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1.
Molecules ; 26(5)2021 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-33652818

RESUMO

Glaesserella parasuis (G. parasuis) causes inflammation and damage to piglets. Whether polyserositis caused by G. parasuis is due to tight junctions damage and the protective effect of baicalin on it have not been examined. Therefore, this study aims to investigate the effects of baicalin on peritoneal tight junctions of piglets challenged with G. parasuis and its underlying molecular mechanisms. Piglets were challenged with G. parasuis and treated with or without baicalin. RT-PCR was performed to examine the expression of peritoneal tight junctions genes. Immunofluorescence was carried out to detect the distribution patterns of tight junctions proteins. Western blot assays were carried out to determine the involved signaling pathways. Our data showed that G. parasuis infection can down-regulate the tight junctions expression and disrupt the distribution of tight junctions proteins. Baicalin can alleviate the down-regulation of tight junctions mRNA in peritoneum, prevent the abnormalities and maintain the continuous organization of tight junctions. Our results provide novel evidence to support that baicalin has the capacity to protect peritoneal tight junctions from G. parasuis-induced inflammation. The protective mechanisms of baicalin could be associated with inhibition of the activation of PKC and MLCK/MLC signaling pathway. Taken together, these data demonstrated that baicalin is a promising natural agent for the prevention and treatment of G. parasuis infection.


Assuntos
Flavonoides/farmacologia , Infecções por Pasteurellaceae/tratamento farmacológico , Pasteurellaceae/efeitos dos fármacos , Doenças dos Suínos/tratamento farmacológico , Animais , Pasteurellaceae/genética , Pasteurellaceae/patogenicidade , Infecções por Pasteurellaceae/genética , Infecções por Pasteurellaceae/microbiologia , Infecções por Pasteurellaceae/veterinária , Peritônio/efeitos dos fármacos , Peritônio/microbiologia , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , Suínos , Doenças dos Suínos/microbiologia , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/genética , Junções Íntimas/microbiologia
2.
Methods Mol Biol ; 2291: 19-86, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33704748

RESUMO

Cattle and other ruminants are primary reservoirs for Shiga toxin-producing Escherichia coli (STEC) strains which have a highly variable, but unpredictable, pathogenic potential for humans. Domestic swine can carry and shed STEC, but only STEC strains producing the Shiga toxin (Stx) 2e variant and causing edema disease in piglets are considered pathogens of veterinary medical interest. In this chapter, we present general diagnostic workflows for sampling livestock animals to assess STEC prevalence, magnitude, and duration of host colonization. This is followed by detailed method protocols for STEC detection and typing at genetic and phenotypic levels to assess the relative virulence exerted by the strains.


Assuntos
Doenças dos Bovinos , Infecções por Escherichia coli , Toxina Shiga II/metabolismo , Escherichia coli Shiga Toxigênica , Doenças dos Suínos , Animais , Bovinos , Doenças dos Bovinos/diagnóstico , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/microbiologia , Infecções por Escherichia coli/diagnóstico , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli Shiga Toxigênica/classificação , Escherichia coli Shiga Toxigênica/isolamento & purificação , Escherichia coli Shiga Toxigênica/metabolismo , Escherichia coli Shiga Toxigênica/patogenicidade , Suínos , Doenças dos Suínos/diagnóstico , Doenças dos Suínos/metabolismo , Doenças dos Suínos/microbiologia
3.
J Anim Sci ; 99(2)2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33529342

RESUMO

High dietary protein may increase susceptibility of weaned pigs to enteric pathogens. Dietary supplementation with functional amino acids (FAA) may improve growth performance of pigs during disease challenge. The objective of this study was to evaluate the interactive effects of dietary protein content and FAA supplementation above requirements for growth on performance and immune response of weaned pigs challenged with Salmonella. Sixty-four mixed-sex weanling pigs (13.9 ± 0.82 kg) were randomly assigned to dietary treatments in a 2 × 2 factorial arrangement with low (LP) or high protein (HP) content and basal (AA-) or FAA profile (AA+; Thr, Met, and Trp at 120% of requirements) as factors. After a 7-d adaptation period, pigs were inoculated with either a sterile saline solution (CT) or saline solution containing Salmonella Typhimurium (ST; 3.3 × 109 CFU/mL). Growth performance, body temperature, fecal score, acute-phase proteins, oxidant/antioxidant balance, ST shedding score in feces and intestinal colonization, fecal and digesta myeloperoxidase (MPO), and plasma urea nitrogen (PUN) were measured pre- and postinoculation. There were no dietary effects on any measures pre-inoculation or post-CT inoculation (P > 0.05). Inoculation with ST increased body temperature and fecal score (P < 0.05), serum haptoglobin, plasma superoxide dismutase (SOD), malondialdehyde (MDA), PUN, and fecal MPO, and decreased serum albumin and plasma reduced glutathione (GSH):oxidized glutathione (GSSG) compared with CT pigs (P < 0.05). ST-inoculation reduced average daily gain (ADG) and feed intake (ADFI) vs. CT pigs (P < 0.05) but was increased by AA+ vs. AA- in ST pigs (P < 0.05). Serum albumin and GSH:GSSG were increased while haptoglobin and SOD were decreased in ST-inoculated pigs fed AA+ vs. AA- (P < 0.05). PUN was higher in HP vs. LP-fed pigs postinoculation (P < 0.05). Fecal ST score was increased in ST-inoculated pigs on days 1 and 2 postinoculation and declined by day 6 (P < 0.05) in all pigs while the overall score was reduced in AA+ vs. AA- pigs (P < 0.05). Cecal digesta ST score was higher in HP vs. LP-fed pigs and were lower in AA+ compared with AA- fed pigs in the colon (P < 0.05). Fecal and digesta MPO were reduced in ST pigs fed AA+ vs. AA- (P < 0.05). These results demonstrate a positive effect of FAA supplementation, with minimal effects of dietary protein, on performance and immune status in weaned pigs challenged with Salmonella.


Assuntos
Aminoácidos/administração & dosagem , Ração Animal/análise , Fenômenos Fisiológicos da Nutrição Animal , Salmonella typhimurium , Doenças dos Suínos , Suínos/crescimento & desenvolvimento , Animais , Dieta/veterinária , Proteínas na Dieta/administração & dosagem , Suplementos Nutricionais , Doenças dos Suínos/microbiologia , Doenças dos Suínos/prevenção & controle , Desmame
4.
Vet Res ; 52(1): 30, 2021 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-33618766

RESUMO

Host proteins interacting with pathogens are receiving more attention as potential therapeutic targets in molecular medicine. Streptococcus suis serotype 2 (SS2) is an important cause of meningitis in both humans and pigs worldwide. SS2 Enolase (Eno) has previously been identified as a virulence factor with a role in altering blood brain barrier (BBB) integrity, but the host cell membrane receptor of Eno and The mechanism(s) involved are unclear. This study identified that SS2 Eno binds to 40S ribosomal protein SA (RPSA) on the surface of porcine brain microvascular endothelial cells leading to activation of intracellular p38/ERK-eIF4E signalling, which promotes intracellular expression of HSPD1 (heat-shock protein family D member 1), and initiation of host-cell apoptosis, and increased BBB permeability facilitating bacterial invasion. This study reveals novel functions for the host-interactional molecules RPSA and HSPD1 in BBB integrity, and provides insight for new therapeutic strategies in meningitis.


Assuntos
Barreira Hematoencefálica , Células Endoteliais/metabolismo , Fosfopiruvato Hidratase/metabolismo , Proteínas Ribossômicas/metabolismo , Infecções Estreptocócicas/veterinária , Streptococcus suis/metabolismo , Animais , Apoptose , Técnicas de Cocultura , Células Endoteliais/microbiologia , Fator de Iniciação 4E em Eucariotos/genética , Fator de Iniciação 4E em Eucariotos/metabolismo , MAP Quinases Reguladas por Sinal Extracelular/genética , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Regulação da Expressão Gênica , Proteínas de Choque Térmico/genética , Proteínas de Choque Térmico/metabolismo , Camundongos , Ligação Proteica , Sorogrupo , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/patologia , Streptococcus suis/patogenicidade , Suínos , Doenças dos Suínos/microbiologia , Proteínas Quinases p38 Ativadas por Mitógeno/genética , Proteínas Quinases p38 Ativadas por Mitógeno/metabolismo
5.
Gene ; 773: 145415, 2021 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-33444678

RESUMO

Heat shock protein 27 (HSP27) plays an important role in protecting cells from various stress factors. This study aimed to investigate the function of HSP27 gene and its regulatory mechanism as infected by Escherichia coli (E. coli) at the tissue and cellular levels. Real-time PCR was used to detect the differential expression of HSP27 gene in F18 resistant and sensitive Sutai pigs and the differential expression upon E. coli F18ab, F18ac, K88ac bacterial supernatant, thallus infection and LPS induction in IPEC-J2. In addition, the HSP27 gene overexpression vector was constructed to detect the effect of the HSP27 gene overexpression on the adhesion of E. coli F18 to IPEC-J2, secretion of pro-inflammatory factors, and the expression of the upstream key genes in Mitogen-activated protein kinase (MAPK) pathway. Ribosomal S6 kinase (RSK2) is an important protein in the MAPK pathway. Therefore, the RSK2 gene overexpression vector was constructed and the number of colonies was counted after co-transfection of HSP27 and RSK2 gene. Results revealed that the expression level of HSP27 gene in resistant individuals in 11 tissues was higher than sensitive type. At the cellular level, the relative expression levels of HSP27 gene were increased after F18ab, F18ac bacterial supernatant, F18ab thallus infection, and LPS induction for 4 h (P < 0.01). The adhesion ability of E. coli F18ab to IPEC-J2 was significantly reduced after HSP27 gene overexpression (P < 0.01), and the concentration of pro-inflammatory factors in the HSP27 gene overexpression group was significantly reduced compared with the control group after F18ab infection (P < 0.05). Furthermore, the expression of RSK2 was significantly increased in HSP27 overexpression group upon F18ab infection (P < 0.01). The colonies quantitative results also showed that the number of colonies was significantly reduced after co-transfection of HSP27 and RSK2 gene. We indicated that the high expression of HSP27 gene may resist the inflammatory response caused by exogenous stress and enhance the ability of IPEC-J2 to resist E. coli F18 infection. RSK2 gene in the MAPK pathway may cooperate with HSP27 gene to participate in the immune response of the organism, which provides a theoretical basis for the study of the mechanism of anti-E. coli infection in piglets.


Assuntos
Resistência à Doença/genética , Infecções por Escherichia coli/genética , Escherichia coli/genética , Proteínas de Choque Térmico HSP27/genética , Animais , Aderência Bacteriana/genética , Diarreia/genética , Diarreia/microbiologia , Diarreia/veterinária , Escherichia coli/patogenicidade , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/patologia , Proteínas de Escherichia coli/genética , Regulação da Expressão Gênica/genética , Suínos/genética , Suínos/microbiologia , Doenças dos Suínos/genética , Doenças dos Suínos/microbiologia
6.
PLoS One ; 15(12): e0244227, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33347506

RESUMO

BACKGROUND: A zoonotic association has been suggested for several PCR ribotypes (RTs) of Clostridioides difficile. In central parts of Sweden, RT046 was found dominant in neonatal pigs at the same time as a RT046 hospital C. difficile infection (CDI) outbreak occurred in the southern parts of the country. OBJECTIVE: To detect possible transmission of RT046 between pig farms and human CDI cases in Sweden and investigate the diversity of RT046 in the pig population using whole genome sequencing (WGS). METHODS: WGS was performed on 47 C. difficile isolates from pigs (n = 22), the farm environment (n = 7) and human cases of CDI (n = 18). Two different core genome multilocus sequencing typing (cgMLST) schemes were used together with a single nucleotide polymorphisms (SNP) analysis and the results were related to time and location of isolation of the isolates. RESULTS: The pig isolates were closely related (≤6 cgMLST alleles differing in both cgMLST schemes) and conserved over time and were clearly separated from isolates from the human hospital outbreak (≥76 and ≥90 cgMLST alleles differing in the two cgMLST schemes). However, two human isolates were closely related to the pig isolates, suggesting possible transmission. The SNP analysis was not more discriminate than cgMLST. CONCLUSION: No general pattern suggesting zoonotic transmission was apparent between pigs and humans, although contrasting results from two isolates still make transmission possible. Our results support the need for high resolution WGS typing when investigating hospital and environmental transmission of C. difficile.


Assuntos
/transmissão , Infecções por Clostridium/transmissão , Genoma Bacteriano , Doenças dos Suínos/transmissão , Animais , /patogenicidade , Infecções por Clostridium/microbiologia , Infecções por Clostridium/veterinária , Humanos , Polimorfismo de Nucleotídeo Único , Suínos , Doenças dos Suínos/microbiologia
7.
PLoS One ; 15(10): e0238939, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33017441

RESUMO

Long-term use of colistin for preventing Gram-negative bacterial infections in food animals was prohibited in Thailand in 2017, but it is permitted for short-term treatment. This study aimed to investigate association between the use of colistin for short-term treatment of infection and the emergence of colistin-resistant Enterobacteriaceae in swine. The current study was conducted at 2 selected swine farms in Thailand. Neither farm has used colistin to prevent infection for longer than 1 year. Rectal swabs were collected from the same 66 pigs at birth, and on days 7, 14, 21, 28, and 60. Colistin was used to treat sick pigs for up to 3 days. Additional rectal swabs were collected during colistin treatment. Rectal swabs were analyzed for colistin-resistant Enterobacteriaceae and the mcr-1 gene. Results revealed that colistin-resistant Enterobacteriaceae were absent at birth. Some pigs at both farms had diarrhea and received colistin treatment during days 2-27. Colistin-resistant Enterobacteriaceae were detected in 13.3-50.0% of sick and healthy pigs. No sick pigs were observed during days 28-60, and colistin was not used during that period. Colistin-resistant Enterobacteriaceae were detected in 2.8-10.0% of healthy pigs on day 28, and in 0-3.4% of healthy pigs on day 60. The mcr-1 gene was detected in 57.6% of colistin-resistant Enterobacteriaceae isolates. Short-term treatment with colistin was found to be associated with the emergence of colistin-resistant Enterobacteriaceae in swine. Colistin-resistant Enterobacteriaceae rapidly emerged after colistin use, and rapidly decreased or disappeared after its discontinuation.


Assuntos
Antibacterianos/uso terapêutico , Colistina/uso terapêutico , Infecções por Bactérias Gram-Negativas/veterinária , Sus scrofa/microbiologia , Doenças dos Suínos/tratamento farmacológico , Doenças dos Suínos/microbiologia , Animais , Animais Recém-Nascidos , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Fazendas , Feminino , Genes Bacterianos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Masculino , Gravidez , Suínos , Tailândia
8.
Anim Sci J ; 91(1): e13475, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33078490

RESUMO

Growth performance of pigs has been associated with healthy gut microbiota. To improve production, pigs are usually treated with antimicrobials. Nonetheless, while antimicrobials harm the gut-indigenous microbiota, probiotic supplementation seems to help keep it healthy. Here, using antimicrobials, we artificially induced dysbiosis in pigs and evaluated a possible preventive effect of probiotic supplementation. Three 6-week-old piglets were given a basal feed, and 3 more the feed supplemented with 2.0 × 106  CFU of Bacillus subtilis QST713/g of feed. After 14 days, antimicrobial enrofloxacin (5 mg/kg B.W.) was injected intramuscularly to all pigs on days 14-16. Feces were collected on days 14, 17, 19, 21, and 23. Total bacteria count was unaffected by enrofloxacin or QST713. However, Lactobacillus spp. and, in particular, Escherichia coli were affected by enrofloxacin, the latter not being observed in the feces on days 17 and 19. Interestingly, a reciprocal increase in E. coli was observed in control pigs on days 21 and 23, although in QST713-supplemented piglets, this increase was attenuated. While the gut microbiota composition did not return to initial levels in antimicrobial-administered piglets, it did in QST713-supplemented piglets. QST713 supplementation was likely crucial to keep the microbiota of piglets healthy.


Assuntos
Antibacterianos/efeitos adversos , Bacillus subtilis , Suplementos Nutricionais , Disbiose/prevenção & controle , Disbiose/veterinária , Enrofloxacina/efeitos adversos , Probióticos/administração & dosagem , Doenças dos Suínos/prevenção & controle , Animais , Antibacterianos/administração & dosagem , Disbiose/induzido quimicamente , Disbiose/microbiologia , Enrofloxacina/administração & dosagem , Fezes/microbiologia , Microbioma Gastrointestinal , Injeções Intramusculares , Suínos , Doenças dos Suínos/induzido quimicamente , Doenças dos Suínos/microbiologia
9.
Appl Environ Microbiol ; 86(23)2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-32948526

RESUMO

This study aimed to characterize in silico enterotoxigenic Escherichia coli F4- and F18-positive isolates (n = 90) causing swine postweaning diarrhea, including pathogenic potential, phylogenetic relationship, antimicrobial and biocide resistance, prophage content, and metal tolerance rates. F4 strains belonged mostly to the O149 and O6 serogroups and ST100 and ST48 sequence types (STs). F18 strains were mainly assigned to the O8 and O147 serogroups and ST10, ST23, and ST42. The highest rates of antimicrobial resistance were found against streptomycin, sulfamethoxazole, tetracycline, trimethoprim, and ampicillin. No resistance was found toward ciprofloxacin, cefotaxime, ceftiofur, and colistin. Genes conferring tolerance to copper (showing the highest diversity), cadmium, silver, and zinc were predicted in all genomes. Enterotoxin genes (ltcA, 100% F4, 62% F18; astA, 100% F4, 38.1% F18; sta, 18.8% F4, 38.1% F18; stb, 100% F4, 76.2% F18) and fimbria-encoding genes typed as F4ac and F18ac were detected in all strains, in addition to up to 16 other virulence genes in individual strains. Phage analysis predicted between 7 and 20 different prophage regions in each strain. A highly diverse variety of plasmids was found; IncFII, IncFIB, and IncFIC were prevalent among F4 isolates, while IncI1 and IncX1 were dominant among F18 strains. Interestingly, F4 isolates from the early 1990s belonged to the same clonal group detected for most of the F4 strains from 2018 to 2019 (ONT:H10-A-ST100-CH27-0). The small number of single-nucleotide polymorphism differences between the oldest and recent F4 ST100 isolates suggests a relatively stable genome. Overall, the isolates analyzed in this study showed remarkably different genetic traits depending on the fimbria type.IMPORTANCE Diarrhea in the postweaning period due to enterotoxigenic E. coli (ETEC) is an economically relevant disease in pig production worldwide. In Denmark, prevention is mainly achieved by zinc oxide administration (to be discontinued by 2022). In addition, a breeding program has been implemented that aims to reduce the prevalence of this illness. Treatment with antimicrobials contributes to the problem of antimicrobial resistance (AMR) development. As a novelty, this study aims to deeply understand the genetic population structure and variation among diarrhea-associated isolates by whole-genome sequencing characterization. ST100-F4ac is the dominant clonal group circulating in Danish herds and showed high similarity to ETEC ST100 isolates from China, the United States, and Spain. High rates of AMR and high diversity of virulence genes were detected. The characterization of diarrhea-related ETEC is important for understanding the disease epidemiology and pathogenesis and for implementation of new strategies aiming to reduce the impact of the disease in pig production.


Assuntos
Diarreia/veterinária , Escherichia coli Enterotoxigênica/genética , Infecções por Escherichia coli/veterinária , Genoma Bacteriano , Doenças dos Suínos/epidemiologia , Animais , Dinamarca/epidemiologia , Diarreia/epidemiologia , Diarreia/microbiologia , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Filogenia , Suínos , Doenças dos Suínos/microbiologia
10.
J Anim Sci ; 98(9)2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32877510

RESUMO

The study was conducted to investigate the efficacy of a probiotic Bacillus subtilis strain on growth performance, diarrhea, systemic immunity, and intestinal health of weaned pigs experimentally infected with an enterotoxigenic Escherichia coli and to compare the efficacy of B. subtilis with that of carbadox. Weaned pigs (n = 48, 6.17 ± 0.36 kg body weight [BW]) were individually housed in disease containment rooms and randomly allotted to one of four dietary treatments: negative control (NC, control diet without E. coli challenge), positive control (PC, control diet with E. coli challenge), and supplementation of 50 mg/kg of carbadox (antibiotic growth promotor [AGP]) or 2.56 × 109 CFU/kg of B. subtilis probiotics (PRO). The experiment lasted for 28 d with 7 d before and 21 d after the first E. coli inoculation. Fecal and blood samples were collected on days 0, 3, 7, 14, and 21 post inoculation (PI) to analyze ß-hemolytic coliforms and complete blood cell count, respectively. Diarrhea score was recorded daily for each pig to calculate the frequency of diarrhea. All pigs were euthanized at day 21 PI to collect jejunal and ileal mucosa for gene expression analysis. Pigs in AGP had greater (P < 0.05) BW on days 7, 14, and 21 PI than pigs in PC and PRO groups. Supplementation of PRO enhanced pigs' BW on day 21 PI compared with the PC. Escherichia coli F18 challenge reduced (P < 0.05) average daily gain (ADG) and feed efficiency from day 0 to 21 PI, while supplementation of carbadox or PRO enhanced ADG and feed efficiency in E. coli F18-challenged pigs from day 0 to 21 PI. Pigs in AGP and PRO groups had reduced (P < 0.05) frequency of diarrhea throughout the experiment and fecal ß-hemolytic coliforms on day 7 PI than pigs in the PC. Pigs in PRO had greater (P < 0.05) gene expression of CLDN1 in jejunal mucosa than pigs in the PC. Supplementation of carbadox or PRO reduced (P < 0.05) the gene expression of IL6 and PTGS2 in ileal mucosa of E. coli-infected pigs compared with pigs in the PC. Pigs in the PRO group had lower (P < 0.05) white blood cell number and neutrophil count, and serum haptoglobin concentration on day 7 PI, and less (P < 0.05) monocyte count on day 14 PI, compared with PC. In conclusion, supplementation of probiotic B. subtilis could enhance disease resistance and promote the growth performance of weaned pigs under disease challenge conditions. The potential mechanisms include but not limited to enhanced gut barrier integrity and local and systemic immune responses of weaned pigs.


Assuntos
Antibacterianos/farmacologia , Bacillus subtilis/fisiologia , Carbadox/farmacologia , Diarreia/veterinária , Infecções por Escherichia coli/veterinária , Probióticos/farmacologia , Doenças dos Suínos/microbiologia , Animais , Diarreia/tratamento farmacológico , Diarreia/microbiologia , Dieta/veterinária , Escherichia coli Enterotoxigênica/fisiologia , Infecções por Escherichia coli/tratamento farmacológico , Infecções por Escherichia coli/microbiologia , Fezes/microbiologia , Feminino , Íleo/efeitos dos fármacos , Íleo/microbiologia , Mucosa Intestinal/efeitos dos fármacos , Mucosa Intestinal/microbiologia , Masculino , Distribuição Aleatória , Suínos , Doenças dos Suínos/tratamento farmacológico , Desmame
11.
PLoS One ; 15(7): e0236887, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32735621

RESUMO

Lawsonia intracellularis, an obligately intracellular enteric bacterium, infects intestinal epithelial cells, but may also be found within macrophages in the intestinal lamina propria of affected pigs. Macrophages play an important role in host defense against infectious agents, but the role of this cell in L. intracellularis infection is not well understood. The aim of this study was to evaluate the permissibility of macrophages to L. intracellularis infection in vitro. Pure culture of L. intracellularis was added to swine peripheral blood monocyte-derived macrophages. Viability of intracytoplasmic L. intracellularis was evaluated at different time points by transmission electron microscopy (TEM). Potential replication of L. intracellularis in macrophages was also evaluated by qPCR. By TEM, phagocytosis L. intracellularis within of phagolysosomes were observed 1-hour post-infection (hpi) and bacterial structures in binary fission at 48 hpi. The number of intracellular bacteria was determined at 1, 4, 24, 48, and 72 hpi by qPCR in infected macrophages and compared to the number of intracellular bacteria from culture in McCoy cells. In both cell lines, the amount of L. intracellularis was decreased at 4 hpiand increased at 24 hpi. The number of intracellular bacteria continued to increase in McCoy cells over time. This is the first study showing interaction, survival and propagation of L. intracellularis in macrophages. These findings are critical to establish an experimental model for future studies of the pathogenesis of porcine proliferative enteropathy and the potential persistence of L. intracellularis in macrophages during chronic infections.


Assuntos
Infecções por Desulfovibrionaceae/veterinária , Lawsonia (Bactéria) , Macrófagos/microbiologia , Animais , Linhagem Celular , Enteropatias/microbiologia , Enteropatias/veterinária , Lawsonia (Bactéria)/crescimento & desenvolvimento , Lawsonia (Bactéria)/ultraestrutura , Fagocitose , Suínos , Doenças dos Suínos/microbiologia
12.
J Anim Sci ; 98(9)2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32780110

RESUMO

The objective was to study the effects of microencapsulated organic acids (OA) and essential oils (EO) on growth performance, immune system, gut barrier function, nutrient digestion and absorption, and abundance of enterotoxigenic Escherichia coli F4 (ETEC F4) in the weaned piglets challenged with ETEC F4. Twenty-four ETEC F4 susceptible weaned piglets were randomly distributed to 4 treatments including (1) sham-challenged control (SSC; piglets fed a control diet and challenged with phosphate-buffered saline (PBS)); (2) challenged control (CC; piglets fed a control diet and challenged with ETEC F4); (3) antibiotic growth promoters (AGP; CC + 55 mg·kg-1 of Aureomycin); and (4) microencapsulated OA and EO [P(OA+EO); (CC + 2 g·kg-1 of microencapsulated OA and EO]. The ETEC F4 infection significantly induced diarrhea at 8, 28, 34, and 40 hr postinoculation (hpi) (P < 0.05) in the CC piglets. At 28 d postinoculation (dpi), piglets fed P(OA+EO) had a lower (P < 0.05) diarrhea score compared with those fed CC, but the P(OA+EO) piglets had a lower (P < 0.05) diarrhea score compared with those fed the AGP diets at 40 dpi. The ETEC F4 infection tended to increase in vivo gut permeability measured by the oral gavaging fluorescein isothiocyanate-dextran 70 kDa (FITC-D70) assay in the CC piglets compared with the SCC piglets (P = 0.09). The AGP piglets had higher FITC-D70 flux than P(OA+EO) piglets (P < 0.05). The ETEC F4 infection decreased mid-jejunal VH in the CC piglets compared with the SCC piglets (P < 0.05). The P(OA+EO) piglets had higher (P < 0.05) VH in the mid-jejunum than the CC piglets. The relative mRNA abundance of Na+-glucose cotransporter and B0AT1 was reduced (P < 0.05) by ETEC F4 inoculation when compared with the SCC piglets. The AGP piglets had a greater relative mRNA abundance of B0AT1 than the CC piglets (P < 0.05). The ETEC F4 inoculation increased the protein abundance of OCLN (P < 0.05), and the AGP piglets had the lowest relative protein abundance of OCLN among the challenged groups (P < 0.05). The supplementation of microencapsulated OA and EO enhanced intestinal morphology and showed anti-diarrhea effects in weaned piglets challenged with ETEC F4. Even if more future studies can be required for further validation, this study brings evidence that microencapsulated OA and EO combination can be useful within the tools to be implemented in strategies for alternatives to antibiotics in swine production.


Assuntos
Diarreia/veterinária , Escherichia coli Enterotoxigênica/crescimento & desenvolvimento , Infecções por Escherichia coli/veterinária , Microbioma Gastrointestinal/efeitos dos fármacos , Óleos Voláteis/farmacologia , Doenças dos Suínos/microbiologia , Animais , Antibacterianos/farmacologia , Ácidos Carboxílicos/farmacologia , Clortetraciclina/farmacologia , Diarreia/microbiologia , Dieta/veterinária , Composição de Medicamentos/veterinária , Escherichia coli Enterotoxigênica/efeitos dos fármacos , Infecções por Escherichia coli/microbiologia , Feminino , Imunidade , Jejuno/efeitos dos fármacos , Masculino , Nutrientes/metabolismo , Distribuição Aleatória , Suínos , Desmame
13.
Virology ; 548: 200-212, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32763491

RESUMO

The intestinal microbiota is crucial to intestinal homeostasis. Porcine epidemic diarrhea virus (PEDV) is high pathogenic to intestines, causing diarrhea, even death in piglets. To investigate the detailed relationship between PEDV infection and intestinal microbiota, the composition and distribution of intestinal microbiota from pigs were first analyzed using 16S rRNA sequencing technology. The results demonstrated that the composition and distribution of microbes in different intestinal segments were quite similar between 1-week-old and 2-week-old piglets but different from 4-week-old (weaned) piglets. Then piglets at different ages were inoculated with PEDV. The results showed that the 1-week-old piglets exhibited the most severe pathogenicity comparing to the other age groups. Further investigations indicated that Lactobacillus, Escherichia coli, and Lactococcus in the intestinal microbiota of piglets were significantly changed by PEDV infection. These results strengthen our understanding of viruses influencing intestinal microbes and remind us of the potential association between PEDV and intestinal microbes.


Assuntos
Infecções por Coronavirus/virologia , Microbioma Gastrointestinal , Vírus da Diarreia Epidêmica Suína/fisiologia , Doenças dos Suínos/virologia , Animais , Bactérias/classificação , Bactérias/genética , Bactérias/isolamento & purificação , Infecções por Coronavirus/microbiologia , Fezes/microbiologia , Intestinos/microbiologia , Vírus da Diarreia Epidêmica Suína/genética , Suínos , Doenças dos Suínos/microbiologia
14.
Acta Vet Scand ; 62(1): 41, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-32746868

RESUMO

BACKGROUND: Similar to the situation in other European countries, Danish wild boars may harbour a wide range of pathogens infectious to humans and domestic pigs. Although wild boars must be kept behind fences in Denmark, hunting and consumption of the meat may cause zoonotic transmission. Moreover, most infections of wild boars are transmissible to domestic pigs, which may have important economic consequences. The aim of this study was to investigate whether Danish wild boars were infected with bacteria and parasites transmissible to humans or domestic pigs: Brucella suis, methicillin-resistant Staphylococcus aureus (MRSA), Salmonella spp., Trichinella spp., lungworms and gastrointestinal parasites, especially Ascaris suum. This is the first study to investigate the prevalence of these important pathogens in Danish wild boars. RESULTS: Wild boars from eight enclosures were analysed over a 5-year period. All tested wild boars were negative for B. suis (n = 240), MRSA (n = 244), Salmonella spp. (n = 115) and Trichinella spp. (n = 232), while eight parasite genera were identified in the faeces (n = 254): Ascaris suum, Capillaria sp., Cystoisospora suis, Eimeria spp., Metastrongylus sp. (lungworm), Strongyloides ransomi, Trichuris suis and strongylid eggs, i.e. strongyles not identified to the genera. Eimeria spp. and Metastrongylus sp. had the highest prevalence (92.3 and 79.5%, respectively) and were identified in wild boars from all eight enclosures, while the remaining parasite genera were present more sporadically. CONCLUSIONS: Wild boars from Denmark constitute a low risk of transmitting B. suis, MRSA, Salmonella spp. and Trichinella spp. to humans or domestic pigs, while economically important parasites transmissible to domestic pigs are highly prevalent in the wild boar population.


Assuntos
Infecções Bacterianas/veterinária , Coccidiose/veterinária , Monitoramento Epidemiológico/veterinária , Helmintíase Animal/epidemiologia , Doenças dos Suínos/epidemiologia , Animais , Animais Selvagens , Infecções Bacterianas/epidemiologia , Infecções Bacterianas/microbiologia , Coccidiose/epidemiologia , Coccidiose/parasitologia , Dinamarca/epidemiologia , Feminino , Helmintíase Animal/parasitologia , Masculino , Prevalência , Sus scrofa , Suínos , Doenças dos Suínos/microbiologia , Doenças dos Suínos/parasitologia
15.
J Vet Sci ; 21(4): e54, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32735092

RESUMO

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a leading cause of severe infections in humans and animals worldwide. Studies elucidating the population structure, staphylococcal cassette chromosome mec types, resistance phenotypes, and virulence gene profiles of animal-associated MRSA are needed to understand spread and transmission. OBJECTIVES: The objective of this study was to determine 1) clonal complexes and spa types, 2) resistance phenotypes, and 3) virulence/resistance gene profiles of MRSA isolated from animals in Switzerland. METHODS: We analyzed 31 presumptive MRSA isolates collected from clinical infections in horses, dogs, cattle, sheep, and pigs, which had tested positive in the Staphaurex Latex Agglutination Test. The isolates were characterized by spa typing and DNA microarray profiling. In addition, we performed antimicrobial susceptibility testing using the VITEK 2 Compact system. RESULTS: Characterization of the 31 presumptive MRSA isolates revealed 3 methicillin-resistant Staphylococcus pseudintermedius isolates, which were able to grow on MRSA2 Brilliance agar. Of the 28 MRSA isolates, the majority was assigned to CC398 (86%), but CC8 (11%) and CC1 (4%) were also detected. The predominant spa type was t011 (n = 23), followed by t009 (n = 2), t034 (n = 1), t008 (n = 1), and t127 (n = 1). CONCLUSIONS: The results of this study extend the current body of knowledge on the population structure, resistance phenotypes, and virulence and resistance gene profiles of MRSA from livestock and companion animals.


Assuntos
Resistência Microbiana a Medicamentos/genética , Staphylococcus aureus Resistente à Meticilina/genética , Análise de Sequência com Séries de Oligonucleotídeos/veterinária , Infecções Estafilocócicas/veterinária , Animais , Bovinos , Doenças dos Bovinos/microbiologia , Doenças do Cão/microbiologia , Cães , Doenças dos Cavalos/microbiologia , Cavalos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Fenótipo , Ovinos , Doenças dos Ovinos/microbiologia , Infecções Estafilocócicas/microbiologia , Suínos , Doenças dos Suínos/microbiologia
16.
J Vet Sci ; 21(4): e57, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32735095

RESUMO

BACKGROUND: Streptococcus dysgalactiae subspecies equisimilis (SDSE) acts as an etiological agent for lameness, neurological signs, and high mortality in pigs. Despite its importance in pig industries and zoonotic potential, little is known about the effects of this pathogen. OBJECTIVES: This study aimed to determine the molecular characteristics and antimicrobial resistance of SDSE strains isolated from diseased pigs. METHODS: A total 11 SDSE isolates were obtained from diseased pigs. Bacterial identification, PCR for virulence genes, emm typing, and antimicrobial resistance genes, multilocus sequence typing, and antimicrobial susceptibility test were performed. RESULTS: Nine isolates were from piglets, and 8 showed lameness, sudden death, or neurological signs. The isolates were PCR-positive for sla (100%), sagA (100%), and scpA (45.5%), and only 1 isolate amplified the emm gene (stL2764). Eight different sequence types were detected, categorized into 2 clonal complexes and 4 singletons. All the isolates in this study were included in a small cluster, which also contained other strains derived from humans and horses. The minimum inhibitory concentrations for the tested beta-lactams were low, while those for macrolides, tetracyclines, and fluoroquinolones were relatively high. PCR analysis of the macrolide and tetracycline resistance genes demonstrated that the isolates carried erm(B) (18.2%, n = 2), mef(A/E) (9.1%, n = 1), tet(M) (18.2%, n = 2), and tet(O) (90.2%, n = 10). Two isolates presented a mutation in parC, which is associated with fluoroquinolone resistance. CONCLUSION: This study provided insight into swine-derived SDSE, as it is related to veterinary medicine, and elucidated its zoonotic potential, in the context of molecular epidemiology and antimicrobial resistance in public health.


Assuntos
Farmacorresistência Bacteriana/genética , Infecções Estreptocócicas/veterinária , Streptococcus/efeitos dos fármacos , Doenças dos Suínos/diagnóstico , Animais , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana/veterinária , Tipagem de Sequências Multilocus/veterinária , República da Coreia , Infecções Estreptocócicas/diagnóstico , Infecções Estreptocócicas/microbiologia , Streptococcus/genética , Suínos , Doenças dos Suínos/microbiologia
17.
Appl Environ Microbiol ; 86(21)2020 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-32859592

RESUMO

Salmonella enterica serovar Typhimurium is a prevalent incitant of enteritis in human beings and nonhuman animals. It has been proposed that host defense responses incited by Salmonella allow the bacterium to overcome colonization resistance. Piglets (n = 24) were orally inoculated with S. enterica serovar Typhimurium DT104 or buffer alone, and the host and microbial responses were temporally examined at the acute (2 days postinoculation [dpi]), subacute (6 dpi), and recovery (10 dpi) stages of salmonellosis. At the acute stage of disease, body temperatures were elevated, and feed consumption and weight gain were reduced. The densities of Salmonella associated with the gut mucosa decreased over time, with higher densities of the bacterium in the ileum and the large intestine. Moreover, substantive histopathological changes were observed as a function of time, with prominent epithelial injury and neutrophil infiltration observed at 2 dpi. Correspondingly, a variety of host metrics were temporally affected in piglets with salmonellosis (e.g., TNFα, IFNγ, PR39, ßD2, iNOS, IL8, REGIIIγ). The enteric microbiota was characterized using culture-independent and -dependent methods in concert, and taxon- and location-specific changes to the microbiota were observed in infected piglets. Bacteroides spp. (e.g., Bacteroides uniformis, Bacteroides fragilis), Streptococcus spp. (e.g., Streptococcus gallolyticus), and various Gammaproteobacteria were highly associated with inflamed tissues, while bacteria within the Ruminococcaceae and Veillonellaceae families were mainly associated with healthy mucosae. In conclusion, the study findings showed that S Typhimurium incited temporal and spatial modifications to the swine autochthonous microbiota, and to host defense responses, that were consistent with overcoming colonization resistance to incite salmonellosis in swine.IMPORTANCE Limited information is available on host and enteric microbiota responses incited by Salmonella enterica serovar Typhimurium in swine and on possible mechanisms by which the bacterium overcomes colonization resistance to incite salmonellosis. Temporal characterization of a variety of host metrics in piglets (e.g., physiological, histopathological, and immunological) showed the importance of studying the progression of salmonellosis. A number of host responses integrally associated with disease development were identified. Utilization of next-generation sequence analysis to characterize the enteric microbiota was found to lack sufficient resolution; however, culture-dependent and -independent methods in combination identified taxon- and location-specific changes to bacterial communities in infected piglets. The study identified bacterial and host responses associated with salmonellosis, which will be beneficial in understanding colonization resistance and in the development of effective alternatives to antibiotics to mitigate salmonellosis.


Assuntos
Ceco/microbiologia , Colo/microbiologia , Microbioma Gastrointestinal , Interações entre Hospedeiro e Microrganismos/imunologia , Íleo/microbiologia , Salmonella typhimurium/fisiologia , Animais , Ceco/imunologia , Colo/imunologia , Íleo/imunologia , Masculino , Distribuição Aleatória , Salmonelose Animal/imunologia , Salmonelose Animal/microbiologia , Suínos , Doenças dos Suínos/imunologia , Doenças dos Suínos/microbiologia , Fatores de Tempo
18.
J Anim Sci ; 98(8)2020 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-32717077

RESUMO

Developments of pulmonary diseases, often accompanied by infections of bacteria, severely affect the meat production and welfare of pigs. This study investigated 307 pigs at age of 240 d from an eight-breed cross reared under standardized housing conditions for associations among the extent of lung lesions, bacteria load inferred from 16S rRNA sequencing of bronchoalveolar lavage fluid, as well as 57 immune cells and 25 hematological traits. We showed that the pigs under study suffered substantial and varied lung lesions, and the Mycoplasma is the most associated bacteria genera. At a false discovery rate of 0.05 (FDR < 0.05), the severity of lung lesions were significantly associated with greater CD8+ to CD3+ cell ratio, neutrophil-to-lymphocyte ratio (NLR), and standard deviation of red blood cell volume distribution width (RDW-SD), and lower CD4-CD8-/CD3+, CD3+CD4-CD8-/PBMCs (peripheral blood mononuclear cells) and CD14-CD16-/PBMCs cell ratios, mean corpuscular hemoglobin concentration, lymphocyte count, and lymphocyte count percentage, reflecting an status of inflammation, immune suppression, and hypoxia of the pigs accompanying the progression of the lung lesions. The Mycoplasma abundance showed positive correlations with neutrophil count, neutrophil count percentage, NLR, monocyte count, coefficient of variation in red blood cell volume distribution width , and RDW-SD, and negative correlations with mean corpuscular hemoglobin concentration, lymphocyte count, and lymphocyte count percentage; these correlations are largely consistent with those of lung lesions, supporting the comorbidity of lung lesions and Mycoplasma infection. We also observed nonlinear associations that sharp increases in neutrophil count and neutrophil count percentage occurred only when Mycoplasma abundance raised above the population-average level. The results provide helpful insights into the changes of host immune status in response to Mycoplasma relevant lung diseases in pigs.


Assuntos
Carga Bacteriana , Infecções por Mycoplasma/veterinária , Doenças dos Suínos/microbiologia , Animais , Índices de Eritrócitos/veterinária , Predisposição Genética para Doença , Inflamação/patologia , Inflamação/veterinária , Contagem de Leucócitos/veterinária , Leucócitos Mononucleares , Pulmão/patologia , Contagem de Linfócitos/veterinária , Linfócitos , Mycoplasma/imunologia , Infecções por Mycoplasma/genética , Infecções por Mycoplasma/microbiologia , Infecções por Mycoplasma/patologia , Neutrófilos , RNA Ribossômico 16S , Suínos , Doenças dos Suínos/genética , Doenças dos Suínos/patologia
19.
Arch Microbiol ; 202(9): 2499-2508, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32638056

RESUMO

Haemophilus parasuis (H. parasuis), the cause of the Glasser's disease, is a potentially pathogenic gram-negative organism that colonizes the upper respiratory tract of pigs. The extraction of Blumea balsamifera DC., as a traditional Chinese herb, has shown great bacteriostatic effect against several common bacteria. To study the antibacterial effect on H. parasuis in vitro, this study evaluated the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of Blumea balsamifera DC. essential oil (BBO) as well as morphological changes in H. parasuis treated with it. Furthermore, changes in expression of total protein and key virulence factors were also assessed. Results showed that the MIC and MBC were 0.625 and 1.25 µg/mL, respectively. As the concentration of BBO increased, the growth curve inhibition became stronger. H. parasuis cells were damaged severely after treatment with BBO for 4 h, demonstrating plasmolysis and enlarged vacuoles, along with broken cell walls and membranes. Total protein and virulence factor expression in H. parasuis was significantly downregulated by BBO. Taken together, these results indicated a substantial antibacterial effect of BBO on H. parasuis.


Assuntos
Asteraceae/química , Haemophilus parasuis/efeitos dos fármacos , Óleos Voláteis/farmacologia , Animais , Antibacterianos/farmacologia , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Infecções por Haemophilus/tratamento farmacológico , Haemophilus parasuis/genética , Testes de Sensibilidade Microbiana , Suínos , Doenças dos Suínos/tratamento farmacológico , Doenças dos Suínos/microbiologia , Fatores de Virulência/genética
20.
Acta Vet Scand ; 62(1): 35, 2020 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-32580726

RESUMO

BACKGROUND: Respiratory diseases are major health concerns in the pig production sector worldwide, contributing adversely to morbidity and mortality. Over the past years there was a rise in reported incidents of respiratory disease in pigs in Norway, despite population wide freedom from Aujeszky´s disease, porcine reproductive and respiratory syndrome, porcine respiratory corona virus and enzootic pneumonia. The main objective of this study was to investigate acute outbreaks of respiratory disease in conventional Norwegian fattening pig herds. The study included 14 herds. In seven herds with reported outbreaks of acute respiratory disease, data on clinical signs was recorded and samples for laboratory examination were collected. Diagnostic protocols were compared by parallel analysis of clinically healthy pigs from seven non-outbreak herds. RESULTS: The most commonly reported clinical signs were sudden deaths and dyspnea. An average compartment morbidity of 60%, mortality of 4% and case fatality of 9% was recorded in the outbreak herds. Post-mortem examinations revealed acute lesions resembling porcine pleuropneumonia in all 28 pigs investigated from the outbreak herds and in 2 of the 24 (8%) pigs from the non-outbreak herds. Chronic lesions were recorded in another 2 pigs (8%) from the non-outbreak herds. Actinobacillus pleuropneumoniae serovar 8 was isolated from lungs and/or pleura from all tested pigs (n = 28) in the outbreak herds, and from 2 out of 24 pigs (8%) in the non-outbreak herds, one pig with an acute and another pig with a chronic infection. No other significant bacterial findings were made. Seroconversion to A. pleuropneumoniae antibodies was detectable in all outbreak herds analyzed and in six out of seven non-outbreak herds, but the risk ratio for seroconversion of individual pigs was higher (risk ratio 2.3 [1.50- 3.43 95% CI; P < 0.001]) in the outbreak herds. All herds tested positive for porcine circovirus type 2 and negative for influenza A viruses on oral fluid RT-qPCR. CONCLUSION: The main etiological pathogen found during acute outbreaks of respiratory disease was A. pleuropneumoniae serovar 8. All pigs from outbreak herds had typical lesions of acute porcine pleuropneumonia, and only A. pleuropneumoniae serovar 8 was identified. Co-infections were not found to impact disease development.


Assuntos
Doença Aguda/epidemiologia , Surtos de Doenças/veterinária , Doenças Respiratórias/veterinária , Doenças dos Suínos/epidemiologia , Animais , Noruega/epidemiologia , Doenças Respiratórias/epidemiologia , Doenças Respiratórias/microbiologia , Doenças Respiratórias/virologia , Sus scrofa , Suínos , Doenças dos Suínos/microbiologia , Doenças dos Suínos/virologia
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