trace down epidemiologic sources and geographical origins of Salmonella.


Assuntos
Galinhas , Eletroforese em Gel de Campo Pulsado , Salmonella enterica , Animais , Galinhas/microbiologia , Eletroforese em Gel de Campo Pulsado/veterinária , Carne/microbiologia , Mississippi , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella enterica/genética , Salmonella enterica/isolamento & purificação
19.
Poult Sci ; 100(2): 1008-1015, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518059

RESUMO

A large number of antimicrobials are used for the treatment of bacterial infections, and the emergence of antimicrobial-resistant Escherichia coli (E. coli) in livestock and the transfer of resistant isolates to humans poses a serious potential risk to public health. In particular, broiler parent stock produce thousands of eggs for commercial broiler chickens and can transfer antimicrobial-resistant bacteria and drug-resistance genes to chicks. This study was conducted to investigate the prevalence and characteristics of third-generation cephalosporin-resistant and extended-spectrum ß-lactamases (ESBL)-producing E. coli isolated from the broiler parent stock in Korea. Among 51 cefotaxime-resistant E. coli isolates, 45 (88.2%) isolates were identified as multidrug resistant and 21 isolates showed phenotypic and genotypic characteristics of CTX-M-producing E. coli. The CTX-M genes CTX-M-14, CTX-M-15, CTX-M-1, and CTX-M-1 were detected in 10, 7, 3, and 1 isolates, respectively. ISEcp1 or IS26 + ISEcp1 were identified upstream of all CTX-M-type genes, and orf477 and IS903 were detected downstream of 9 and 10 CTX-M-type genes, respectively. Thirteen (61.9%) of the 21 CTX-M-producing E. coli isolates harbored class 1 integrons with 4 different gene cassette arrangements. Among the plasmid replicons, CTX-M-1 was located on I1, F, and FIB; CTX-M-14 on F and FII; CTX-M-15 on FII, FIA, and FIB; and CTX-M-65 on FIB. This is the first study to investigate the presence and distribution of third-generation cephalosporin-resistant and CTX-M-producing E. coli isolated from the broiler parent stock level in Korea, and the results indicate that comprehensive surveillance and persistent monitoring systems in broiler parent stock farms are necessary to prevent the dissemination of resistant isolates.


Assuntos
Galinhas/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli/metabolismo , Doenças das Aves Domésticas/microbiologia , Animais , Antibacterianos/farmacologia , Cefotaxima/farmacologia , Resistência Microbiana a Medicamentos , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Óvulo , Doenças das Aves Domésticas/epidemiologia , República da Coreia/epidemiologia , beta-Lactamases/genética
20.
Poult Sci ; 100(2): 1016-1023, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33518060

RESUMO

Salmonella is a major zoonotic foodborne pathogen that persists on poultry farms worldwide. The present study aimed to survey the prevalence of Salmonella and antimicrobial resistance of Salmonella enterica serovar Enteritidis (S. Enteritidis) recovered from broiler chickens in Shandong Province, China. A total of 280 Salmonella isolates were identified from 923 broiler chicken samples between 2013 and 2018. Among the isolates, S. Enteritidis (n = 128, 45.7%) was the predominant serovar, and high antimicrobial resistance rates to piperacillin (PIP) (n = 123, 96.1%), ampicillin (AM) (n = 122, 95.3%), nitrofurantoin (FT) (n = 106, 96.1%), and tetracycline (TE) (n = 93, 72.7%) were observed in S. Enteritidis. A total of 96 (75.0%) S. Enteritidis isolates presented with multidrug resistance, the most frequent of which were the combination of AM, PIP, TE, and FT. Resistance to fluoroquinolone tended to increase during 2013 to 2018. Our findings provide important and updated information about the baseline antimicrobial-resistant data for food safety and a risk assessment of S. Enteritidis from broiler chickens in Shandong Province and will be helpful for future surveillance activities to ensure the safety of the chicken supply.


Assuntos
Antibacterianos/farmacologia , Galinhas/microbiologia , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella enteritidis/efeitos dos fármacos , Animais , Ceco/microbiologia , China/epidemiologia , Farmacorresistência Bacteriana Múltipla , Testes de Sensibilidade Microbiana/veterinária , Doenças das Aves Domésticas/epidemiologia , Prevalência , Salmonelose Animal/epidemiologia , Salmonella enteritidis/classificação , Salmonella enteritidis/isolamento & purificação , Sorogrupo
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