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1.
Acta Vet Scand ; 61(1): 41, 2019 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-31455410

RESUMO

BACKGROUND: Villegas-Glisson/University of Georgia (VG/GA) strain of Newcastle disease virus (NDV) is recommended for the initial vaccination of commercially reared turkey poults. However, the vaccine-induced antibody responses have not been studied in this species. The level of systemic humoral immune responses against the NDV was investigated in commercial turkey poults vaccinated with the VG/GA vaccine. One hundred eighty-two hybrid strain of turkey poults (Meleagris gallopavo) were divided randomly into vaccinated and unvaccinated groups. The vaccinated group was given the VG/GA vaccine at 10 and 20 days of age. To investigate the vaccine immunity, the level of specific IgY and IgA in serum samples were determined using ELISA and haemagglutination inhibition assays (HI). The biological half-life of maternal antibodies was also determined before the immunization. RESULTS: VG/GA-specific antibodies were detected in the vaccinated turkey poults and were significantly higher in the vaccinated group compared to the unvaccinated group. IgY and IgA antibodies showed a significant increase in titers 14 days after the second vaccination and reached a peak on day 35 of age. The correlation coefficient and intra-rater reliability showed a significant correlation between the HI titers and IgY/IgA ELISA values. Maternal IgY and IgA levels were found to decline in the serum with half-lifes of 7.68 ± 2.35 and 2.18 ± 0.82 days, respectively. CONCLUSIONS: Enterotropic lentogenic VG/GA vaccine induced a marked humoral immune response against the NDV in turkey poults. The positive correlation between IgY and IgA highlights the role of these two antibody classes in controlling the Newcastle disease in turkey poults.


Assuntos
Imunidade Humoral/imunologia , Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/imunologia , Perus , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/sangue , Doença de Newcastle/prevenção & controle , Doenças das Aves Domésticas/prevenção & controle
2.
Parasit Vectors ; 12(1): 347, 2019 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-31300007

RESUMO

BACKGROUND: Live anticoccidial vaccines have been a tremendous success for disease prevention. The establishment of the reverse genetic manipulation platform has enabled the development of Eimeria parasites, the live anticoccidial vaccine strains, as vaccine vectors. In our previous study, recombinant E. tenella expressing a single immunodominant antigen of E. maxima (Et-EmIMP1) was able to protect chickens against challenge infection with E. maxima. This promising result encouraged us to further explore strategies to improve the protection efficacy of recombinant Eimeria and develop it as a vaccine vector. RESULTS: We constructed a novel recombinant Eimeria line expressing apical membrane antigen 1 of E. maxima (Et-EmAMA1) and then immunized chickens with Et-EmAMA1 and/or Et-EmIMP1. We found that the E. maxima soluble antigen-specific cell-mediated immunity was much stronger in the birds that were co-immunized with Et-EmAMA1 and Et-EmIMP1 than in those that were immunized with Et-EmAMA1 or Et-EmIMP1 alone. The oocyst production after E. maxima infection was significantly reduced in the recombinant Eimeria-immunized birds compared with the wild-type-immunized and naïve birds. The oocyst production in the birds co-immunized with Et-EmAMA1 and Et-EmIMP1 was consistently the lowest among the treatment groups after E. maxima infection. CONCLUSIONS: These results demonstrated that Eimeria is an effective vaccine vector that can carry and deliver heterologous Eimeria antigens to the host immune system and trigger specific immune responses. Our results also suggested that increasing the number of recombinant Eimeria lines is an effective approach to enhance protective immunity against infections with heterologous pathogens.


Assuntos
Coccidiose/veterinária , Eimeria tenella/genética , Eimeria/genética , Imunidade Celular , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/imunologia , Animais , Antígenos de Protozoários/imunologia , Galinhas , Coccidiose/prevenção & controle , Eimeria/imunologia , Eimeria tenella/imunologia , Doenças das Aves Domésticas/imunologia , Organismos Livres de Patógenos Específicos , Vacinas Atenuadas , Vacinas Sintéticas
3.
Vet Microbiol ; 235: 136-142, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282371

RESUMO

Infectious Bursal Disease Virus (IBDV) of the ITA genotype (G6) was shown to have peculiar molecular characteristics and, despite a subclinical course, aggressiveness towards lymphoid tissues after experimental infection of specific-pathogen-free (SPF) chickens. The aim of the present study was to evaluate and compare with a Classical IBDV strain, ITA IBDV distribution and persistence in various tissues (bursa of Fabricious, spleen, thymus, bone marrow, caecal tonsils, Harderian gland, kidney, liver and proventriculus), its cloacal shedding and the involvement of gut TLR-3 in duodenum tissues. The 35-day-old SPF chickens were experimentally infected and sampled up to 28 days post infection (dpi) for IBDV detection and TLR-3 quantification by qRT-PCR. The ITA IBDV strain was detected in lymphoid and most non-lymphoid tissues up to the end of the trial, with higher loads compared to the Classical IBDV. Most of those differences were found during the first 2 weeks post-infection. Notably, bone marrow and caecal tonsils presented higher viral loads until 28 dpi, allowing to speculate that these organs may serve as non-bursal lymphoid tissues supporting virus replication. Differences in relative TLR-3 gene expression between ITA IBDV-infected birds and Classical-IBDV infected ones were observed at 4, 14 and 21 dpi, being initially higher in Classical group and later in ITA group. Our results provide new insights into IBDV pathogenesis showing that IBDV of ITA genotype leads to a high and persistent viral load in lymphoid tissues and to a delayed antiviral response.


Assuntos
Infecções por Birnaviridae/veterinária , Vírus da Doença Infecciosa da Bursa/genética , Tecido Linfoide/virologia , Doenças das Aves Domésticas/imunologia , Carga Viral , Animais , Infecções por Birnaviridae/imunologia , Medula Óssea/patologia , Medula Óssea/virologia , Galinhas , Ensaio de Imunoadsorção Enzimática , Genótipo , Vírus da Doença Infecciosa da Bursa/patogenicidade , Tonsila Palatina/virologia , Doenças das Aves Domésticas/virologia , Organismos Livres de Patógenos Específicos , Receptor 3 Toll-Like/genética , Replicação Viral
4.
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
5.
Vet Immunol Immunopathol ; 212: 15-22, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31213247

RESUMO

Marek's disease virus (MDV), an α-herpesvirus targeting avian species, causes fatal Marek's disease (MD) in chickens. The host interferon (IFN) responses play a key role in resisting viral infection. However, host IFN responses following MDV infection in the chicken central immune organs (thymus and bursa of Fabricius), which contain numerous MDV target cells, is poorly understood. In this study, we performed animal experiments in specific pathogen-free chickens infected with two virulent MDV strains (BS/15 and Md5) or without infection as negative controls. Specifically, the type I IFN (IFN-α and IFN-ß) transcriptional and proteomic expression levels at 7, 10, 14, 17, and 21 days post infection (dpi) were detected and analyzed. Our results indicated that the mRNA and protein expression levels of IFN-α and IFN-ß in the thymus and bursa of Fabricius were mainly downregulated in cytolytic infection (such as 10 dpi) and reactivation (such as 17 dpi) stages, but not the latent (such as 14 dpi) stage of MDV infection, which was determined by comprehensively analyzing the MDV viral load and immune organ damage caused by MDV infection. These data suggest that MDV could inhibit the expression of host type I IFNs, which may be involved in the MDV-induced host immunosuppression and contribute to the immune escape of MDV from host immunity. Furthermore, we found that the downregulated expression of the host type I IFNs induced by BS/15 and Md5 infection was significantly different, which we speculated may be related to the diverse virulence and pathogenicity of MDV strains. In conclusion, our study demonstrated that MDV mostly inhibited the expression of type I IFNs in infected hosts, which may be associated to its pathogenesis.


Assuntos
Interferon Tipo I/imunologia , Doença de Marek/imunologia , Doenças das Aves Domésticas/imunologia , Animais , Bolsa de Fabricius/imunologia , Galinhas , Expressão Gênica , Herpesvirus Galináceo 2 , Interferon Tipo I/genética , Interferon-alfa/genética , Interferon-alfa/imunologia , Interferon beta/genética , Interferon beta/imunologia , Doenças das Aves Domésticas/virologia , Proteômica , RNA Mensageiro/genética , Organismos Livres de Patógenos Específicos , Timo/imunologia , Carga Viral , Virulência
6.
Vet Immunol Immunopathol ; 212: 9-14, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31213252

RESUMO

Targeting antigens to endocytic receptors on the surface of dendritic cells is a new strategy for increasing the adaptive immune response. The objective of the current study was the construction and bacterial expression of a recombinant antibody single-chain fragment variable (ScFv) directed against chicken DEC 205, an endocytic receptor, for use in the genetic fusion of antigens. In particular, we use as antigen the hemagglutinin-neuraminidase (HN) of Newcastle disease virus. Our results show that inoculation of chickens with HN genetically fused to the ScFv anti-DEC 205 induced an evidently higher immune response against HN, in contrast to inoculation with unconjugated HN. In addition, neutralizing antibodies against Newcastle disease virus were detected only in the serum from chickens immunized with HN fused to ScFv anti-DEC 205. Inoculated fused antigens to ScFv against endocytic receptor DEC 205 resulted in a greater antibody-specific anti-HN production compared with antigens applied alone. The results of this study show that the strategy described here has the potential to be used in the development of more effective vaccines against infectious diseases in chickens.


Assuntos
Antígenos CD/imunologia , Lectinas Tipo C/imunologia , Antígenos de Histocompatibilidade Menor/imunologia , Vírus da Doença de Newcastle/enzimologia , Doenças das Aves Domésticas/prevenção & controle , Receptores de Superfície Celular/imunologia , Anticorpos de Cadeia Única/biossíntese , Animais , Anticorpos Neutralizantes/sangue , Anticorpos Antivirais/sangue , Galinhas/imunologia , Escherichia coli/genética , Hemaglutininas Virais/imunologia , Neuraminidase/imunologia , Doenças das Aves Domésticas/imunologia , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/imunologia , Anticorpos de Cadeia Única/imunologia , Vacinas Virais/imunologia
7.
Parasitol Res ; 118(6): 1701-1710, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31065831

RESUMO

Coccidiosis is a major poultry disease which compromises animal welfare and costs the global chicken industry a huge economic loss. As a result, research entailing coccidial control measures is crucial. Coccidiosis is caused by Eimeria parasites that are highly immunogenic. Consequently, a low dosage of the Eimeria parasite supplied by a vaccine will enable the host organism to develop an innate immune response towards the pathogen. The production of traditional live anticoccidial vaccines is limited by their low reproductive index and high production costs, among other factors. Recombinant vaccines overcome these limitations by eliciting undesired contaminants and prevent the reversal of toxoids back to their original toxigenic form. Recombinant vaccines are produced using defined Eimeria antigens and harmless adjuvants. Thus, studies regarding the identification of potent novel Eimeria antigens which stimulate both cell-mediated and humoral immune responses in chickens are essential. Although the prevalence and risk posed by Eimeria have been well established, there is a dearth of information on genetic and antigenic diversity within the field. Therefore, this paper discusses the potential and efficiency of recombinant vaccines as an anticoccidial control measure. Novel protective Eimeria antigens and their antigenic diversity for the production of cheap, easily accessible recombinant vaccines are also reviewed.


Assuntos
Coccidiose/veterinária , Eimeria/imunologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/imunologia , Adjuvantes Imunológicos , Animais , Antígenos/administração & dosagem , Antígenos/genética , Antígenos/imunologia , Galinhas/parasitologia , Coccidiose/imunologia , Coccidiose/parasitologia , Coccidiose/prevenção & controle , Eimeria/genética , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/parasitologia , Vacinas Protozoárias/administração & dosagem , Vacinas Protozoárias/genética
8.
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
9.
Vet Microbiol ; 231: 214-217, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955812

RESUMO

In this study, a recombinant ALV with ALV-K env and ALV-J backbone was generated (designated ALV-K-env-J) and tested in vitro and in vivo. The growth curve in DF1 cells showed that the recombinant virus replicated more efficiently in comparison with the ALV-J and ALV-K. Although all the infected chickens showed growth retardation compared with the non-infected chickens, the viral and serological detection showed that the positive rate and virus load detected in blood and cloaca, and the positive rate and titer of antibody against p27 from the chickens infected with ALV-K-env-J were higher than those from the chickens infected with the ALV-K, but less than those from the chickens infected with the ALV-J. All these data clearly demonstrated that the recombination event in this study increased the pathogenesis of ALV-K, and the potential recombination between different ALV subgroups should be worried when the clinical co-infections occur.


Assuntos
Vírus da Leucose Aviária/genética , Vírus da Leucose Aviária/patogenicidade , Leucose Aviária/virologia , Doenças das Aves Domésticas/virologia , Recombinação Genética , Animais , Anticorpos Antivirais/sangue , Leucose Aviária/imunologia , Galinhas/virologia , Cloaca/virologia , Doenças das Aves Domésticas/imunologia , Testes Sorológicos , Carga Viral
10.
Vet Microbiol ; 231: 24-32, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955817

RESUMO

Avian influenza virus (AIV) H9N2 infection causes economic losses on poultry farms, and immunostimulants are essential for improving chicken immunity. This study evaluated the immunological and pathological effects of vitamin E with Fetomune Plus® (a commercial product based on a yeast extract and vitamins) on chickens experimentally infected with AIV H9N2. Three groups of white Hy-Line chicks were included. The G1 group was kept as an uninfected untreated control, the G2 group was intranasally infected with the AIV H9N2 strain (0.5 ml of 106 50% egg infectious dose (EID50)), and the G3 group was infected and treated with vitamin E (200 mg/kg of diet) and Fetomune Plus® (1 ml/liter of drinking water) for four weeks. The gene expression of interferon-gamma (IFN-γ), interleukin (IL)-6, and IL-2 was determined at 3, 5 and 7 days post-infection (PI). Virus shedding titers and rates and haemagglutination inhibition (HI) antibody titers were detected. Clinical signs, mortalities and post-mortem lesions were recorded. The birds were weighed, and relative organ weights were calculated. Tissue specimens were taken for histopathological examination and immunohistochemistry (IHC). The expression of IFN-γ in the duodenum revealed a significant increase in G2 compared to G3 at 3 days PI, while the duodenal and splenic expression of IL-6 was significantly increased in G2 compared to G3 at 5 days PI. IL-2 was overexpressed in the duodenum in G3 compared to G2 at 3 and 5 days PI. A significant decrease (P ≤ 0.05) in the virus shedding titer and an increase in the HI titers were detected in G3 compared to G2. The clinical signs and the mortality rate were clearly appeared in G2 than in G3. By IHC, lower H9N2 staining intensity was observed in the examined organs from G3 than in those from G2. In conclusion, as a first report, vitamin E with Fetomune Plus® supplementation for four weeks could improve the immunological and pathological effects of H9N2 infection on chickens.


Assuntos
Suplementos Nutricionais , Influenza Aviária/terapia , Doenças das Aves Domésticas/terapia , Vitamina E/imunologia , Ração Animal , Animais , Anticorpos Antivirais/sangue , Galinhas , Citocinas/imunologia , Testes de Inibição da Hemaglutinação , Imuno-Histoquímica , Vírus da Influenza A Subtipo H9N2 , Influenza Aviária/imunologia , Interferon gama/imunologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologia , Eliminação de Partículas Virais/efeitos dos fármacos , Vitamina E/administração & dosagem
11.
Vet Microbiol ; 231: 48-55, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955823

RESUMO

Mycoplasma synoviae (MS) is a major pathogen of poultry globally, causing chronic respiratory disease and arthritis. Vaccination is an effective means for the control of the disease. The MS-H vaccine is an attenuated strain developed through chemical mutagenesis of an Australian field strain, 86079/7NS. Analysis of whole genome of MS-H and its comparison with that of 86079/7NS has revealed a frameshift mutation early in a gene (oppF) that codes for an oligopeptide transporter permease, OppF. Monospecific antibodies raised against peptides upstream and downstream of the mutation in OppF revealed that only N-terminus of the OppF was expressed in MS-H while the full version was expressed in 86079/7NS. Also, examination of the recombinant N- (OppF-N) and C termini (OppF-C) of OppF, upstream and downstream of the mutation site respectively, as well as the full length OppF in Western immunoblotting experiments showed that serum from MS-H vaccinated chicken strongly bound OppF-N while serum from 86079/7NS challenged chicken detected OppF, OppF-N and OppF-C. The potential of the recombinant OppF, OppF-N and OppF-C to discriminate antibody responses to MS-H reisolates with wild or vaccine type OppF was assessed against 88 chicken sera in indirect ELISA and ratios were calculated between optical densities (OD) over those obtained in MS major membrane protein MSPB ELISA. Comparison of the OD ratios revealed that the MSPB/OppF and MSPB/OppF-C OD ratios of the sera against isolates with vaccine type OppF were significantly higher than those against isolates with wild type OppF. These results are in accordance with oppF gene mutation in MS-H and confirms that MS-H does not express OppF beyond the frame shift mutation found in its oppF gene. Also, the indirect ELISA based on OppF-C in combination with the MSPB has the potential to differentiate between MS-H and field strain antibody responses.


Assuntos
Proteínas de Bactérias/genética , Vacinas Bacterianas/imunologia , Mutação , Infecções por Mycoplasma/veterinária , Mycoplasma synoviae/genética , Doenças das Aves Domésticas/imunologia , Animais , Anticorpos Antibacterianos/sangue , Austrália , Proteínas de Bactérias/imunologia , Galinhas , Ensaio de Imunoadsorção Enzimática , Infecções por Mycoplasma/imunologia , Infecções por Mycoplasma/prevenção & controle , Mycoplasma synoviae/imunologia , Doenças das Aves Domésticas/prevenção & controle , Testes Sorológicos , Vacinas Atenuadas/imunologia
12.
Anim Genet ; 50(4): 403-406, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31017703

RESUMO

Pullorum is a bacterial disease that threatens the modern poultry industry. Over the years, research on this topic has focused mainly on its epidemiology, whereas the hosts' genetic basis of infection is still vague. In order to identify chickens' genes associated with pullorum, we sequenced 300 New Pudong chicken by double digest genotyping-by-sequencing. We obtained 1 527 953 SNPs for a genome-wide association analysis, which identified 43 genome-wide significant markers. Most of the significant SNPs were in the interval of 57.7-59.0 Mb on chromosome 5. The gene set enrichment analysis suggests a potential manner for bacterial infection and remaining inside the host. This work provides basic data for the purification, prevention and treatment of pullorum disease.


Assuntos
Galinhas , Doenças das Aves Domésticas/genética , Salmonelose Animal/genética , Salmonella/fisiologia , Animais , Cromossomos , Suscetibilidade a Doenças , Polimorfismo de Nucleotídeo Único , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/prevenção & controle , Salmonelose Animal/imunologia , Salmonelose Animal/prevenção & controle
13.
Poult Sci ; 98(8): 3165-3175, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30968116

RESUMO

Ammonia (NH3) is a harmful gas with irritating odor, and higher NH3 concentration was found in intensive poultry houses. Although the toxicity of NH3 is well known, little attention has been given to the mechanism of NH3 poisoning in chicken immune organs. To investigate NH3-caused inflammatory damage of broiler spleens, in this study, a broiler model for NH3 poisoning was established, and 3 levels (including microRNA [miRNA], mRNA, and protein) were performed using qRT-PCR and western blot. The results indicated that NH3 exposure caused inflammatory damage using microstructure observation; decreased 2 inflammation-related miRNAs (miR-133a and miR-6615), 2 cytokines secreted by T helper cells 1 (Th1), and heme oxygenase-1 (HO-1); and increased 2 target genes (LOC101747543 and mothers against decapentaplegic homolog 7 [SMAD7]) of the 2 miRNAs, 7 inflammation-related factors, 3 cytokines secreted by Th2, and 5 heat shock proteins (HSPs) in broiler spleens. Our study suggested that Th1/Th2 imbalance, nuclear factor-κB (NF-κB) pathway, and compensatory response of HSPs were involved in NH3-caused inflammatory damage in broiler spleens; there was immunotoxic effect in excess NH3 on broilers. For the first time, we discovered miR-6615 and LOC101747543 may be involved in the mechanism of broiler spleen inflammatory damage caused by NH3 via the NF-κB pathway, and further mechanism needs to be investigated. This study provides new insights for NH3 toxicity identification and risk assessment in animal husbandry production practice.


Assuntos
Amônia/toxicidade , Inflamação/veterinária , Doenças das Aves Domésticas/induzido quimicamente , Baço/patologia , Poluentes Atmosféricos/toxicidade , Poluição do Ar em Ambientes Fechados/efeitos adversos , Criação de Animais Domésticos , Animais , Galinhas , Citocinas/metabolismo , Proteínas de Choque Térmico/metabolismo , Inflamação/induzido quimicamente , Inflamação/genética , Inflamação/patologia , MicroRNAs , NF-kappa B , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/patologia , RNA Mensageiro , Transdução de Sinais , Baço/imunologia
14.
Vet Immunol Immunopathol ; 210: 6-14, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30947981

RESUMO

Consumption of contaminated poultry products is one of the main sources of human campylobacteriosis, of which Campylobacter jejuni subsp. jejuni (C. jejuni) is responsible for approximately 90% of the cases. At slaughter, the ceca of commercial chickens and turkeys are the main anatomical site where C. jejuni asymptomatically colonizes. We have previously colonized commercial turkey poults with different isolates of C. jejuni and evaluated different media to best enumerate Campylobacter from intestinal samples, but the host-response is unknown in turkeys. Enumeration of Campylobacter (colony forming units (cfu)/gram of intestinal contents) can be challenging, and can be confounded if animals are colonized with multiple species of Campylobacter. In order to precisely enumerate the C. jejuni isolate used to experimentally colonize turkeys, constructs of C. jejuni (NCTC 11,168) were tagged with different antibiotic resistance markers at the CmeF locus (chloramphenicol (CjCm) or kanamycin (CjK)). We sought to examine the kinetics of intestinal colonization using the antibiotic resistant constructs, and characterize the immune response in cecal tissue of turkeys. In vitro analysis of the tagged antibiotic-resistant constructs demonstrated no changes in motility, morphology, or adherence and invasion of INT-407 cells compared to the parent isolate NCTC 11,168. Two animal experiments were completed to evaluate intestinal colonization by the constructs. In experiment 1, three-week old poults were colonized after oral gavage for 14 days, and CjCm and CjK cfu were recovered from cecal, but not ileal contents. In experiment 2, nine-week old poults were orally inoculated with CjCm, and the abundance of CjCm cfu/g of cecal contents significantly decreased beyond 14 days after inoculation. Significant lesions were detected in CjCm colonized poults at day 2 post-colonization. Using immunohistochemistry, Campylobacter antigen was detected in between cecal villi by day 7 of CjCm colonized poults. Quantitative RT-PCR of CjCm-colonized cecal tissue demonstrated significant down-regulation of IL-1ß, IL-10 and IL-13 mRNA, and significant up-regulation of IL-6, IL-8, IL-17 A, IL-22 and IFNγ mRNA on day 2, and for some on day 7 post-colonization. All differentially expressed genes were similar to mock-infected poults by day 14. These data suggest that C. jejuni induced a brief inflammatory response in the cecum of poults that quickly resolved. Results from this study provide valuable insight into host-response and persistent colonization of the turkey cecum. These findings will help to develop and test strategies to promote food safety in commercial turkeys.


Assuntos
Infecções por Campylobacter/veterinária , Campylobacter jejuni/genética , Resistência Microbiana a Medicamentos/genética , Mucosa Intestinal/imunologia , Intestinos/microbiologia , Animais , Infecções por Campylobacter/imunologia , Ceco/imunologia , Ceco/microbiologia , Contagem de Colônia Microbiana , Citocinas/genética , Microbiologia de Alimentos , Marcadores Genéticos , Interações entre Hospedeiro e Microrganismos/imunologia , Íleo/imunologia , Íleo/microbiologia , Inflamação , Intestinos/imunologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/microbiologia , Perus , Vacinação/veterinária
15.
Res Vet Sci ; 124: 256-262, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30999161

RESUMO

Interferon-induced proteins with tetratricopeptide repeats (IFITs) are a family of proteins strongly induced downstream of type I interferon signaling. The function of IFITs has been investigated extensively in mammals. IFIT5 is the sole protein in this family found in birds and little information is available about the function of avian IFIT5. In this study, duck IFIT5 was cloned from peripheral blood mononuclear cells. Multiple amino acid sequence alignment and phylogenetic analysis showed that duck IFIT5 is highly homologous to chicken IFIT5. Tissue specificity analysis demonstrated that duck IFIT5 was ubiquitously expressed in all examined tissues of five-day-old ducklings, with the highest expression levels in heart, followed by thymus, cerebrum, liver, and lung; kidney expressed the lowest. Quantitative real-time PCR (qRT-PCR) analysis revealed that duck IFIT5 expression rapidly increased both in vitro and in vivo after stimulation with polyinosinic:polycytidylic acid [poly (I:C)] and infection with virulent duck hepatitis A virus type 3 (DHAV-3), respectively. Altogether, these results indicate that the expression of duck IFIT5 is positively correlated with viral load and may play an important role in the immune response to DHAV-3 infection. This study lays a foundation for further research into the innate antiviral immune responses of ducklings.


Assuntos
Patos/genética , Patos/imunologia , Proteínas de Neoplasias/genética , Sequência de Aminoácidos , Animais , Animais Recém-Nascidos/genética , Animais Recém-Nascidos/imunologia , Proteínas Aviárias/química , Proteínas Aviárias/genética , Proteínas Aviárias/metabolismo , Sequência de Bases , Clonagem Molecular , Vírus da Hepatite do Pato/fisiologia , Hepatite Viral Animal/imunologia , Proteínas de Neoplasias/química , Proteínas de Neoplasias/metabolismo , Fases de Leitura Aberta , Filogenia , Infecções por Picornaviridae/imunologia , Infecções por Picornaviridae/veterinária , Poli I-C/farmacologia , Doenças das Aves Domésticas/imunologia , Alinhamento de Sequência
16.
J Vet Med Sci ; 81(4): 612-619, 2019 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-30867350

RESUMO

In this study, we evaluated antibody and cell-mediated immune (CMI) responses in the mucosal and systemic compartments and protection against challenge with a nephropathogenic Brazilian (BR-I) strain of infectious bronchitis virus (IBV) in chickens submitted to a vaccination regime comprising a priming dose of heterologous live attenuated Massachusetts vaccine followed by a booster dose of an experimental homologous inactivated vaccine two weeks later. This immunization protocol elicited significant increases in serum and lachrymal levels of anti-IBV IgG antibodies and upregulated the expression of CMI response genes, such as those encoding CD8ß chain and Granzyme homolog A in tracheal and kidney tissues at 3, 7, and 11 days post-infection in the vaccinated chickens. Additionally, vaccinated and challenged chickens showed reduced viral loads and microscopic lesion counts in tracheal and kidney tissues, and their antibody and CMI responses were negatively correlated with viral loads in the trachea and kidney. In conclusion, the combination of live attenuated vaccine containing the Massachusetts strain with a booster dose of an inactivated vaccine, containing a BR-I IBV strain, confers effective protection against infection with nephropathogenic homologous IBV strain because of the induction of consistent memory immune responses mediated by IgG antibodies and TCD8 cells in the mucosal and systemic compartments of chickens submitted to this vaccination regime.


Assuntos
Galinhas , Infecções por Coronavirus/imunologia , Imunogenicidade da Vacina , Memória Imunológica , Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas/virologia , Vacinas Virais/imunologia , Animais , Anticorpos Antivirais/imunologia , Imunidade Celular , Doenças das Aves Domésticas/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia , Vacinas Vivas não Atenuadas/administração & dosagem , Vacinas Vivas não Atenuadas/imunologia , Vacinas Virais/administração & dosagem
17.
Acta Virol ; 63(1): 19-25, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30879309

RESUMO

Chicken infectious anemia (CIA) is an immunosuppressive disease that causes great economic loss in poultry industry globally. This disease is caused by chicken anemia virus (CAV), an icosahedral and single-stranded DNA virus that is transmitted both vertically and horizontally. CAV, which belongs to the genus Gyrovirus has been reported in human, mouse and dog feces. Rapid identification of different strains of gyrovirus with high similarity to CAV has heightened public concern on this virus. Clinical symptoms of this disease such as intramuscular hemorrhage, weight loss, anemia and bone marrow aplasia are prominent in young chickens, while adult chickens experience subclinical symptoms. Biosecurity measures such as good management practice and vaccination have been the most reliable control strategy against this virus. Therefore, this study reviews the current state of CAV under the following subheadings (i) Chicken anemia virus (ii) Pathogenesis of CAV (iii) Serological evaluation of host antibodies to CAV (iv) Association of Marek's disease and infectious bursa disease with CAV infection (v) Genetic diversity and phylogenetics of CAV strains (vi) Current and future vaccine strategy in the control of CAV. In conclusion, improvement on DNA and recombinant vaccines strategy could curtail the economic impact of CAV on poultry birds. Keywords: adjuvant; CAV; chicken; disease.


Assuntos
Vírus da Anemia da Galinha , Infecções por Circoviridae , Doenças das Aves Domésticas , Animais , Anticorpos Antivirais/sangue , Vírus da Anemia da Galinha/classificação , Vírus da Anemia da Galinha/imunologia , Galinhas , Infecções por Circoviridae/imunologia , Infecções por Circoviridae/veterinária , Infecções por Circoviridae/virologia , Aves Domésticas , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologia , Vacinação/tendências , Vacinação/veterinária , Vacinas Virais/normas
18.
Vet Res ; 50(1): 18, 2019 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-30823888

RESUMO

The G1-H9N2 avian influenza virus (AIV) has caused significant economic losses in the commercial poultry industry due to reduced egg production and increased mortality. The field observations have shown that H9N2 viruses circulate and naturally mix with other pathogens and these simultaneous infections can exacerbate disease. To avoid an incorrect virus characterization, due to co-infection, isolates were purified by in vitro plaque assays. Two plaque purified G1-H9N2 clones, selected on different cell types, named MDCK-and CEF-clone in regards to the cell culture used, were studied in vivo, revealing two different virulence phenotypes. Subsequently, the underlying mechanisms were studied. Specifically, the phenotypical outcome of SPF bird infection by the two clones resulted in completely different clinical outcomes. These differences in clinical outcome were used to study the factors behind this output in more detail. Further studies demonstrated that the more severe disease outcome associated with the MDCK-clone involves a strong induction of pro-inflammatory cytokines and a lack of type I interferon production, whereas the mild disease outcome associated with the CEF-clone is related to a greater antiviral cytokine response. The immunosuppressive effect of the MDCK-clone on splenocytes was further demonstrated via ChIFN-γ lack production after ex vivo mitogenic stimulation. Genome sequencing of the two clones identified only four amino acid differences including three in the HA sequence (HA-E198A, HA-R234L, HA-E502D-H9 numbering) and one in the NA sequence (NA-V33M). In the present study, valuable insights on the mechanisms responsible for AI pathogenicity and molecular mechanisms of H9N2 infections in chicken were obtained while highlighting the impact of the cells viruses are grown on their virulence.


Assuntos
Vírus da Influenza A Subtipo H9N2/patogenicidade , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Animais , Galinhas/imunologia , Galinhas/virologia , Regulação da Expressão Gênica , Genoma Viral/genética , Testes de Inibição da Hemaglutinação/veterinária , Imunidade Inata , Técnicas In Vitro , Vírus da Influenza A Subtipo H9N2/genética , Vírus da Influenza A Subtipo H9N2/isolamento & purificação , Influenza Aviária/imunologia , Influenza Aviária/patologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/patologia , Reação em Cadeia da Polimerase em Tempo Real , Análise de Sequência de DNA/veterinária , Ensaio de Placa Viral/veterinária , Virulência , Eliminação de Partículas Virais
19.
Poult Sci ; 98(8): 3150-3157, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30919905

RESUMO

Immunoglobulins, which are passed vertically from hens to their progeny, are first present in the eggs but with time also in the developing embryos and eventually in the serum of hatching chicks, and have protective function during embryogenesis and in the first few weeks of birds' life, before the immune system becomes fully efficient. Considering the above fact, the aim of this study was to determine total levels of IgM and IgY as well as specific IgY antibody titers against selected pathogens in the serum of breeder turkeys and their progeny, as well as in egg yolks and egg whites. Study results demonstrated that the level of IgY antibodies in the serum of turkey breeder hens reached 22.04 mg/mL on average in the whole egg laying cycle. In addition, the mean transfer percentage of IgY antibodies from turkey layers to their progeny reached approximately 31.4%, but the level of this transfer differed depending on pathogen character and accounted for 33.2%, 51.9%, 45.1%, and 44.3% in the case of antibodies against avian metapneumoviruses, Newcastle disease virus, Ornithobacterium rhinortacheale, and Pasteurella multocida, respectively. Antibody percentage transfer differed also as affected by the stage of the egg production cycle. Study results confirmed the earlier observed dependency concerning the class of antibodies transferred to eggs from laying hens, and while the IgY were mainly detected in the egg yolk extracts, the IgM were found only in egg white extracts; in comparison to IgY, the IgM antibodies were not transferred to the serum of turkey poults. To our best knowledge, this is the first study that describes in detail the phenomenon of maternal antibody transfer in turkeys.


Assuntos
Anticorpos/análise , Imunidade Materno-Adquirida , Óvulo/imunologia , Doenças das Aves Domésticas/imunologia , Animais , Feminino , Imunoglobulina G/sangue , Imunoglobulinas/sangue , Metapneumovirus/imunologia , Vírus da Doença de Newcastle/imunologia , Ornithobacterium/imunologia , Pasteurella multocida/imunologia , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/virologia , Perus/imunologia
20.
Poult Sci ; 98(7): 2800-2812, 2019 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-30877749

RESUMO

The objective of this study was to evaluate performance, diversity, composition, and predicted function of the intestinal microbiota of broilers raised under 3 different methods to induce necrotic enteritis (NE). The chicks in Experiments 1 and 2 were vaccinated against coccidiosis on day 1. Experiment 1: non-challenged and challenged birds were raised in floor pens with new litter and 58 birds/pen. The challenge consisted of Eimeria maxima inoculation on day 14 and Clostridium perfringens via water on days 18 to 19. Cecal microbiota was evaluated on days 18, 21, and 28. Experiment 2: non-challenged and challenged birds were raised in floor pens with recycled litter and 50 birds/pen. The challenge consisted of C. perfringens via feed from days 18 to 20. Ileal and cecal microbiota were evaluated on day 21. In Experiment 3, non-challenged and challenged birds were raised in battery cages with 8 birds/cage. Challenged birds were inoculated with E. maxima on day 14 and with C. perfringens on days 19 to 21. In the 3 experiments, ileal or cecal microbiota or both were analyzed through 16S rRNA sequencing. The performance of the birds was impaired in the 3 studies, regardless of the method used to induce NE. In Experiment 1, the microbiota did not significantly change across ages. In Experiment 2, α-diversity indices were lower in challenged vs. non-challenged birds in both ileal and cecal microbiota. The cecal microbiota composition and function was more affected than the ileal microbiota. In Experiment 3, Chao index (α-diversity) increased in challenged vs. non-challenged birds, and the composition of the ileal and cecal microbiota was not significantly affected. In conclusion, the overall feed conversion ratio was more affected in Experiment 3 (5.2, 11.1, and 30% for Experiments 1, 2, and 3, respectively), which also showed the highest degree of NE lesions. However, the largest variations of diversity and composition of the microbiota were observed in Experiment 2, when birds were raised in floor pens with reused litter, vaccinated against coccidiosis, and challenged with C. perfringens on days 19 to 21.


Assuntos
Enterite/veterinária , Microbioma Gastrointestinal , Necrose/veterinária , Doenças das Aves Domésticas/microbiologia , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Galinhas , Infecções por Clostridium/imunologia , Infecções por Clostridium/prevenção & controle , Infecções por Clostridium/veterinária , Clostridium perfringens/fisiologia , Coccidiose/imunologia , Coccidiose/prevenção & controle , Coccidiose/veterinária , Eimeria/fisiologia , Enterite/microbiologia , Necrose/microbiologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/prevenção & controle , RNA Ribossômico 16S , Vacinação/veterinária
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