RESUMO
The intestinal microbiota has important functions that contribute to host health. The compositional dynamics of microbial communities are affected by many factors, including diet and presence of pathogens. In contrast to humans and domestic mammals, the composition and seasonal dynamics of intestinal microbiota of wildlife species remain comparatively understudied. White-tailed deer (Odocoileus virginianus) is an ecologically and economically important wildlife species that inhabits agricultural ecosystems and is known to be a reservoir of enteric pathogens. Nevertheless, there is a lack of knowledge of white-tailed deer intestinal microbiota diversity and taxonomic composition. This study's first objective was to characterize and compare the intestinal microbiota of 66 fecal samples from white-tailed deer collected during two sampling periods (March and June) using 16S rDNA pyrosequencing. Associations between community diversity and composition and factors including season, sex, host genetic relatedness, and spatial location were quantified. Results revealed that white-tailed deer intestinal microbiota was predominantly comprised of phyla Firmicutes and Proteobacteria, whose relative frequencies varied significantly between sampling periods. The second objective was to examine the associations between the presence of Escherichia coli and Salmonella, and microbiota composition and diversity. Results indicated that relative abundance of some microbial taxa varied when a pathogen was present. This study provides insights into microbial compositional dynamics of a wildlife species inhabiting coupled natural and agricultural landscapes. Data focus attention on the high prevalence of Proteobacteria particularly during the summer and highlight the need for future research regarding the role of white-tailed deer as a natural pathogen reservoir in agroecosystems.
Assuntos
Cervos/microbiologia , Microbioma Gastrointestinal , Proteobactérias/isolamento & purificação , Animais , Fezes/microbiologia , Firmicutes/classificação , Firmicutes/isolamento & purificação , Proteobactérias/classificação , RNA Ribossômico 16S/genética , Estações do AnoRESUMO
UNLABELLED: Shiga toxin-producing Escherichia coli (STEC) is an important foodborne pathogen that can cause hemorrhagic colitis and hemolytic-uremic syndrome. Cattle are the primary reservoir for STEC, and food or water contaminated with cattle feces is the most common source of infections in humans. Consequently, we conducted a cross-sectional study of 1,096 cattle in six dairy herds (n = 718 animals) and five beef herds (n = 378 animals) in the summers of 2011 and 2012 to identify epidemiological factors associated with shedding. Fecal samples were obtained from each animal and cultured for STEC. Multivariate analyses were performed to identify risk factors associated with STEC positivity. The prevalence of STEC was higher in beef cattle (21%) than dairy cattle (13%) (odds ratio [OR], 1.76; 95% confidence interval [CI], 1.25, 2.47), with considerable variation occurring across herds (range, 6% to 54%). Dairy cattle were significantly more likely to shed STEC when the average temperature was >28.9°C 1 to 5 days prior to sampling (OR, 2.5; 95% CI, 1.25, 4.91), during their first lactation (OR, 1.8; 95% CI, 1.1, 2.8), and when they were <30 days in milk (OR, 3.9; 95% CI, 2.1, 7.2). These data suggest that the stress or the negative energy balance associated with lactation may result in increased STEC shedding frequencies in Michigan during the warm summer months. Future prevention strategies aimed at reducing stress during lactation or isolating high-risk animals could be implemented to reduce herd-level shedding levels and avoid transmission of STEC to susceptible animals and people. IMPORTANCE: STEC shedding frequencies vary considerably across cattle herds in Michigan, and the shedding frequency of strains belonging to non-O157 serotypes far exceeds the shedding frequency of O157 strains, which is congruent with human infections in the state. Dairy cattle sampled at higher temperatures, in their first lactation, and early in the milk production stage were significantly more likely to shed STEC, which could be due to stress or a negative energy balance. Future studies should focus on the isolation of high-risk animals to decrease herd shedding levels and the potential for contamination of the food supply.
Assuntos
Derrame de Bactérias , Doenças dos Bovinos/epidemiologia , Infecções por Escherichia coli/veterinária , Síndrome Hemolítico-Urêmica/veterinária , Escherichia coli Shiga Toxigênica/fisiologia , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Estudos Transversais , Indústria de Laticínios , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Feminino , Síndrome Hemolítico-Urêmica/epidemiologia , Síndrome Hemolítico-Urêmica/microbiologia , Michigan/epidemiologia , PrevalênciaRESUMO
Salmonella enterica (nontyphoidal) is one of the major causes of foodborne diseases in the United States and worldwide. Molecular typing methods are significant tools used to better understand the transmission and ecology of Salmonella in order to implement pre-harvest control measures. The objectives of this study were to describe the Salmonella genotypes, the distribution of isolate subtypes from different ecological niches (i.e., barn environment, nursery, and individual pigs) and their evolution over time in a longitudinal study conducted in three finishing sites (housing pigs from 10 weeks of age until slaughter at 24-26 weeks of age). Among the 107 Salmonella isolates submitted for pulsed-field gel electrophoresis (PFGE) analysis, there were 25 distinct subtypes. PFGE genotyping results were consistent with the serotype findings. A large number of distinguishable PFGE patterns (i.e., within the same serovar) were observed and different combinations of subtypes were identified within and across sites and cohorts. New subtypes may result of the introduction of new strains, genetic changes, or ongoing transmission of evolved strains within the production system. The same subtypes were detected intermittently during the study period, which suggests the persistence of indistinguishable subtypes in this production system. In addition, this study suggests persistence of the same subtype over several cohorts of pigs and potential residual contamination from the barn. Factors affecting adaptation and transmission of Salmonella within and among ecological systems (e.g., finishing pigs, nursery, and environment) should be further investigated. Understanding genotypic diversity of Salmonella in different ecological niches during pre-harvest may contribute to the development of more targeted and cost effective control programs during nursery and finishing phases.
Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Fenômenos Fisiológicos Bacterianos , Genes Bacterianos , Variação Genética , Salmonelose Animal/microbiologia , Salmonella/genética , Doenças dos Suínos/microbiologia , Criação de Animais Domésticos , Animais , Animais Recém-Nascidos , Eletroforese em Gel de Campo Pulsado/veterinária , Microbiologia Ambiental , Fezes/microbiologia , Técnicas de Genotipagem/veterinária , Meio-Oeste dos Estados Unidos , Tipagem Molecular/veterinária , Salmonella/classificação , Salmonella/crescimento & desenvolvimento , Salmonella/isolamento & purificação , Salmonelose Animal/diagnóstico , Sorotipagem/veterinária , Análise Espaço-Temporal , Sus scrofa , Suínos , Doenças dos Suínos/diagnósticoRESUMO
Shiga toxin-producing Escherichia coli (STEC) infections are a critical public health concern because they can cause severe clinical outcomes, such as hemolytic uremic syndrome, in humans. Determining the presence or absence of virulence genes is essential in assessing the potential pathogenicity of STEC strains. Currently, there is limited information about the virulence genes carried by swine STEC strains; therefore, this study was conducted to examine the presence and absence of 69 virulence genes in STEC strains recovered previously from finishing swine in a longitudinal study. A subset of STEC strains was analyzed by pulsed-field gel electrophoresis (PFGE) to examine their genetic relatedness. Swine STEC strains (n = 150) were analyzed by the use of a high-throughput real-time PCR array system, which included 69 virulence gene targets. Three major pathotypes consisted of 16 different combinations of virulence gene profiles, and serotypes were determined in the swine STEC strains. The majority of the swine STEC strains (n = 120) belonged to serotype O59:H21 and carried the same virulence gene profile, which consisted of 9 virulence genes: stx2e, iha, ecs1763, lpfAO113, estIa (STa), ehaA, paa, terE, and ureD. The eae, nleF, and nleH1-2 genes were detected in one swine STEC strain (O49:H21). Other genes encoding adhesins, including iha, were identified (n = 149). The PFGE results demonstrated that swine STEC strains from pigs raised in the same finishing barn were closely related. Our results revealed diverse virulence gene contents among the members of the swine STEC population and enhance understanding of the dynamics of transmission of STEC strains among pigs housed in the same barn.
Assuntos
Escherichia coli Shiga Toxigênica/genética , Escherichia coli Shiga Toxigênica/patogenicidade , Animais , Eletroforese em Gel de Campo Pulsado , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/transmissão , Infecções por Escherichia coli/veterinária , Abrigo para Animais , Reação em Cadeia da Polimerase em Tempo Real , Sorogrupo , Escherichia coli Shiga Toxigênica/classificação , Suínos/microbiologia , Doenças dos Suínos/microbiologia , Doenças dos Suínos/transmissão , Virulência/genéticaRESUMO
We investigated the implied health benefits of retail chicken breast labeled as "organic" or "antibiotic-free" when compared to conventional products based on frequency of contamination by Salmonella spp., Campylobacter spp., and coliform bacteria resistant to fluoroquinolones, extended-spectrum cephalosporins, or carbapenems. We purchased 231 prepackaged chicken breasts from 99 grocery stores representing 17 retail chains in Ohio, Michigan, and Pennsylvania from June to September 2012. Ninety-six (41.5%) packages were labeled "antibiotic free" and 40 (17.3%) were labeled "organic," with the remaining 95 (41.1%) making neither label claim. Salmonella were recovered from 56 (24.2%) packages, and the recovery rate was not different between product types. Five percent of packages contained Salmonella carrying the extended-spectrum cephalosporin resistance gene bla(CMY-2), representing 21.4% of Salmonella isolates. Campylobacter spp. were recovered from 10.8% of packages, with observed recovery rates similar for the three product types. Using selective media, we recovered Escherichia coli harboring bla(CMY-2) from over half (53.7%) of packages, with similar recovery rates for all product types. In addition, we recovered E. coli carrying bla(CTX-M) from 6.9% of packages, and E. coli with QRDR mutations from 8.2% of packages. Fluoroquinolone-resistant E. coli recovered using selective media were more common (p<0.05) in conventional (18.9%) compared to organic (0) and antibiotic-free (2.1%) packages. Our results indicate that, regardless of product type, fresh retail chicken breast is commonly contaminated with enteric pathogens associated with foodborne illness and commensal bacteria harboring genes conferring resistance to critically important antimicrobial drugs.
Assuntos
Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/isolamento & purificação , Contaminação de Alimentos/análise , Rotulagem de Alimentos , Alimentos Orgânicos/microbiologia , Carne/microbiologia , Animais , Antibacterianos/farmacologia , Campylobacter/genética , Campylobacter/isolamento & purificação , Galinhas , Escherichia coli/genética , Microbiologia de Alimentos , Michigan , Testes de Sensibilidade Microbiana , Ohio , Pennsylvania , Salmonella/genética , Salmonella/isolamento & purificação , beta-Lactamases/genéticaRESUMO
We report the recovery of Escherichia coli or Klebsiella pneumoniae containing the extended-spectrum ß-lactamase gene bla(CTX-M) from 24 of 1,495 (1.6%) swine fecal samples in 8 of 50 (16%) finishing barns located in 5 U.S. states. We did not detect an association between antimicrobial use and recovery of bla(CTX-M).
Assuntos
Antibacterianos/administração & dosagem , Cefalosporinase/genética , Escherichia coli/enzimologia , Fezes/microbiologia , Klebsiella pneumoniae/enzimologia , Suínos/microbiologia , Animais , Cefalosporinase/metabolismo , Dieta/métodos , Escherichia coli/isolamento & purificação , Klebsiella pneumoniae/isolamento & purificação , Estados UnidosRESUMO
BACKGROUND: The threat of a global pandemic posed by outbreaks of influenza H5N1 (1997) and Severe Acute Respiratory Syndrome (SARS, 2002), both diseases of zoonotic origin, provoked interest in improving early warning systems and reinforced the need for combining data from different sources. It led to the use of search query data from search engines such as Google and Yahoo! as an indicator of when and where influenza was occurring. This methodology has subsequently been extended to other diseases and has led to experimentation with new types of social media for disease surveillance. OBJECTIVE: The objective of this scoping review was to formally assess the current state of knowledge regarding the use of search queries and social media for disease surveillance in order to inform future work on early detection and more effective mitigation of the effects of foodborne illness. METHODS: Structured scoping review methods were used to identify, characterize, and evaluate all published primary research, expert review, and commentary articles regarding the use of social media in surveillance of infectious diseases from 2002-2011. RESULTS: Thirty-two primary research articles and 19 reviews and case studies were identified as relevant. Most relevant citations were peer-reviewed journal articles (29/32, 91%) published in 2010-11 (28/32, 88%) and reported use of a Google program for surveillance of influenza. Only four primary research articles investigated social media in the context of foodborne disease or gastroenteritis. Most authors (21/32 articles, 66%) reported that social media-based surveillance had comparable performance when compared to an existing surveillance program. The most commonly reported strengths of social media surveillance programs included their effectiveness (21/32, 66%) and rapid detection of disease (21/32, 66%). The most commonly reported weaknesses were the potential for false positive (16/32, 50%) and false negative (11/32, 34%) results. Most authors (24/32, 75%) recommended that social media programs should primarily be used to support existing surveillance programs. CONCLUSIONS: The use of search queries and social media for disease surveillance are relatively recent phenomena (first reported in 2006). Both the tools themselves and the methodologies for exploiting them are evolving over time. While their accuracy, speed, and cost compare favorably with existing surveillance systems, the primary challenge is to refine the data signal by reducing surrounding noise. Further developments in digital disease surveillance have the potential to improve sensitivity and specificity, passively through advances in machine learning and actively through engagement of users. Adoption, even as supporting systems for existing surveillance, will entail a high level of familiarity with the tools and collaboration across jurisdictions.
Assuntos
Surtos de Doenças , Inovação Organizacional , Vigilância da População , Mídias Sociais , HumanosRESUMO
Quantification of Salmonella in asymptomatic pigs can be used to institute control measures and to assess risk of carcass contamination during slaughter. The objective of this study was to quantify the fecal concentration of Salmonella in naturally infected pigs. Individual fecal samples (positive [n=443], negative [n=1225] determined by microbiological culture) were submitted for direct quantitative real-time polymerase chain reaction (q-PCR). Direct q-PCR categorized 99.6% (1220/1225) of culture negative samples as negative. For culture positive samples, 15.4% (68/443) were detected by q-PCR, but only 3.4% (15/443) were within the direct q-PCR quantifiable range (≥ 10(3) colony-forming units [CFU]/g of feces). Of these latter samples, the concentration range was 1.06 × 10(3) to 1.73 × 10(6) CFU/g feces. Of the 15 samples with high Salmonella concentrations, seven were collected from one pig and three samples were collected from its penmates. Direct q-PCR may be an alternative to traditional culture-dependent methods for detection of pigs with high fecal concentrations of Salmonella, but not for detection of pigs shedding low concentrations of Salmonella, which represented the majority of pigs in this study. When high shedding was detected it was clustered within a single pig and its penmates. These data contribute to quantitative risk assessments of the association between concentrations of Salmonella shed by pigs during the finishing phase and risk of carcass contamination at slaughter.
Assuntos
Fezes/microbiologia , Salmonelose Animal/microbiologia , Salmonella/isolamento & purificação , Doenças dos Suínos/microbiologia , Animais , Contagem de Colônia Microbiana/veterinária , Reação em Cadeia da Polimerase em Tempo Real , Salmonella/crescimento & desenvolvimento , SuínosRESUMO
Swine are the primary reservoir for foodborne illness associated with Yersinia enterocolitica. The use of antimicrobials in animal agriculture has been hypothesized as having a potential role in the increase in prevalence of zoonotic pathogens. The objective of this study was to compare the frequency of Y. enterocolitica fecal shedding in swine reared on farms with conventional antimicrobial use policies to farms that were antimicrobial free (ABF). Swine farms were selected from three regions in the United States. In each region, farms were categorized based on antimicrobial use policy. Fecal samples were collected from pigs on-farm within 48 h of harvest. The overall proportion of Y. enterocolitica and ail-harboring Y. enterocolitica-positive pigs was 10.9% and 4.0%, respectively. There were increased odds (odds ratio [OR] 6.8, 95% confidence interval [CI] 3.46-13.28) for a pig to be Y. enterocolitica positive if it was reared on an ABF farm as compared to a conventional farm. There was no significant association between farm antimicrobial use policy and isolation of an ail-harboring Y. enterocolitica from an individual pig (OR 1.8, 95% CI 0.90-3.61). The association of antimicrobial use policy with Y. enterocolitica shedding in feces should be interpreted cautiously, as antimicrobial use cannot be separated from other management factors (e.g., confinement or outdoor housing), which may be associated with risk of Y. enterocolitica in swine.
Assuntos
Criação de Animais Domésticos/métodos , Anti-Infecciosos/administração & dosagem , Sus scrofa/microbiologia , Yersinia enterocolitica/crescimento & desenvolvimento , Animais , Proteínas da Membrana Bacteriana Externa/genética , Proteínas da Membrana Bacteriana Externa/metabolismo , Derrame de Bactérias/efeitos dos fármacos , Biomarcadores/metabolismo , Fezes/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Humanos , Meio-Oeste dos Estados Unidos , Tipagem Molecular , North Carolina , Sorotipagem , Yersiniose/prevenção & controle , Yersinia enterocolitica/classificação , Yersinia enterocolitica/isolamento & purificação , Yersinia enterocolitica/metabolismoRESUMO
Yersinia enterocolitica is an important foodborne pathogen, and pigs are recognized as a major reservoir and potential source of pathogenic strains to humans. A total of 172 Y. enterocolitica recovered from conventional and antimicrobial-free pig production systems from different geographic regions (North Carolina, Ohio, Michigan, Wisconsin, and Iowa) were investigated to determine their pathogenic significance to humans. Phenotypic and genotypic diversity of the isolates was assessed using antibiogram, serogrouping, and amplified fragment length polymorphism (AFLP). Carriage of chromosomal and plasmid-borne virulence genes were investigated using polymerase chain reaction. A total of 12 antimicrobial resistance patterns were identified. More than two-thirds (67.4%) of Y. enterocolitica were pan-susceptible, and 27.9% were resistant against ß-lactams. The most predominant serogroup was O:3 (43%), followed by O:5 (25.6%) and O:9 (4.1%). Twenty-two of 172 (12.8%) isolates were found to carry Yersinia adhesion A (yadA), a virulence gene encoded on the Yersinia virulence plasmid. Sixty-nine (40.1%) isolates were found to carry ail gene. The ystA and ystB genes were detected in 77% and 26.2% of the strains, respectively. AFLP genotyping of isolates showed wide genotypic diversity and were grouped into nine clades with an overall genotypic similarity of 66.8-99.3%. AFLP analysis revealed that isolates from the same production system showed clonal relatedness, while more than one genotype of Y. enterocolitica circulates within a farm.
Assuntos
Doenças Transmitidas por Alimentos/microbiologia , Variação Genética , Doenças dos Suínos/microbiologia , Fatores de Virulência/genética , Yersiniose/microbiologia , Yersinia enterocolitica/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , Proteínas de Bactérias/genética , Cromossomos Bacterianos/genética , Análise por Conglomerados , DNA Bacteriano/genética , Reservatórios de Doenças , Farmacorresistência Bacteriana , Fezes/microbiologia , Genótipo , Humanos , Meio-Oeste dos Estados Unidos , North Carolina , Fenótipo , Plasmídeos/genética , Sorotipagem , Suínos , Yersiniose/transmissão , Yersinia enterocolitica/isolamento & purificação , Yersinia enterocolitica/patogenicidade , Zoonoses , beta-Lactamases/genéticaRESUMO
The objective of this study was to determine persistence of clonal strains from farm to retail by assessing the clonal relatedness of Campylobacter coli isolated on farm, peri-harvest, and at processing from 11 individually identified pigs. Phenotypic (antimicrobial susceptibility) and genotypic (pulsed field gel electrophoresis [PFGE] and multi-locus sequence typing [MLST]) characterization of isolates was conducted. There was high genetic diversity of Campylobacter isolates from on-farm fecal samples. Campylobacter isolates from farm, post-evisceration, hide, and carcass samples showed similar phenotypes and belonged to the same genotypic clusters based on PFGE and sequence types (STs) based on MLST. Five STs that have not been previously reported were identified (ST-4083, ST-4084, ST-4085, ST-4086, ST-4087). Despite high genotypic diversity of C. coli on farm, retail meat products were consistently contaminated with isolates of the same STs, particularly ST854 and ST1056, as isolates collected from previous stages confirming persistence of strains from pre- to post-harvest.
Assuntos
Antibacterianos/farmacologia , Campylobacter coli/efeitos dos fármacos , Farmacorresistência Bacteriana , Variação Genética , Carne/microbiologia , Sus scrofa/microbiologia , Animais , Campylobacter coli/classificação , Campylobacter coli/genética , Campylobacter coli/isolamento & purificação , Farmacorresistência Bacteriana Múltipla , Eletroforese em Gel de Campo Pulsado , Microbiologia Ambiental , Fezes/microbiologia , Doenças Transmitidas por Alimentos/prevenção & controle , Tipagem de Sequências Multilocus , Filogenia , Reto/microbiologia , Estações do Ano , Pele/microbiologia , Estados UnidosRESUMO
Salmonella and Campylobacter cause a significant number of human illnesses globally, most of which are food related. Cattle can be asymptomatic carriers of both of these pathogens. The objective of this study was to determine the association between the concentration of Salmonella and Campylobacter pre- and postharvest in cattle. Samples were collected from each of 98 individually identified cattle during the periharvest and postharvest period. For each animal, four different phases were sampled: on farm (fecal sample), poststunning and exsanguination (hide sponge and rectal content sample [lairage]), prechilling (carcass sponge), and final product (ground meat). Salmonella and Campylobacter were cultured and quantified at each stage by using the direct dilution and most probable number (MPN) method. Salmonella was not isolated from any sample. The proportion (%) of samples that were Campylobacter positive was 77, 82, 97, 55, and 12 for farm, rectal content, hide, carcass, and meat samples respectively. The mean Campylobacter concentration for each sample was as follows: fecal sample from farm, 3.7×10(4) cfu/g; rectal content sample from lairage, 1.6×10(5) cfu/g; hide sponge, 0.9 cfu/cm(2); carcass sponge, 8.7 cfu/half carcass; and meat, 1.1 cfu/g. There were no associations between Campylobacter concentrations for any two sample types. This lack of association could indicate that there is an environmental reservoir that can contaminate the final meat product, or since the majority of animals were positive entering the slaughter process, that the process itself reduces the load of Campylobacter regardless of the initial concentration. In addition, contamination of beef may be more strongly associated with periharvest practices than animal carriage rates.
Assuntos
Infecções por Campylobacter/veterinária , Campylobacter/isolamento & purificação , Doenças dos Bovinos/epidemiologia , Carne/microbiologia , Salmonelose Animal/epidemiologia , Salmonella/isolamento & purificação , Matadouros , Animais , Campylobacter/genética , Campylobacter/crescimento & desenvolvimento , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Bovinos , Doenças dos Bovinos/microbiologia , Contagem de Colônia Microbiana , Fezes/microbiologia , Microbiologia de Alimentos , Genes Bacterianos/genética , Humanos , Masculino , Ohio/epidemiologia , Salmonella/genética , Salmonella/crescimento & desenvolvimento , Salmonelose Animal/microbiologiaRESUMO
We estimated the proportion of retail beef and pork products containing bla(CMY)-mediated third-generation cephalosporin resistance in commensal Escherichia coli and Salmonella enterica. Samples were obtained from 50 grocery stores located in two U.S. states. From each store, 20 fresh meat products were purchased, including 7 packages of ground beef, 3 packages of beef steak, 6 packages of pork chops, and 4 packages of pork ribs. The resulting 1000 packages of fresh meat product were individually screened for the presence of E. coli or Salmonella harboring bla(CMY). Over 8% of all retail meat packages contained E. coli with bla(CMY), whereas 4% contained Salmonella and only 0.5% contained Salmonella with bla(CMY). Retail pork products more frequently yielded E. coli with bla(CMY) than did beef products (12.2% vs. 4.0%; p = 0.06). Salmonella were also recovered more frequently from pork than beef (5.8% vs. 2.4%; p < 0.01). In addition, all five Salmonella isolates with bla(CMY) were recovered from pork products. Our data suggest that enteric bacteria carrying bla(CMY) are frequently present in fresh retail meat products. However, we did not quantify the number of resistant bacteria present in these products, which makes the public health implications of this result unclear.
Assuntos
Resistência às Cefalosporinas/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Carne/microbiologia , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/genética , beta-Lactamases/genética , Animais , Bovinos , Escherichia coli/isolamento & purificação , Microbiologia de Alimentos , Salmonella enterica/isolamento & purificação , Sus scrofa , Estados Unidos , beta-Lactamases/metabolismoRESUMO
The objective of this study was to investigate the association between ceftiofur use policy in finishing swine barns and recovery of fecal Escherichia coli or Salmonella spp. resistant to ceftriaxone. The study population included 54 finishing swine barns from three companies located in North Carolina. The barns were each classified according to their reported therapeutic ceftiofur use rates of "Rare," "Moderate," and "Common." Fecal samples from the barns were cultured for the presence of E. coli and Salmonella spp. resistant to ceftriaxone using selective media designed to recover rare organisms expressing the AmpC ß-lactamase phenotype. A total of 1899 swine fecal samples yielded 1193 E. coli (63%) resistant to ceftriaxone. Recovery rates by ceftiofur use classification were 45% for Rare, 73% for Moderate, and 68% Common ceftiofur use groups. Barns reporting Rare ceftiofur use had a lower odds of recovery of E. coli (OR=0.32; p<0.001) resistant to ceftriaxone compared to Common use barns. The overall Salmonella spp. prevalence was 63.8% (n=714). Of these, 65 Salmonella were resistant to ceftriaxone with the highest rate (6%) found in the Common ceftiofur use group, followed by Rare (4.1%) and Moderate (0.15%). The odds of recovery of Salmonella resistant to ceftriaxone were similar for barns with ceftiofur use classified as Rare and Common. Samples from barns with ceftiofur use classified as Moderate had a lower odds (OR=0.02; p<0.01) of recovery of Salmonella resistant to ceftriaxone than barns classified as Common. Our result is consistent with the hypothesis that the use of ceftiofur in finishing swine barns, beyond its rare application, may influence the recovery of enteric E. coli with resistance to cephalosporin drugs, although other unmeasured factors appear to be important in the recovery of cephalosporin-resistant Salmonella. The dissemination of enteric bacteria with resistance to cephalosporins has the potential to impact both veterinary and human therapeutic treatment options.
Assuntos
Antibacterianos/farmacologia , Ceftriaxona/farmacologia , Cefalosporinas/farmacologia , Escherichia coli/efeitos dos fármacos , Fezes/microbiologia , Salmonella/efeitos dos fármacos , Animais , Resistência às Cefalosporinas , Estudos Transversais , Farmacorresistência Bacteriana , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Humanos , Modelos Logísticos , Testes de Sensibilidade Microbiana , North Carolina , Salmonella/isolamento & purificação , Salmonelose Animal/microbiologia , Suínos , Doenças dos Suínos/microbiologiaRESUMO
We conducted a study to compare the prevalence and antimicrobial resistance profile of Campylobacter isolated from 34 farm-slaughter pair cohorts of pigs raised in conventional and antimicrobial-free (ABF) production systems. Isolates originated from four different states of two geographic regions (region 1--Ohio and Michigan; region 2--Wisconsin and Iowa). A total of 838 fecal and 1173 carcass samples were examined. Campylobacter isolates were speciated using multiplex polymerase chain reaction targeting ceuE and hipO genes. The minimum inhibitory concentration was determined using agar dilution to a panel of six antimicrobials: chloramphenicol, erythromycin, gentamicin, ciprofloxacin, nalidixic acid, and tetracycline. Campylobacter spp. was isolated from 472 of 838 pigs (56.3%). Campylobacter prevalence did not vary significantly based on production system (conventional [58.9%] and ABF [53.7%], odds ratio [OR] 1.4, 95% confidence interval [CI] 0.8-2.6, p = 0.24) or geographic region (region 1 [54.1%] and region 2 [58.2%], OR 1.02, 95% CI 0.6-1.9, p = 0.92). At slaughter plant, Campylobacter prevalence varied based on processing stages (19.4% at pre-evisceration, 25.3% at postevisceration, and 3.2% at postchill). Resistance was common to tetracycline (64.5%), erythromycin (47.9%), and nalidixic acid (23.5%). Campylobacter isolates from conventional production systems were more likely to be erythromycin resistant than from ABF (OR 3.2, 95% CI 1.4-7.2, p = 0.01). The proportion of ciprofloxacin-resistant Campylobacter coli isolates were 3.7% and 1.2% from ABF and conventional production systems, respectively. Thirty-seven out of 1257 C. coli (2.9%) were resistant to both erythromycin and ciprofloxacin, drugs of choice for treatment of invasive human campylobacteriosis. The finding of ciprofloxacin resistance, particularly from ABF herds, has significant implications on the potential role of risk factors other than mere antimicrobial use for production purposes.
Assuntos
Antibacterianos/farmacologia , Infecções por Campylobacter/veterinária , Campylobacter/efeitos dos fármacos , Campylobacter/isolamento & purificação , Doenças dos Suínos/microbiologia , Matadouros , Criação de Animais Domésticos , Animais , Antibacterianos/administração & dosagem , Campylobacter/classificação , Infecções por Campylobacter/epidemiologia , Infecções por Campylobacter/microbiologia , Estudos de Coortes , Intervalos de Confiança , Farmacorresistência Bacteriana , Fezes/microbiologia , Great Lakes Region/epidemiologia , Testes de Sensibilidade Microbiana/veterinária , Meio-Oeste dos Estados Unidos/epidemiologia , Reação em Cadeia da Polimerase , Prevalência , Fatores de Risco , Suínos , Doenças dos Suínos/epidemiologiaRESUMO
The bla(CMY-2) family of the ampC beta-lactamase genes confer broad-spectrum resistance to beta-lactam antimicrobials, including ceftriaxone and ceftiofur, as well as to beta-lactamase inhibitors, such as clavulanic acid. Organisms with the bla(CMY-2) phenotype have been recovered from the environment and from retail meat products, posing a potential public health risk. The objectives of this study were to sequence the bla(CMY-2) gene from Escherichia coli and Salmonella enterica from multiple sources that had a reduced susceptibility to ceftriaxone and to determine the effect of observed mutations in the bla(CMY-2) gene on the antimicrobial resistance phenotype (spectrum and minimum inhibitory concentration/susceptibility patterns) of the isolates. The bla(CMY-2) genes from 52 bacterial isolates were sequenced for this study. Sixty-two percent (32/52) were E. coli and 38% (20/52) were S. enterica. Of the 32 E. coli isolates, 30 were found to carry a beta-lactamase gene that was 100% homologous to bla(CMY-2). One of the E. coli isolates was found to contain a gene that was 90% homologous to bla(CMY-2). This isolate also had lower minimum inhibitory concentrations to tetracyclines, streptomycin, and the sulfonamide antimicrobials than are commonly expected for isolates containing the bla(CMY-2). Of the 20 genes obtained from Salmonella isolates, 8 (40%) were found to be homologous to bla(CMY-2), with no altered susceptibility phenotypes observed.
Assuntos
Proteínas de Bactérias/genética , Resistência às Cefalosporinas/genética , Farmacorresistência Bacteriana Múltipla/genética , Escherichia coli/genética , Salmonella enterica/genética , beta-Lactamases/genética , Alelos , Animais , Animais Domésticos/microbiologia , DNA Bacteriano/química , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Fezes/microbiologia , Contaminação de Alimentos/prevenção & controle , Estudos de Associação Genética , Humanos , Carne/microbiologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/isolamento & purificação , Análise de Sequência de DNA , Especificidade da Espécie , Estados UnidosRESUMO
OBJECTIVE: To estimate the relationship between therapeutic use of ceftiofur and recovery of Escherichia coli and Salmonella spp with reduced susceptibility to ceftriaxone from feces of dairy cattle. ANIMALS: 3,840 mature dairy cows on 50 dairy herds in Ohio. Procedures-Fecal samples were obtained from up to 100 mature dairy cows on each farm. Samples were screened for E coli and Salmonella spp with reduced susceptibility to ceftriaxone by use of selective media. RESULTS: E coli with reduced susceptibility to ceftriaxone was recovered from 92% (46/50) of the herds and 60.9% (2,338/3,840) of cows. Salmonella spp were recovered from 44% (22/50) of the herds and 9.9% (382/3,840) of cows. No association was found between ceftiofur use and recovery of E coli with reduced susceptibility to ceftriaxone at the herd level. However, recovery of E coli with reduced susceptibility to ceftriaxone was more likely from cows in herds in which Salmonella spp were also recovered on the day of collection (odds ratio, 24.96; 95% confidence interval, 3.17 to 196.68) than from herds in which Salmonella spp were not recovered. Odds of recovery of E coli with reduced susceptibility to ceftriaxone from an individual cow increased 62% (odds ratio, 1.62; 95% confidence interval, 1.16 to 2.25) for every 454-kg increase in herd milk production. CONCLUSIONS AND CLINICAL RELEVANCE: No evidence was found that the use of ceftiofur on dairy farms increases the prevalence or dissemination of Salmonella spp or E coli with reduced susceptibility to ceftriaxone.
Assuntos
Ceftriaxona/farmacologia , Farmacorresistência Bacteriana , Escherichia coli/efeitos dos fármacos , Fezes/microbiologia , Salmonella enterica/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Bovinos , Cefalosporinas/farmacologia , Escherichia coli/isolamento & purificação , Feminino , Salmonella enterica/isolamento & purificaçãoRESUMO
There has been a growing niche-market, outdoor, antimicrobial-free (ABF) swine production system in the last few years prompted by consumers' demand for a more "natural" pork product. The impact of such production systems on reemergence of current and historically significant swine-associated pathogens has not been determined. The objectives of the current study were to determine and compare Salmonella, Toxoplasma, and Trichinella seropositivity in two swine production systems: outdoor ABF and intensive indoor production systems. These three foodborne pathogens represent those with the highest importance for pork consumption. A total of 675 serum samples from three participating states, Wisconsin, North Carolina, and Ohio, were investigated. We found significantly higher seroprevalence of Salmonella and Toxoplasma from ABF herds (54% and 7%, respectively) than conventional (39% and 1%, respectively) (p = 0.001). Two pigs, both from ABF herds, were found to be seropositive for Trichinella. The results from this preliminary study suggest that all three pathogens were more commonly present in pigs that were reared in an ABF, outdoor, niche-market type of environment than the conventional, indoor-reared herds though there were some geographical variation in Salmonella. This warrants a robust epidemiologic study to determine the role of various risk factors in the two production systems that may lead to persistence of bacterial (Salmonella) pathogens and reemergence of parasites (such as Trichinella) of historical significance.
Assuntos
Criação de Animais Domésticos/métodos , Medição de Risco , Salmonelose Animal/epidemiologia , Doenças dos Suínos/epidemiologia , Toxoplasmose Animal/epidemiologia , Triquinelose/veterinária , Animais , Antibacterianos/administração & dosagem , Anticorpos Antibacterianos/sangue , Anticorpos Anti-Helmínticos/sangue , Anticorpos Antiprotozoários/sangue , Qualidade de Produtos para o Consumidor , Humanos , Carne/microbiologia , Carne/parasitologia , Salmonella/imunologia , Estudos Soroepidemiológicos , Suínos , Toxoplasma/imunologia , Trichinella/imunologia , Triquinelose/epidemiologiaRESUMO
OBJECTIVE: To estimate the efficacy of a commercially available Salmonella enterica subunit vaccine on the subclinical shedding of S enterica in dairy cattle. DESIGN: Randomized, controlled trial. ANIMALS: 175 mature cows on 2 dairy farms with a history of S enterica infection. PROCEDURES: 25% of the mature cows from each herd were systematically randomized to receive an S enterica subunit vaccine following label guidelines. The remaining 75% of cows in each herd served as nonvaccinated controls. Fecal samples were collected from all cows at the time of initial vaccination (day 0), booster vaccination (day 14), 2 weeks following the booster vaccination (day 28), and 10 weeks following the start of the trial (day 70). All samples were processed on the day of collection and cultured for S enterica. RESULTS: 651 fecal samples were obtained over the entire study period. Salmonella enterica was recovered from 46 (7.1%) of the samples. Shedding of S enterica was similar for vaccinated and nonvaccinated control cows on each of the collection dates. CONCLUSIONS AND CLINICAL RELEVANCE: The study revealed no evidence that extralabel vaccination with a commercial subunit S enterica vaccine reduced shedding of S enterica in subclinically infected dairy cows in these herds.