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1.
Vet Microbiol ; 235: 63-70, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282380

RESUMO

Salmonella enterica subsp. enterica serovar Gallinarum biovar Gallinarum (SG) causes fowl typhoid (FT) and substantial economic loss in Korea due to egg drop syndrome and mortality. Despite the extensive use of vaccines, FT still occurs in the field. Therefore, the emergence of more pathogenic SG or the recovered pathogenicity of a vaccine strain has been suspected. SpvB, an ADP-ribosyl transferase, is a major pathogenesis determinant, and the length of the polyproline linker (PPL) of SpvB affects pathogenic potency. SG strains accumulate pseudogenes in their genomes during host adaptation, and pseudogene profiling may provide evolutionary information. In this study, we found that the PPL length of Korean SG isolates varied from 11 to 21 prolines and was longer than that of a live vaccine strain, SG 9R (9 prolines). According to growth competition in chickens, the growth of an SG isolate with a PPL length of 17 prolines exceeded that of an SG isolate with a PPL length of 15 prolines. We investigated the pseudogenes of the field isolates, SG 9R and reference strains in GenBank by resequencing and comparative genomics. The pseudogene profiles of the field isolates were notably different from those of the foreign SG strains, and they were subdivided into 7 pseudogene subgroups. Collectively, the field isolates had gradually evolved by changing PPL length and acquiring additional pseudogenes. Thus, the characterization of PPL length and pseudogene profiling may be useful to understand the molecular evolution of SG and the epidemiology of FT.


Assuntos
Galinhas/microbiologia , Evolução Molecular , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella enterica/genética , ADP Ribose Transferases/genética , Animais , Surtos de Doenças , Ligantes , Peptídeos/genética , Pseudogenes , República da Coreia , Salmonella enterica/isolamento & purificação , Sorogrupo
2.
Rev Inst Med Trop Sao Paulo ; 61: e36, 2019 Jul 22.
Artigo em Inglês | MEDLINE | ID: mdl-31340248

RESUMO

During the last years, Brazilian government control programs have detected an increase of Salmonella Heidelberg in poultry slaughterhouses a condition that poses a threat to human health However, the reasons remain unclear. Differences in genetic virulence profiles may be a possible justification. In addition, effective control of Salmonella is related to an efficient epidemiological surveillance system through genotyping techniques. In this context, the aim of this study was the detection of 24 virulence-associated genes in 126 S. Heidelberg isolates. We classified the isolates into 56 different genetic profiles. None of the isolates presented all the virulence genes. The prevalence of these genes was high in all tested samples as the lowest number of genes detected in one isolate was 10/24. The lpfA and csgA (fimbriae), invA and sivH (TTSS), and msgA and tolC (intracellular survival) genes were present in 100% of the isolates analyzed. Genes encoding effector proteins were detected in the majority of SH isolates. No single isolate had the sefA gene. The pefA gene was found in only four isolates. We have also performed a screening of genes associated with iron metabolism: 88.9% of isolates had the iroN geneand 79.4% the sitC gene . Although all the isolates belong to the same serotype, several genotypic profiles were observed. These findings suggest that there is a diversity of S. Heidelberg isolates in poultry products. The fact that a single predominant profile was not found in this study indicates the presence of variable sources of contamination caused by SH. The detection of genetic profiles of Salmonella strains can be used to determine the virulence patterns of SH isolates.


Assuntos
Doenças das Aves Domésticas/microbiologia , Produtos Avícolas/microbiologia , Salmonelose Animal/microbiologia , Salmonella/genética , Salmonella/patogenicidade , Fatores de Virulência/genética , Virulência/genética , Animais , Microbiologia de Alimentos , Genótipo , Reação em Cadeia da Polimerase
3.
Zoonoses Public Health ; 66(6): 587-596, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31310056

RESUMO

Salmonella enterica is a common food-borne pathogen with occasional multidrug resistance (MDR). Salmonella genomic island (SGI1) is a horizontally transmissible genomic island, containing an MDR gene cluster. All Salmonella serotypes are public health concern, although there is an additional concern associated with those that harbour SGI1. In Iran, there are no data on the presence of SGI1 variants in Salmonella isolates. The present study was conducted to identify MDR- and SGI1-carrying Salmonella strains isolated from various sources and to compare their genetic relatedness between human and animal sources. In total, 242 Salmonella isolates collected from chicken, cattle, and humans from 2008 through 2014 were studied. The isolates were tested for resistance to 14 antimicrobials via the disc diffusion method. They were also tested for the presence of SGI1 variants via PCR, and genetic relatedness was evaluated based on pulsed-field gel electrophoresis (PFGE). Resistance to at least one antimicrobial agent was observed in 132 (54%) Salmonella isolates (n = 242), while more than 40% of the isolates showed MDR. Based on PCR analysis, eight variants of SGI1, including SGI1, SGI1-B, SGI1-C, SGI1-D, SGI1-F, SGI1-I, SGI1-J and SGI1-O, were found in both human and animal isolates. Statistical analysis revealed no significant difference in the prevalence of SGI1 variants between human and animal isolates (p > 0.05). Macrorestriction PFGE analysis of the isolates with the same SGI1 variant and resistance patterns revealed genetic relatedness ranging from 70% to 100% among human and animal isolates. According to our review, this is the first documentation of SGI1 in Salmonella isolates in Iran. The presence of similar SGI1 variants in both humans and animals, along with their related PFGE patterns, suggests that food-producing animals may be a source of MDR Salmonella isolates in Iran.


Assuntos
Doenças dos Bovinos/microbiologia , Ilhas Genômicas/genética , Doenças das Aves Domésticas/microbiologia , Infecções por Salmonella/microbiologia , Salmonella/genética , Animais , Antibacterianos , Bovinos , Galinhas , Farmacorresistência Bacteriana Múltipla , Humanos
4.
Vet Parasitol ; 271: 57-63, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31303205

RESUMO

The poultry red mite, Dermanyssus gallinae, is a blood-feeding ectoparasite that affects egg-laying hens worldwide. Strategies to control this parasite have focused in the use of entomopathogenic fungi, such as Metarhizium anisopliae. However, only a few studies have evaluated the use of Aspergillus oryzae to control D. gallinae and none of them have employed native strains. In the work presented here, a novel entomopathogenic fungus was isolated from a dead D. gallinae. The results of phylogenetic analysis showed 100% similarity between the isolated strain and those of two species, A. oryzae and Aspergillus flavus, and 99.82% similarity with A. parvisclerotigenus, which were in the same branch of the Flavi section of the genus Aspergillus. This entomopathogenic fungus was a non-aflatoxin B1 producer, as shown by the presence of aflatoxin B1 in the conidial infection suspension. Morphological features of fungus in comparison with A. oryzae and A. flavus indicated that the isolated strain belonged to A. oryzae, and was named Aspergillus sp. Dg-1. The pathogenicity of Aspergillus sp. Dg-1 on D. gallinae at different life stages was then assessed under laboratory conditions. The experiments showed that the isolated strain significantly increased the mortality rate in adult mites, up to 24.83 ± 2.25, compared to the mortality rates in the control group, which were 15.17 ± 2.75 (P < 0.05). However, Aspergillus sp. Dg-1 did not have pathogenic effects on the second nymph stage of D. gallinae. Our findings demonstrate that Aspergillus sp. Dg-1 has pathogenic effects on D. gallinae in their adult stage, presenting biocontrol potential against D. gallinae.


Assuntos
Aspergillus oryzae/fisiologia , Infestações por Ácaros/microbiologia , Controle Biológico de Vetores , Doenças das Aves Domésticas/terapia , Trombiculidae/microbiologia , Animais , Aspergillus oryzae/classificação , Aspergillus oryzae/genética , Aspergillus oryzae/patogenicidade , Estágios do Ciclo de Vida , Filogenia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/parasitologia
5.
Poult Sci ; 98(8): 3181-3193, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31220319

RESUMO

The objective of this study was to compare the effects of inorganic and proteinate Zn in chickens challenged with coccidia and Clostridium perfringens. A 3 × 2 factorial design was used, with 3 dietary formulations (0 or 90 mg/kg supplemental Zn from ZnSO4 or Zn proteinate, with or without challenge). On day 14, challenged birds were orally gavaged with approx. 5,000 Eimeria maxima sporulated oocysts, and on day 19 to 21 with C. perfringens (108 CFU/D). Productive performance was assessed at day 21 and 28. At 21 D, necrotic enteritis (NE) lesion severity, intestinal permeability, gene expression, and ileal and cecal microbiota were evaluated. An interaction of Zn source by challenge was observed for lesion score and mortality, wherein Zn supplementation decreased the degree of NE lesions (P = 0.02) and mortality due to NE (P = 0.008). In the jejunum, an interaction of Zn source by challenge was observed for the expression of IL-8 (P = 0.001) and INF-γ (P = 0.03), wherein the NE challenge upregulated their expression, but not in the Zn proteinate supplemented birds. Zn proteinate supplementation downregulated iNOS vs. ZnSO4 supplemented birds (P = 0.0003), and supplemental Zn downregulated TLR-2 (P = 0.05) and ZnT5 (P = 0.04), regardless of the source. In the ileal microbiota, Zn proteinate supplementation decreased the frequency of Lactobacillus (P = 0.01), and the challenge increased Enterobacteriaceae (P = 0.01). Dietary Zn decreased NE lesion severity and mortality due to NE; Zn proteinate led to lower expression of IL-8 and INF-γ in challenged birds which may be an indicative of a lessened inflammatory response.


Assuntos
Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Doenças das Aves Domésticas/imunologia , Sulfato de Zinco/farmacologia , Zinco/farmacologia , Ração Animal/análise , Animais , Galinhas , Infecções por Clostridium/veterinária , Clostridium perfringens/fisiologia , Coccidiose/veterinária , Dieta/veterinária , Eimeria/fisiologia , Enterite/veterinária , Intestinos/imunologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/parasitologia , Zinco/administração & dosagem
6.
BMC Vet Res ; 15(1): 212, 2019 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-31234834

RESUMO

BACKGROUND: Multi-drug resistant bacteria are seen increasingly and there are gaps in our understanding of the complexity of antimicrobial resistance, partially due to a lack of appropriate statistical tools. This hampers efficient treatment, precludes determining appropriate intervention points and renders prevention very difficult. METHODS: We re-analysed data from a previous study using additive Bayesian networks. The data contained information on resistances against seven antimicrobials and seven potential risk factors from 86 non-typhoidal Salmonella isolates from laying hens in 46 farms in Uganda. RESULTS: The final graph contained 22 links between risk factors and antimicrobial resistances. Solely ampicillin resistance was linked to the vaccinating person and disposal of dead birds. Systematic associations between ampicillin and sulfamethoxazole/trimethoprim and chloramphenicol, which was also linked to sulfamethoxazole/trimethoprim were detected. Sulfamethoxazole/trimethoprim was also directly linked to ciprofloxacin and trimethoprim. Trimethoprim was linked to sulfonamide and ciprofloxacin, which was also linked to sulfonamide. Tetracycline was solely linked to ciprofloxacin. CONCLUSIONS: Although the results needs to be interpreted with caution due to a small data set, additive Bayesian network analysis allowed a description of a number of associations between the risk factors and antimicrobial resistances investigated.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella/efeitos dos fármacos , Animais , Teorema de Bayes , Feminino , Fatores de Risco , Salmonella/classificação , Salmonella/isolamento & purificação , Uganda
7.
Vet Microbiol ; 234: 61-71, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31213273

RESUMO

Anti-phage activity of serum is of importance in repeated phage therapy. Higher serum anti-phage activity has been associated with greater susceptibility of phages to neutralisation and phage therapy failure. In this study, in vivo and in vitro survivability and immunogenicity of four coliphages (TM1, TM2, TM3 and TM4) were investigated in naive chickens and chickens pre-immunised with phage TM1. Furthermore, two phages that displayed different survivability and immunogenicity (TM1 and TM3) were compared with respect to their efficacy in treating naive or pre-immunised (TM1) chickens suffering from colibacillosis. The efficacy of the treatments was evaluated based on body weight, relative organ weights, mortality, E. coli counts in the lungs as well as severity and frequency of internal organ lesions. At the end of the experiment, both naive and pre-immunised chickens treated with TM3 showed significantly lower mortality and higher body weights than untreated chickens and those treated with TM1. The same trend was observed in incidence and severity of organ lesions as well as relative spleen weight. However, naive chickens treated with TM1 also showed a shortened inflammation period as indicated by spleen weights. E. coli counts in the lungs of chicken treated with TM3 were lower than those of chickens treated with TM1 on days 3 and 10 post challenge. These data indicate that the outcome of phage therapy and the impact of serum anti-phage activity are highly phage-type dependent in broilers.


Assuntos
Anticorpos Antivirais/sangue , Colífagos/imunologia , Infecções por Escherichia coli/veterinária , Terapia por Fagos/efeitos adversos , Doenças das Aves Domésticas/terapia , Animais , Galinhas , Escherichia coli , Infecções por Escherichia coli/terapia , Imunidade Humoral , Imunização , Imunoglobulina M/sangue , Imunoglobulinas/sangue , Inflamação , Pulmão/microbiologia , Pulmão/patologia , Terapia por Fagos/métodos , Doenças das Aves Domésticas/microbiologia , Soro , Baço/microbiologia , Baço/patologia
8.
Onderstepoort J Vet Res ; 86(1): e1-e8, 2019 May 30.
Artigo em Inglês | MEDLINE | ID: mdl-31170784

RESUMO

Salmonellosis is a major threat facing the poultry industry globally. This study was conducted to investigate the level of Salmonella contaminations and determine the resistance pattern of isolates obtained from selected poultry farms in Kwara State, a transition state between southern and northern regions of Nigeria. A total of 900 samples were collected between January and August 2017, from the poultry environment, apparently including healthy and dead birds. Salmonella was isolated and identified using standard bacteriological methods. All presumptive Salmonella isolates were serotyped and tested for antimicrobial susceptibility using 11 different antimicrobials. A total of 58 (6.4%) Salmonella isolates were obtained, and the isolation rate was only statistically significant (p < 0.05) in live birds. The isolates comprised of 13 serovars. The three predominant serovars, Salmonella enterica ser. 6.7:d:- (29.0%), Salmonella Agama (28.0%) and Salmonella Typhimurium (16.0%), were isolated from all three sample types. Rare serovars like Salmonella Albany, Salmonella Colindale, Salmonella Istanbul, Salmonella Larochelle, Salmonella Nigeria and Salmonella Orion were also isolated in this study. A high frequency of resistance was generally observed with all the isolates exhibiting a total of (100%) resistance to ampicillin, cefotaxime and ceftazidime. This study documents the first predominant isolation of S. enterica ser. 6.7:d:- and S. Agama from chickens. It also documents the high frequency of fluoroquinolone and cephalosporins resistance of the isolates indicating the presence of selective pressure in the environment. Controls and targeted interventions against Salmonella and the frequent occurrence of antimicrobial resistance in chickens should be initiated to prevent the spread of this organism.


Assuntos
Criação de Animais Domésticos , Antibacterianos/farmacologia , Galinhas , Doenças das Aves Domésticas/epidemiologia , Salmonelose Animal/epidemiologia , Salmonella enterica/isolamento & purificação , Animais , Antibacterianos/uso terapêutico , Fazendas , Testes de Sensibilidade Microbiana/veterinária , Nigéria/epidemiologia , Doenças das Aves Domésticas/sangue , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/microbiologia , Prevalência , Salmonelose Animal/tratamento farmacológico , Salmonelose Animal/microbiologia , Salmonella enterica/classificação , Salmonella enterica/efeitos dos fármacos , Sorogrupo
9.
Comp Immunol Microbiol Infect Dis ; 64: 163-167, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31174693

RESUMO

In the last few years, antimicrobial resistant (AMR) Escherichia coli have been detected in newborn chickens suggesting their vertical transmission from breeding birds to their offspring. However, little is known about the presence of AMR E. coli in the reproductive organs of broiler breeders. The aim of this study was to investigate the presence of E. coli in the ovaries of healthy broiler breeders and to study their antimicrobial resistance. Samples from broiler breeders (n = 80) collected from 80 different broiler breeder flocks were included in this study. Antibiotic susceptibility testing was performed using disk diffusion method according to Clinical and Laboratory Standards Institute guidelines. Minimal inhibitory concentrations (MICs) of five antimicrobial agents were determined by Etest. PCR and sequencing were used to detect the blaESBL genes. E. coli were detected in the ovaries of thirty seven out of 80 (46.25%) sampled flocks. High levels of resistance to various first-line antimicrobial agents were recorded in E. coli isolates. This study showed that 89.18% of E. coli isolates were multidrug resistant (MDR). Furthermore, MDR extended-spectrum ß-lactamases (ESBL)-producing E. coli were detected in the ovaries of four different broiler breeder flocks. Molecular characterization revealed that three isolates harboured blaCTX-M-1 gene and one isolate expressed blaSHV-12 gene. In addition, one blaCTX-M-1 -producing E. coli co-harboured the blaTEM-1 gene. These findings would contribute to a better epidemiological understanding of MDR E. coli for improve existing preventive strategies in order to reduce the dissemination of antimicrobial resistance in the broiler production system.


Assuntos
Farmacorresistência Bacteriana Múltipla , Infecções por Escherichia coli/veterinária , Escherichia coli/isolamento & purificação , Ovário/microbiologia , Doenças das Aves Domésticas/microbiologia , Argélia , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Cefalosporinas/farmacologia , Galinhas/microbiologia , Escherichia coli/enzimologia , Feminino , Testes de Sensibilidade Microbiana , beta-Lactamases/genética
10.
J Med Microbiol ; 68(7): 1003-1011, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31172912

RESUMO

PURPOSE: The present study aimed to establish pretreatment protocols as well as real-time and droplet digital polymerase chain reaction (PCR) methodologies to detect and quantify Erysipelothrix rhusiopathiae (ER) DNA in blood samples from infected chickens, as tools for routine diagnostics and monitoring of experimental infections. Chicken blood is a problematic matrix for PCR analysis because nucleated erythrocytes contribute large amounts of host DNA that inhibit amplification. METHODOLOGY: Using artificially spiked samples of fresh chicken blood, as well as blood samples from three experimental infection studies, the performance of pretreatment protocols, including choice of blood stabilization agent, centrifugation speeds and Ficoll gradient separation, was evaluated. The results were compared with those from traditional culture-based protocols combined with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS).Results/Key findings. Simple preparations producing cell-free samples performed well on artificial spike-in samples, providing high sensitivity. However, performance was poor in clinical samples or artificial samples where the bacteria were incubated for 4 h or more in fresh blood prior to DNA extraction. In these samples, a Ficoll separation protocol that creates samples rich in lymphocytes, monocytes and thrombocytes prior to DNA extraction was far more effective. CONCLUSIONS: Our results indicate that ER bacteria undergo rapid phagocytosis in chicken blood and that analysis of a blood fraction enriched for phagocytic cells is necessary for reliable detection and quantification. The presented results explain the poor performance of PCR detection reported in previously published experimental ER infection studies, and the proposed solutions are likely to have broader implications for PCR-based veterinary diagnostics in non-mammalian host species such as poultry and fish.


Assuntos
Galinhas/microbiologia , DNA Bacteriano/genética , Infecções por Erysipelothrix/microbiologia , Erysipelothrix/genética , Reação em Cadeia da Polimerase/veterinária , Doenças das Aves Domésticas/microbiologia , Animais , Erysipelothrix/isolamento & purificação , Infecções por Erysipelothrix/diagnóstico , Eritrócitos/citologia , Eritrócitos/microbiologia , Reação em Cadeia da Polimerase/métodos
11.
Microb Pathog ; 132: 222-229, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31059755

RESUMO

The emerging incidence of antibiotic resistance trait among the bacteria populating poultry presents a devastating public health issue. On the other hand, at present, diabetes and obesity are the most serious public health issues and are increasing subsequently at alarming rate. In view of this, the present in vitro context was aimed to investigate the antibacterial activities of Momordica charantia (M. charantia) fruits extracts against poultry associated Bacillus spp. and to assess further its phytoconstituents, alpha-(α)-glucosidase activities, and anti-obesity properties. The anti-pathogenic attributes of M. charantia fruit extracts were carried out using disc diffusion assay and results showed the pronounced antibacterial trait of ethanolic extract with maximum zone of inhibition of 28.3 ±â€¯1.2 mm against Bacillus licheniformis. The qualitative phytochemical analyses of fruit extracts illustrated the presence of diverse phytoconstituents. The α-glucosidase inhibition assay for the extracts was performed according to the α-glucosidase activity kit. The results depicted the lowest α-glucosidase activity (57.13 ±â€¯2.3 to 18.14 ±â€¯1.3 U/L) in the presence of ethanolic extract at varied concentrations. The anti-obesity potentialities of fruit extracts were demonstrated in terms of porcine pancreatic lipase (PPL type II) activity using p-nitro-phenyl butyrate (p-NPB) as a substrate. The ethanolic extract of M. charantia fruits was observed to exhibit maximum inhibition of pancreatic lipase ranging from 20.12 ±â€¯2.3 to 68.34 ±â€¯1.3% in a dose dependent manner with an IC50 value of 607.6 ±â€¯1.3 µg/mL. FTIR and GC-MS results indicated the presence of distinct compounds in the ethanol extract and major bioactive constituents were found to be Dimethyl sulfone (35.24%), 9-octadecanamide (20.52%), Pentadecanoic acid (6.64%), Lanost-9 (11)-en-18-oic acid, 23-(acetylxyl)-3-(4-bromobenzoyl) oxyl-20-hydroxyl-gamma-lactone (2.6%), and 2,2-sulfonyldiethanol (2.46%). In conclusion, M. charantia fruits could be of great concern in pharmaceutical industries due to its adequate biological properties and may also help in the management of poultry associated bacterial pathogens.


Assuntos
Antibacterianos/farmacologia , Bactérias/efeitos dos fármacos , Frutas/química , Momordica charantia/química , Extratos Vegetais/farmacologia , Animais , Fármacos Antiobesidade/farmacologia , Bacillus/efeitos dos fármacos , Lipase/metabolismo , Testes de Sensibilidade Microbiana , Compostos Fitoquímicos/química , Compostos Fitoquímicos/farmacologia , Extratos Vegetais/química , Aves Domésticas , Doenças das Aves Domésticas/tratamento farmacológico , Doenças das Aves Domésticas/microbiologia , Suínos , alfa-Glucosidases/metabolismo
12.
Microb Pathog ; 132: 325-334, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31082529

RESUMO

Specific pathogen-free (SPF) experimental animals are recognized as standard laboratory animals in the fields of biomedical, animal husbandry and veterinary research and production. Intestinal flora plays a critical role in nutrient absorption, improving health and protecting the host from pathogens. We therefore explored the variation and maintenance of intestinal flora in SPF chicks in order to better understand the composition of intestinal microflorain SPF chickens, and provide reference for the study of intestinal flora of SPF experimental animals. Five chicks were randomly selected at each of 14, 28, and 42 days, and ceca were removed for DNA extraction. The Illumina Miseq platform was used for microbiome analysis of the V3-V4 region of the 16S rRNA gene. During the course of chick gut microbiome development, we observed major changes in diversity, especially between day 14 and day 28. Firmicutes, Proteobacteria, and Bacteroidetes were the main bacterial taxa, and Firmicutes increased significantly with age. The genus with the highest relative abundance was Lactobacillus, followed by Faecalibacterium. In addition, while abundance of Ruminococcaceae spp., Ruminococcus, and Blautia increased with age, Lactobacillus, Enterobacteriaceae spp., and Oscillospira decreased with age. Interestingly, the abundance of Faecalibacterium first increased and then decreased over time. The characteristics of SPF chicken gut flora at different ages establish a basis for the regulation of intestinal flora in the early stage of brooding, and also provide a theoretical foundation for controlling and preventing infections and poultry diseases in newborn chickens.


Assuntos
Galinhas/microbiologia , Microbioma Gastrointestinal , Interações entre Hospedeiro e Microrganismos/fisiologia , Organismos Livres de Patógenos Específicos , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/crescimento & desenvolvimento , DNA Bacteriano/genética , Microbioma Gastrointestinal/genética , Interações entre Hospedeiro e Microrganismos/genética , Intestinos/microbiologia , Doenças das Aves Domésticas/microbiologia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
13.
Mol Immunol ; 111: 182-197, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31078054

RESUMO

The type VI secretion system (T6SS) has recently emerged as a new pattern of protein secretions in Campylobacter jejuni (C. jejuni). Within the T6SS cluster, hemolysin co-regulated protein (hcp) is considered as a hallmark of functional T6SS and holds key role in bacterial virulence. As poultry is the primary reservoir of C. jejuni and the major sources for human infection, we evaluated the capacity of recombinant hcp (rhcp) immunization in blocking C. jejuni colonization in chickens with an aim to control bacterial transmission to humans via poultry food chain. Considering the mucosal route is the primary portal for C. jejuni entry and gut mucosa offers the apposite site for C. jejuni adherence, we investigated the immune-protective potential of intra-gastric administration of rhcp using chitosan-based nanoparticles. To achieve this goal, full length coding sequence of hcp gene from C. jejuni was cloned and expressed in E. coli. Purified rhcp was entrapped in chitosan-Sodium tripolyphosphate nanoparticles (CS-TPP NPs) and orally gavaged in chickens. Our results suggest that intra-gastric immunization of CS-TPP-rhcp induces consistent and steady increase in intestinal (sIgA) and systemic antibody (IgY) response against rhcp with significant reduction in cecal load of C. jejuni. The protection afforded by rhcp associated cellular responses with Th1 and Th17 profile in terms of increased expression of NFkB, IL-1ß, IL-8, IL-6, IFN-γ and IL-17 A genes. Though systemic immunization of rhcp with IFA resulting in a robust systemic (IgY) and local (sIgA) antibody response, mucosal administration of rhcp loaded CS-TPP NPs was found to be superior in terms of bacterial clearance. Altogether, present study suggests that chitosan based intra-gastric delivery of rhcp have several advantages over the injectable composition and could be a promising vaccine approach to effectively control C. jejuni colonization in chickens.


Assuntos
Formação de Anticorpos/imunologia , Campylobacter jejuni/imunologia , Galinhas/imunologia , Mucosa Gástrica/imunologia , Proteínas com Ferro-Enxofre/imunologia , Proteínas Recombinantes/imunologia , Sistemas de Secreção Tipo VI/imunologia , Animais , Proteínas de Bactérias/imunologia , Vacinas Bacterianas/imunologia , Ceco/imunologia , Ceco/microbiologia , Galinhas/microbiologia , Escherichia coli/imunologia , Mucosa Gástrica/microbiologia , Proteínas Hemolisinas/imunologia , Imunização/métodos , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/microbiologia , Células Th1/imunologia , Células Th17/imunologia
14.
Br Poult Sci ; 60(4): 388-394, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31066296

RESUMO

1. Salmonella is one of the most important pathogens in public health and it is usually associated with food-borne diseases. Salmonella serovars Enteritidis and Typhimurium are widespread in the world with outbreaks frequently associated with consumption of poultry products; furthermore, there is an increasing public health concern with the wide dissemination of the serovar Heidelberg in poultry flocks. 2. The aim of the experiment was to develop and to validate rapid methods to detect Salmonella serovars Enteritidis, Typhimurium, and Heidelberg by real-time PCRs and test isolates from pre-enriched poultry samples. 3. Three real-time PCRs were developed and used in combination to detect the serovars Enteritidis, Typhimurium and Heidelberg. These assays were validated by the analysis of 126 Salmonella isolates, eight other enteric bacterial species and 34 naturally contaminated poultry samples after pre-enrichment with buffered peptone water (BPW). 4. Real-time PCRs detected the isolates of the most important poultry serovars (Enteritidis, Typhimurium and Heidelberg) with 100% inclusivity and exclusivity in each assay. The PCR identified monophasic variants of the serovars Typhimurium and Heidelberg. All PCRs were validated in detecting these specific serovars directly from pre-enriched poultry samples. The whole analytical procedure was performed in less than 24 h in a veterinary diagnostic laboratory.


Assuntos
Técnicas Bacteriológicas/métodos , Galinhas , Doenças das Aves Domésticas/tratamento farmacológico , Reação em Cadeia da Polimerase em Tempo Real/métodos , Salmonelose Animal/tratamento farmacológico , Salmonella enterica/isolamento & purificação , Perus , Animais , Técnicas Bacteriológicas/instrumentação , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/microbiologia , Salmonella enteritidis/isolamento & purificação , Salmonella typhimurium/isolamento & purificação
15.
Trop Anim Health Prod ; 51(6): 1559-1569, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31076994

RESUMO

A total of 464 samples comprising of cloacal swabs from necrotic enteritis suspected live birds (191), intestinal scrapings from dead birds with symptoms of necrotic enteritis (91), and apparently healthy birds (182) were collected from selected districts of AP. The samples were subjected to multiplex PCR for simultaneous detection of α, ß, and ß2 toxin genes and uniplex PCR for the detection of NetB gene. Multiplex PCR screening of samples reveled α toxin gene positives from (cpa) 248/282 (87.94%) necrotic enteritis suspected and 40/182 (21.97%) apparently healthy samples. Among cpa positives 142/248 (57.25%) and 3/40 (7.5%) were positive for ß2 toxin gene in necrotic enteritis suspected and apparently healthy birds respectively, indicating the involvement of C. perfringens type A, with minor pore forming toxin gene cpb2 in causing necrotic enteritis in poultry. None of the sample was positive for ß toxin gene. The present research indicates C. perfringens type A along with ß2 toxin gene was responsible for causing necrotic enteritis in broiler chickens in some parts of Andhra Pradesh in India. Phylogenetic relationship of amplified cpa and cpb2 amino acids sequences from present C. perfringens isolates were studied. The analysis reveals the sequence identity of cpb2 gene of the present isolates and variations at both nucleotide and amino acid level with the published sequences of cpb2 gene of C. perfringens isolates from different animal species of the USA, Iran, Netherlands, and Japan.


Assuntos
Galinhas , Infecções por Clostridium/veterinária , Clostridium perfringens/isolamento & purificação , Enterite/veterinária , Doenças das Aves Domésticas/microbiologia , Animais , Toxinas Bacterianas/genética , Infecções por Clostridium/microbiologia , DNA Bacteriano/química , Enterite/microbiologia , Reação em Cadeia da Polimerase Multiplex , Filogenia
16.
BMC Vet Res ; 15(1): 159, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31118039

RESUMO

BACKGROUND: Avian pathogenic Escherichia coli (APEC) is the principle cause of colibacillosis affecting poultry. The main challenge to the poultry industry is antimicrobial resistance and the emergence of multidrug resistant bacteria that threaten the safety of the food chain. Risk factors associated with emergence of antimicrobial resistance among avian pathogenic E. coli were correlated with the inappropriate use of antimicrobials along with inadequate hygienic practices, which encourages the selection pressure of antimicrobial resistant APEC. The aim of this study was to isolate, identify, serogroup and genotype APEC from broilers, assess their antibiotic resistance profile, expressed genes and the associated risk factors. RESULTS: APEC was isolated from the visceral organs of sick chickens with a prevalence of 53.4%. The most prevalent serotypes were O1, O2, O25 and O78, in percentage of 14.8, 12.6, 4.4 and 23.7%, respectively. Virulence Associated Genes; SitA, iss, iucD, iucC, astA, tsh cvi and irp2 were detected in rate of 97.4, 93.3, 75, 74, 71, 46.5, 39 and 34%, respectively and 186 (69.2%) isolates possess > 5-10 genes. The highest resistance was found against sulphamethoxazole-trimethoprim, florfenicol, amoxicillin, doxycycline and spectinomycin in percentage; 95.5, 93.7, 93.3, 92.2 and 92.2%, respectively. Sixty-eight percent of APEC isolates were found to have at least 5 out of 8 antimicrobial resistant genes. The most predominant genes were Int1 97%, tetA 78.4%, bla TEM 72.9%, Sul1 72.4%, Sul2 70.2%. Two risk factors were found to be associated with the presence of multi-drug resistant APEC in broiler chickens, with a P value ≤0.05; the use of ground water as source of drinking water and farms located in proximity to other farms. CONCLUSIONS: This study characterized the VAGs of avian pathogenic E. coli and establish their antimicrobial resistance patterns. The widespread of antimicrobial resistance of APEC isolates and detection of ARGs highlighted the need to monitor the spread of ARGs in poultry farms and the environment in Jordan. Use of ground water and closely located farms were significant risk factors associated with the presence of MDR APEC in broiler chickens in Jordan.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções por Escherichia coli/veterinária , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Doenças das Aves Domésticas/microbiologia , Criação de Animais Domésticos , Animais , Galinhas , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Água Subterrânea/microbiologia , Jordânia/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Fatores de Risco
17.
J Appl Microbiol ; 127(2): 396-405, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31075179

RESUMO

AIMS: This study was designed to investigate, in an in vivo setting, the effects of single and combined infections with either Mycoplasma gallisepticum (MG) and/or Escherichia coli on the chicken immune response induced by Newcastle disease virus (NDV) vaccine. METHODS AND RESULTS: Humoral immunity was measured through detection of NDV antibody and anti-NDV IgG titres using haemagglutination-inhibition test and enzyme-linked immunosorbent assay, respectively. In addition, the expression levels of pro-inflammatory cytokines' genes (interleukin (IL) 6, IL4 and interferon (IFN) γ) were analysed using quantitative reverse transcription PCR. Significant (P < 0·05) results in all immunological parameters were detected in the vaccinated noninfected chicken group in comparison with those in groups exposed to bacterial infections. Bacterial infection along with vaccination hampered the NDV antibodies production and reduced the vaccine upregulated cytokine genes. The vaccinated mixed infection group reported lower antibody titres and cytokines expression levels compared to those in the single infection groups. All the previously enhanced immunological parameters reflected the maximum protection post challenge with velogenic viscerotropic NDV in the vaccinated noninfected chicken group. CONCLUSIONS: These findings provide novel insights into the immunosuppression activities of MG and E. coli infection in chickens vaccinated against NDV. SIGNIFICANCE AND IMPACT OF THE STUDY: This study hopes to provide a better insight to the immunosuppressive action of bacterial pathogens in chickens. This will help to improve biosecurity strategies during NDV vaccination in the future.


Assuntos
Galinhas/imunologia , Infecções por Escherichia coli/veterinária , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/imunologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/biossíntese , Coinfecção/veterinária , Citocinas/genética , Citocinas/metabolismo , Infecções por Escherichia coli/imunologia , Imunidade Humoral , Infecções por Mycoplasma/imunologia , Doenças das Aves Domésticas/microbiologia
18.
Lett Appl Microbiol ; 69(2): 110-115, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31087370

RESUMO

This study was undertaken to detect the occurrence of beta-lactamase and biofilm producing Enterobacteriaceae in healthy ducks. A total 202 cloacal swabs were collected from ducks kept in organized (n = 92) and backyard (n = 110) farms in West Bengal (India). The ducks had no history of antibiotic intake. Among the 87 phenotypically beta-lactamase producing Escherichia coli, 19 (17·43%), 6 (5·05%) and 15 (13·76%) isolates possessed blaTEM , blaSHV and blaCTX-M respectively. Whereas, 5 (38·46%) Salmonella isolates were found to harbour blaCTX-M . In K. pneumoniae 10 (33·33%), 3 (13·33%), 4 (13·33%) isolates possessed blaTEM , blaSHV and blaCTX-M respectively. The sequences of selected PCR products were found 98% cognate with blaCTX-M-9, blaSHV-12 and blaTEM-1 . Beta-lactamase producing E. coli isolates belonged to 14 different serogroups such as O1, O2, O3, O5, O7, O8, O35, O83, O84, O88, O119, O128, O145 and O157. Moreover, 87 E. coli (79·82%), six Samonella (46·15%) and 13 K. pneumoniae (43·33%) isolates were detected as AmpC producers possessing blaAmpC . Majority of E. coli (46·79%), Salmonella (46·15%) and K. pneumoniae (70%) isolates were detected as biofilm producers and possessed the associated genes (csgA, sdiA, rcsA, rpoS). Significantly higher occurrence of beta-lactamase and biofilm producing Enterobacteriaceae isolates was detected in backyard ducks than organized farms. SIGNIFICANCE AND IMPACT OF THE STUDY: Consumption of antibiotic through feed or during therapy is considered as potential reason for generation of antimicrobial resistant bacteria in birds. This study provides valuable evidence that exposure to contaminated environment may be an additional source for generation of antimicrobial resistant bacteria in backyard ducks. The backyard ducks are reared by marginal farmers in India who cannot offer antibiotics to them either through feed or during therapy due to high cost. The study also reveals a significant correlation between biofilm formation and possession of antimicrobial resistance genes in the bacterial isolates from the ducks.


Assuntos
Biofilmes/crescimento & desenvolvimento , Patos/microbiologia , Infecções por Enterobacteriaceae/veterinária , Enterobacteriaceae/fisiologia , Doenças das Aves Domésticas/microbiologia , beta-Lactamases/genética , Animais , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Fazendas , Feminino , Índia/epidemiologia , Masculino , Fenótipo , Doenças das Aves Domésticas/epidemiologia
19.
Prev Vet Med ; 168: 39-51, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-31097122

RESUMO

A national baseline study was conducted between December 2012 and December 2013 to determine the pre-packaging prevalence and concentration of foodborne pathogens on broiler chicken carcasses and parts at processing; a survey was implemented simultaneously to collect data on the processing practices used to control these pathogens. Thirty federally-registered Canadian poultry processing establishments completed the questionnaire. A total of 2,732 samples of carcasses and parts (breast and thigh pieces) were collected over the study period from these establishments. For Salmonella, the overall proportion positive was 0.22 (95% CI 0.20, 0.23), and the mean concentration was 0.67 (95% CI 0.51, 0.83) MPN/mL of rinse fluid. Multivariable regression models with random intercepts for the establishment and the date of sampling were used to identify associations between Salmonella prevalence and concentration and processing practices. In the final logistic regression model for the prevalence outcome (positive or negative sample), there were three statistically significant variables: product type (carcass or part); chilling method (water or air); and chlorine use in the establishment (chlorine, cetylpyridinium chloride, or neither). The likelihood of testing positive for Salmonella was higher on parts than carcasses (OR 3.03, 95% CI 2.38, 3.86), and higher when cetylpyridinium chloride was used (OR 2.00, 95% CI 1.36, 2.95), or when other processing aids were used (OR 1.99, 95% CI 1.26, 3.15), than when chlorine was used. Water chilling was negatively associated with testing positive for Salmonella when compared with air chilling (OR 0.68, 95% CI 0.48, 0.96). In the final linear regression model for the concentration outcome (log10 MPN/mL), there was one statistically significant variable chilling method, where water chilling was associated with a decrease in concentration (ß -0.23, 95% CI -0.38, -0.08 log10 MPN/mL). The intraclass correlation coefficients for establishment and date sampling were 0.02 and 0.23 in the linear regression model, and 0.01 and 0.34 in the logistic regression model, respectively. Further studies to explore the methods to reduce microbial contamination during the air chilling and cut-up and boning processes in broiler chicken establishments in Canada are recommended.


Assuntos
Galinhas , Manipulação de Alimentos , Doenças das Aves Domésticas/epidemiologia , Produtos Avícolas/microbiologia , Salmonelose Animal/epidemiologia , Matadouros , Animais , Canadá/epidemiologia , Indústria de Embalagem de Carne , Doenças das Aves Domésticas/microbiologia , Prevalência , Salmonella , Salmonelose Animal/etiologia
20.
Vet Res ; 50(1): 38, 2019 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-31118094

RESUMO

Footpad lesions are an important factor in evaluation of animal welfare in broilers regulated by law; however, no legal requirements have been set for the parent birds. Nevertheless, the present study confirms that foot health in broiler breeders declines significantly with increasing age, thus potentially impairing the animal welfare due to pain and discomfort from footpad dermatitis. Furthermore, this is the first report demonstrating a correlation between the presence of footpad lesions and systemic bacterial infections with Gram-positive cocci in broiler breeder birds.


Assuntos
Infecções Bacterianas/veterinária , Pé/patologia , Doenças das Aves Domésticas/microbiologia , Fatores Etários , Animais , Infecções Bacterianas/microbiologia , Infecções Bacterianas/patologia , Galinhas/microbiologia , Pé/microbiologia , Doenças das Aves Domésticas/patologia
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