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1.
Gene ; 766: 145077, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32941951

RESUMO

Newcastle disease virus (NDV) is a contagious poultry paramyxovirus, leading to substantial economic losses to the poultry industry. Here, RNA-seq was carried out to investigate the altered expression of immune-related genes in chicken thymus within 96 h in response to NDV infection. In NDV-infected chicken thymus tissues, comparative transcriptome analysis revealed 1386 differentially expressed genes (DEGs) at 24 h with 989 up- and 397 down-regulated genes, 728 DEGs at 48 h with 567 up- and 161 down-regulated genes, 1514 DEGs at 72 h with 1016 up- and 498 down-regulated genes, and 1196 DEGs at 96 h with 522 up- and 674 down-regulated genes, respectively. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis showed that these candidate targets mainly participate in biological processes or biochemical, metabolic and signal transduction processes. Notably, there is large enrichment in biological processes, cell components and metabolic processes, which may be related to NDV pathogenicity. In addition, the expression of five immune-related DEGs identified by RNA-seq was validated by quantitative real-time polymerase chain reaction (qRT-PCR). Our results indicated that the expression levels of AvBD5, IL16, IL22 and IL18R1 were obviously up-regulated, and Il-18 expression was also changed, but not significantly, which play key roles in the defense against NDV. Overall, we identified several candidate targets that may be involved in the regulation of NDV infection, which provide new insights into the complicated regulatory mechanisms of virus-host interactions, and explore new strategies for protecting chickens against the virus.


Assuntos
Galinhas/genética , Galinhas/imunologia , Doença de Newcastle/genética , Doença de Newcastle/imunologia , Vírus da Doença de Newcastle/imunologia , Transcriptoma/genética , Vacinas Virais/imunologia , Animais , Galinhas/virologia , Regulação para Baixo/imunologia , Perfilação da Expressão Gênica/métodos , Doença de Newcastle/virologia , Doenças das Aves Domésticas/genética , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologia , Análise de Sequência de RNA/métodos , Transcriptoma/imunologia , Regulação para Cima/imunologia
2.
Arch Virol ; 165(12): 2877-2881, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32885326

RESUMO

Avian leukosis virus (ALV) is associated with immune suppression, neoplasia, and reduced performance in chickens. In this study, two strains of ALV were isolated from Luxi gamecocks by DF-1 cell culture and identified by PCR, immunofluorescence assay, and sequencing of the viral genome. These strains were found to be novel recombinant viruses with nucleotide sequence identity of over 93.0% in the LTR and 94.4% in U3 to ALV-J, over 95.0% in the 5'UTR to ALV-C, over 93.4% in gp85 to ALV-B, and over 96.0% in gp37 to ALV-E. These results indicate that these two isolates are recombinants between ALV-J, ALV-C, ALV-E and ALV-B.


Assuntos
Vírus da Leucose Aviária/isolamento & purificação , Leucose Aviária/virologia , Galinhas/virologia , Genoma Viral , Doenças das Aves Domésticas/virologia , Vírus Reordenados/isolamento & purificação , Animais , Vírus da Leucose Aviária/patogenicidade , Sequência de Bases , China , Filogenia , Vírus Reordenados/patogenicidade , Análise de Sequência , Proteínas do Envelope Viral/genética , Virulência
3.
Arch Virol ; 165(11): 2589-2597, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32876794

RESUMO

Marek's disease (MD) is a contagious avian viral disease that is responsible for large economic losses to farmers. The disease is caused by Marek's disease virus (species Gallid alphaherpesvirus 2), which causes neurological lesions, immune suppression, and tumor proliferation of lymphoid cells that invade a large number of organs and tissues. Despite widespread vaccination, Marek's disease virus (MDV), has shown a continuous increase in its virulence and has acquired the ability to overcome immune responses induced by vaccines. In the present study, the oncogenic serotype MDV-1 was detected by real-time PCR in DNA samples extracted from organs developing tumor infiltrations. Identification of the pathotype based on a 132-bp tandem repeat and sequencing and phylogenetic analysis of the Meq gene and its encoded protein allowed classification of the isolated viruses as "very virulent", with two new and unique mutations in the Meq gene resulting in amino acid substitutions. Sequencing of pp38, vIl-8, UL1 and UL44 genes did not reveal any new mutations that were characteristic of the Tunisian isolates or correlated with virulence. These results raised concerns about the ability of HVT and CVI988 vaccines, which are currently used in Tunisia and other countries, to protect chickens against highly virulent virus strains.


Assuntos
Herpesvirus Galináceo 2/genética , Herpesvirus Galináceo 2/patogenicidade , Proteínas Oncogênicas Virais/genética , Filogenia , Sequência de Aminoácidos , Animais , Galinhas/virologia , DNA Viral/química , Doença de Marek/virologia , Mutação Puntual , Polimorfismo de Fragmento de Restrição , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Tunísia , Virulência/genética
4.
Genes (Basel) ; 11(8)2020 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-32785186

RESUMO

The coronaviruses are a large family of enveloped RNA viruses that commonly cause gastrointestinal or respiratory illnesses in the infected host. Avian coronavirus infectious bronchitis virus (IBV) is a highly contagious respiratory pathogen of chickens that can affect the kidneys and reproductive systems resulting in bird mortality and decreased reproductivity. The interferon-inducible transmembrane (IFITM) proteins are activated in response to viral infections and represent a class of cellular restriction factors that restrict the replication of many viral pathogens. Here, we characterize the relative mRNA expression of the chicken IFITM genes in response to IBV infection, in vivo, ex vivo and in vitro using the pathogenic M41-CK strain, the nephropathogenic QX strain and the nonpathogenic Beaudette strain. In vivo we demonstrate a significant upregulation of chIFITM1, 2, 3 and 5 in M41-CK- and QX-infected trachea two days post-infection. In vitro infection with Beaudette, M41-CK and QX results in a significant upregulation of chIFITM1, 2 and 3 at 24 h post-infection. We confirmed a differential innate response following infection with distinct IBV strains and believe that our data provide new insights into the possible role of chIFITMs in early IBV infection.


Assuntos
Galinhas/genética , Galinhas/virologia , Infecções por Coronavirus/veterinária , Interações Hospedeiro-Patógeno/genética , Proteínas de Membrana/genética , Animais , Infecções por Coronavirus/genética , Regulação Viral da Expressão Gênica , Interações Hospedeiro-Patógeno/fisiologia , Vírus da Bronquite Infecciosa/patogenicidade , Vírus da Bronquite Infecciosa/fisiologia , Técnicas de Cultura de Órgãos , Doenças das Aves Domésticas/etiologia , Doenças das Aves Domésticas/genética , Doenças das Aves Domésticas/virologia , Carga Viral , Tropismo Viral
5.
PLoS One ; 15(8): e0238068, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32841290

RESUMO

Newcastle Disease (ND) is a viral disease spread worldwide with a high impact on economy and animal welfare. Vaccination against Newcastle Disease is one of the main control measures in countries such as Germany with endemic occurrence of Newcastle Disease virus in the free ranging bird population. The German Standing Veterinary Committee on Immunization (StIKo Vet) recommends to revaccinate chickens at intervals of six weeks against Newcastle Disease with attenuated live vaccines via drinking water or spray in line with the SPCs (Summary of Product Characteristics) of current vaccines. However, it is still common practice to revaccinate only every twelve weeks because the SPCs of former vaccines proposed a revaccination after checking the antibody titer which based on practical knowledge was typically sufficient for twelve weeks. The aim of this study was to evaluate if a vaccination interval of twelve weeks against Newcastle Disease under field conditions results in sufficient seroconversion to protect flocks. Antibody titers of 810 blood samples from 27 backyard flocks of chickens were analyzed by ELISA- and HI-tests between 69 and 111 days after vaccination of the flocks with attenuated live vaccines of the ND strain Clone 30. Furthermore, data on the flocks such as breed, sex and age were collected through a questionnaire. In this study a sufficient antibody titer was found in 26 of these flocks. Therefore, a vaccination interval of every twelve weeks with the live vaccines tested is suitable for a vaccination protocol against Newcastle Disease. The lack of seroconversion of one flock also emphasizes the need for regular vaccination monitoring by serological testing and re-evaluation of the vaccination process if needed.


Assuntos
Anticorpos Antivirais/análise , Galinhas/imunologia , Galinhas/virologia , Doença de Newcastle/prevenção & controle , Vacinação/métodos , Animais , Alemanha , Fatores de Tempo
6.
Methods Mol Biol ; 2203: 1-29, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32833200

RESUMO

Coronaviruses (CoVs), enveloped positive-sense RNA viruses, are characterized by club-like spikes that project from their surface, an unusually large RNA genome, and a unique replication strategy. CoVs cause a variety of diseases in mammals and birds ranging from enteritis in cows and pigs, and upper respiratory tract and kidney disease in chickens to lethal human respiratory infections. Most recently, the novel coronavirus, SARS-CoV-2, which was first identified in Wuhan, China in December 2019, is the cause of a catastrophic pandemic, COVID-19, with more than 8 million infections diagnosed worldwide by mid-June 2020. Here we provide a brief introduction to CoVs discussing their replication, pathogenicity, and current prevention and treatment strategies. We will also discuss the outbreaks of the highly pathogenic Severe Acute Respiratory Syndrome Coronavirus (SARS-CoV) and Middle Eastern Respiratory Syndrome Coronavirus (MERS-CoV), which are relevant for understanding COVID-19.


Assuntos
Doenças dos Animais/virologia , Betacoronavirus/fisiologia , Galinhas/virologia , Infecções por Coronavirus/virologia , Coronavirus/fisiologia , Pneumonia Viral/virologia , Síndrome Respiratória Aguda Grave/virologia , Doenças dos Animais/diagnóstico , Doenças dos Animais/epidemiologia , Doenças dos Animais/prevenção & controle , Animais , Betacoronavirus/genética , Betacoronavirus/patogenicidade , Bovinos , Coronavirus/genética , Coronavirus/patogenicidade , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/prevenção & controle , Humanos , Coronavírus da Síndrome Respiratória do Oriente Médio/genética , Coronavírus da Síndrome Respiratória do Oriente Médio/patogenicidade , Coronavírus da Síndrome Respiratória do Oriente Médio/fisiologia , Pandemias/prevenção & controle , Pneumonia Viral/diagnóstico , Pneumonia Viral/epidemiologia , Pneumonia Viral/prevenção & controle , Vírus da SARS/genética , Vírus da SARS/patogenicidade , Vírus da SARS/fisiologia , Síndrome Respiratória Aguda Grave/diagnóstico , Síndrome Respiratória Aguda Grave/epidemiologia , Síndrome Respiratória Aguda Grave/prevenção & controle , Glicoproteína da Espícula de Coronavírus/genética , Suínos , Vírion , Replicação Viral
7.
Euro Surveill ; 25(25)2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32613937

RESUMO

The advent of COVID-19, has posed a risk that human respiratory samples containing human influenza viruses may also contain SARS-CoV-2. This potential risk may lead to SARS-CoV-2 contaminating conventional influenza vaccine production platforms as respiratory samples are used to directly inoculate embryonated hen's eggs and continuous cell lines that are used to isolate and produce influenza vaccines. We investigated the ability of these substrates to propagate SARS-CoV-2 and found that neither could support SARS-CoV-2 replication.


Assuntos
Galinhas/imunologia , Coronavirus/fisiologia , Vacinas contra Influenza/imunologia , Influenza Humana/prevenção & controle , Células Madin Darby de Rim Canino , Receptores Virais/metabolismo , Cultura de Vírus/métodos , Replicação Viral , Animais , Betacoronavirus , Linhagem Celular , Galinhas/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Cães , Ovos , Humanos , Pandemias , Pneumonia Viral , Síndrome Respiratória Aguda Grave
8.
Arch Virol ; 165(10): 2249-2258, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32696270

RESUMO

While infectious bursal disease virus (IBDV) mainly targets immature B cells and causes T cell infiltration in the bursa of Fabricius (BF) of chickens, the effect of IBDV infection on the properties of T cells and relevant cytokine production in avian gut-associated lymphoid tissues (GALTs) remains unknown. Here, we show that while the CD8+ T cell subset is not affected, IBDV infection decreases the percentage of CD4+ T cells in the cecal tonsil (CT), but not in esophagus tonsil, pylorus tonsil, and Meckel's diverticulum of GALTs, in contrast to BF and spleen, in which the proportion of CD4+ cells increases upon IBDV infection. Further, IBDV infection upregulates IFN-γ, IL-10, and the T cell checkpoint receptor LAG-3 mRNA expression in BF. In contrast, in CTs, IBDV infection significantly increases the production of IFN-ß and CTLA-4 mRNA, while no significant effect is seen in the case of IFN-γ, IL-10 and LAG-3. Together, our data reveal differential modulation of T cell subsets and proinflammatory cytokine production in different lymphoid tissues during the course of IBDV infection.


Assuntos
Subpopulações de Linfócitos B/imunologia , Infecções por Birnaviridae/imunologia , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD8-Positivos/imunologia , Regulação da Expressão Gênica/imunologia , Doenças das Aves Domésticas/imunologia , Animais , Antígenos CD/genética , Antígenos CD/imunologia , Subpopulações de Linfócitos B/virologia , Infecções por Birnaviridae/genética , Infecções por Birnaviridae/patologia , Infecções por Birnaviridae/virologia , Bolsa de Fabricius/imunologia , Bolsa de Fabricius/virologia , Linfócitos T CD4-Positivos/virologia , Linfócitos T CD8-Positivos/virologia , Antígeno CTLA-4/genética , Antígeno CTLA-4/imunologia , Galinhas/virologia , Vírus da Doença Infecciosa da Bursa/crescimento & desenvolvimento , Vírus da Doença Infecciosa da Bursa/imunologia , Vírus da Doença Infecciosa da Bursa/patogenicidade , Interferon beta/genética , Interferon beta/imunologia , Interferon gama/genética , Interferon gama/imunologia , Interleucina-10/genética , Interleucina-10/imunologia , Mucosa Intestinal/imunologia , Mucosa Intestinal/virologia , Tonsila Palatina/imunologia , Tonsila Palatina/virologia , Doenças das Aves Domésticas/genética , Doenças das Aves Domésticas/patologia , Doenças das Aves Domésticas/virologia
9.
Arch Razi Inst ; 75(2): 155-162, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32621443

RESUMO

Coronaviruses (AvCoV) which include infectious bronchitis virus (IBV) and other bird coronaviruses belong to the genus gammacoronavirus, subfamily Coronavirinae. One of the most prominent representatives of gammacoronavirus genus is infectious bronchitis virus (IBV) which is a highly contagious viral pathogen of chickens causing considerable economic losses to the poultry industry. IBVs mostly affect the respiratory, urinary, and reproductive tracts leading to a substantial drop in production. Backyard poultry in the villages usually share their food and water with free flight birds which puts them at serious risk of disease transmission. Furthermore, the poor hygienic measurements which are often used in backyard flocks make them a potential reservoir for diseases that can be transferred to commercial poultry flocks. Live bird markets (LBMs) which receive live poultry to be resold or slaughtered and sold onsite play a significant role in spreading infectious diseases among the different bird species. In the present study, a number of 354 cloacal swab samples were collected from different bird species from LBMs of Gilan province. Subsequently, after RNA extraction, reverse transcription-polymerase chain reaction (RT-PCR) technique was carried out using specific primers of S1 gene to detect coronavirus infectious bronchitis virus. Two samples from backyard chickens were reported to be positive to coronavirus which were named Iran/Backyardchicken 96/2017 and Iran/Backyardchicken 94/2017. The results of the phylogenetic analysis demonstrated that these two isolates are placed in QX and IS-1494 strains, respectively. On a final note, the obtained results highlighted the role of live birds offered in LBMs in the epidemiology of IBV and the transmission of the virus to the industrial flock.


Assuntos
Galinhas/virologia , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa , Doenças das Aves Domésticas/virologia , Animais , Cloaca/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Vírus da Bronquite Infecciosa/genética , Irã (Geográfico)/epidemiologia , Filogenia , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/epidemiologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa/veterinária , Análise de Sequência de DNA/veterinária
10.
Vet Res Commun ; 44(3-4): 101-110, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32651761

RESUMO

The outbreak of the SARS-CoV-2 in mainland China with subsequent human to human transmission worldwide had taken up the shape of a devastating pandemic. The ability of the virus to infect multiple species other than humans has currently been reported in experimental conditions. Non-human primates, felines, ferrets, rodents and host of other animals could previously be infected in experimental conditions with SARS-CoV and recently with SARS-CoV-2, both virus using Angiotensin-converting-enzyme 2 receptor for cellular entry. The variations in sequence homology of ACE2 receptor across species is identified as one of the factors determining virulence and pathogenicity in animals. The infection in experimental animals with SARS-CoV or SARS-CoV-2 on most occasions are asymptomatic, however, the virus could multiply within the respiratory tract and extra-pulmonary organs in most of the species. Here, we discuss about the pathogenicity, transmission, variations in angiotensin-converting-enzyme 2 receptor-binding across species and host pathogen interactions of SARS and SARS-CoV-2 in laboratory animals used in research.


Assuntos
Betacoronavirus/patogenicidade , Infecções por Coronavirus/veterinária , Interações Hospedeiro-Patógeno , Pandemias/veterinária , Pneumonia Viral/veterinária , Vírus da SARS/patogenicidade , Síndrome Respiratória Aguda Grave/veterinária , Animais , Callithrix/virologia , Gatos/virologia , Galinhas/virologia , Quirópteros/virologia , Chlorocebus aethiops/virologia , Infecções por Coronavirus/transmissão , Infecções por Coronavirus/virologia , Cricetinae/virologia , Furões/virologia , Macaca fascicularis/virologia , Macaca mulatta/virologia , Camundongos , Camundongos Endogâmicos/virologia , Pneumonia Viral/transmissão , Pneumonia Viral/virologia , Roedores/virologia , Síndrome Respiratória Aguda Grave/transmissão , Síndrome Respiratória Aguda Grave/virologia , Suínos/virologia
11.
Genes (Basel) ; 11(6)2020 05 29.
Artigo em Inglês | MEDLINE | ID: mdl-32486006

RESUMO

In the last 5 years, frequent outbreaks of infectious bronchitis virus (IBV) are observed in both broiler and layer chicken flocks in the Kingdom of Saudi Arabia (KSA) in spite of extensive usage of vaccines. The IBV is a widespread avian coronavirus affecting both vaccinated and unvaccinated chicken flocks and is attributed to significant economic losses, around the globe. In the present study, 58 (n = 58) samples were collected from four different commercial poultry flocks from 8 KSA districts during 2019. A total of nine positive isolates (9/58; 15.5%), based on real-time reverse transcriptase PCR targeting nucleocapsid (N) gene, were used for further genetic characterization and evolutionary analysis. Genetic characterization of the partial spike (S1) gene revealed the clustering of the reported isolates into three different genotypes, whereas four additional isolates were grouped within 4/91 genotype, two isolates within IS/885 genotype, one isolate was closely related to IS/1494/06, and two isolates were grouped within classic serotype (vaccine-like strains). Phylodynamic revealed clustering of four isolated viruses within GI-13 lineage, three isolates within GI-23 lineage, and two isolates within GI-1 lineage. Results indicate that there are high evolutionary distances between the newly identified IBV strains in this study and the commercially used vaccines (GI-1), suggesting that IBV strains circulating in the KSA are under constant evolutionary pressures. Selective pressure biostatistics analyses consistently demonstrate the presence of a higher positive score which highlights the role of natural selection, a mechanism of virus evolution on sites located on the protein surface, within or nearby domains involved in viral attachment or related functions. Recombination analysis revealed emergence of two isolates through recombination events resulting in new recombinant viruses. Taken together, these finding demonstrate the genetic and evolutionary insights into the currently circulating IBV genotypes in KSA, which could help to better understand the origin, spread, and evolution of infectious bronchitis viruses, and to ascertain the importance of disease monitoring as well as re-evaluation for the currently used vaccines and vaccination programs.


Assuntos
Variação Genética , Vírus da Bronquite Infecciosa/genética , Doenças das Aves Domésticas/virologia , Recombinação Genética , Aminoácidos/genética , Animais , Galinhas/virologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Evolução Molecular , Vírus da Bronquite Infecciosa/isolamento & purificação , Epidemiologia Molecular , Filogenia , Doenças das Aves Domésticas/epidemiologia , Arábia Saudita/epidemiologia , Seleção Genética , Proteínas Virais/genética , Proteínas Virais/metabolismo , Vacinas Virais/uso terapêutico
12.
Genet Sel Evol ; 52(1): 29, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-32487054

RESUMO

BACKGROUND: Avian leukosis virus subgroup E (ALVE) insertions are endogenous retroviruses (ERV) that are restricted to the domestic chicken and its wild progenitor. In commercial chickens, ALVE are known to have a detrimental effect on productivity and provide a source for recombination with exogenous retroviruses. The wider diversity of ALVE in non-commercial chickens and the role of these elements in ERV-derived immunity (EDI) are yet to be investigated. RESULTS: In total, 974 different ALVE were identified from 407 chickens sampled from village populations in Ethiopia, Iraq, and Nigeria, using the recently developed obsERVer bioinformatics identification pipeline. Eighty-eight percent of all identified ALVE were novel, bringing the known number of ALVE integrations to more than 1300 across all analysed chickens. ALVE content was highly lineage-specific and populations generally exhibited a large diversity of ALVE at low frequencies, which is typical for ERV involved in EDI. A significantly larger number of ALVE was found within or near coding regions than expected by chance, although a relative depletion of ALVE was observed within coding regions, which likely reflects selection against deleterious integrations. These effects were less pronounced than in previous analyses of chickens from commercial lines. CONCLUSIONS: Identification of more than 850 novel ALVE has trebled the known diversity of these retroviral elements. This work provides the basis for future studies to fully quantify the role of ALVE in immunity against exogenous ALV, and development of programmes to improve the productivity and welfare of chickens in developing economies.


Assuntos
Vírus da Leucose Aviária/genética , Animais , Animais Selvagens , Galinhas/virologia , Retrovirus Endógenos/genética , Etiópia , Variação Genética/genética , Iraque , Nigéria
13.
Virus Res ; 285: 198002, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32380209

RESUMO

In the present study, an IBV strain I0305/19 was isolated from a diseased commercial broiler flock in 2019 in China with high morbidity and mortality. The isolate I0305/19 was clustered together with viruses in sublineage D of GI-19 lineage on the basis of the complete S1 sequence analysis. Isolate I0305/19 and other GI-19 viruses isolated in China have the amino acid sequence MIA at positions 110-112 in the S protein. Further analysis based on the complete genomic sequence showed that the isolate emerged through at least four recombination events between GI-19 ck/CH/LJS/120848- and GI-13 4/91-like strains, in which the S gene was found to be similar to that of the GI-19 ck/CH/LJS/120848-like strain. Pathological assessment showed the isolate was a nephropathogenic IBV strain that caused high morbidity of 100 % and mortality of 80 % in 1-day-old specific-pathogen-free (SPF) chicks. The isolate I0305/19 exhibited broader tropisms in different tissues, including tracheas, lungs, bursa of Fabricius, spleen, liver, kidneys, proventriculus, small intestines, large intestines, cecum, and cecal tonsils. Furthermore, subpopulations of the virus were found in tissues of infected chickens; this finding is important in understanding how the virulent IBV strains can potentially replicate and evolve to cause disease. This information is also valuable for understanding the mechanisms of replication and evolution of other coronaviruses such as the newly emerged SARS-CoV-2.


Assuntos
Galinhas/virologia , Infecções por Coronavirus/veterinária , Vírus da Bronquite Infecciosa/genética , Vírus da Bronquite Infecciosa/patogenicidade , Doenças das Aves Domésticas/virologia , Recombinação Genética , Tropismo Viral , Animais , China , Infecções por Coronavirus/virologia , Genoma Viral , Vírus da Bronquite Infecciosa/classificação , Vírus da Bronquite Infecciosa/fisiologia , Filogenia , Organismos Livres de Patógenos Específicos , Glicoproteína da Espícula de Coronavírus/genética , Replicação Viral
14.
PLoS One ; 15(5): e0232571, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32442180

RESUMO

Molecular-based testing of poultry dust has been used as a fast, sensitive and specific way to monitor viruses in chicken flocks but it provides no information on viral viability. Differentiation of viable and nonviable virus would expand the usefulness of PCR-based detection. This study tested three treatments (1. DNAse, 2. propidium monoazide [PMA], 3. immunomagnetic separation [IMS]) applied to dust or virus stock prior to nucleic acid extraction for their ability to exclude nonviable virus from PCR amplification. Infectious laryngotracheitis virus (ILTV) was used as a model. These treatments assume loss of viral viability due to damage to the capsid or to denaturation of epitope proteins. DNAse and PMA assess the integrity of the capsid to penetration by enzyme or intercalating dye, while IMS assesses the integrity of epitope proteins. Treatments were evaluated for their ability to reduce PCR signal, measured as ILTV log10 genomic copies (ILTV GC), of heat and chemically inactivated ILTV in poultry dust and virus stock. Compared to untreated dust samples, there was an overall reduction of 1.7 ILTV GC after IMS treatment (p<0.01), and a reduction of 2.0 ILTV GC after PMA treatment (p<0.0001). DNAse treatment did not reduce ILTV GC in dust (p = 0.68). Compared to untreated virus stocks, there was an overall reduction of 0.5 ILTV GC after DNAse treatment (p = 0.04), a reduction of 1.8 ILTV GC after IMS treatment (p<0.001) and a reduction of 1.4 ILTV GC after PMA treatment (p<0.0001). None of the treatments completely suppressed the detection of inactivated ILTV GC. In conclusion, treatments that use capsid integrity or protein epitope denaturation as markers to assess ILTV infectivity are unsuitable to accurately estimate proportions of viable virus in poultry dust and virus stocks.


Assuntos
DNA Viral/genética , Infecções por Herpesviridae/veterinária , Herpesvirus Galináceo 1/genética , Doenças das Aves Domésticas/virologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Animais , Embrião de Galinha/virologia , Galinhas/virologia , Infecções por Herpesviridae/diagnóstico , Infecções por Herpesviridae/virologia , Separação Imunomagnética/veterinária , Doenças das Aves Domésticas/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real/métodos
15.
J Gen Virol ; 101(6): 645-650, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32391749

RESUMO

Lumpy skin disease virus (LSDV), a Capripoxvirus, is of economic importance in the cattle industry and is controlled by vaccination. A comparison was made of the host response to the two LSDV vaccines Neethling and Herbivac LS, with reference to the well-studied Orthopoxvirus, modified vaccinia Ankara (MVA), in a mouse model. Because the vaccines differ at the superoxide dismutase homologue (SOD) gene locus, recombinant SOD knock-out and knock-in nLSDV vaccines were constructed and all four vaccines were tested for the induction and inhibition of apoptosis. The SOD homologue was associated both with induction of apoptosis as well as inhibition of camptothecin-induced apoptosis. Histological analysis of chorioallantoic membranes of fertilized hens' eggs infected with the four different vaccines indicated marked mesodermal proliferation associated with vaccines containing the full-length SOD homologue as well as increased immune cell infiltration. Our findings suggest that the SOD homologue may influence vaccine immunogenicity.


Assuntos
Apoptose/genética , Interações Hospedeiro-Patógeno/genética , Doença Nodular Cutânea/genética , Doença Nodular Cutânea/virologia , Vírus da Doença Nodular Cutânea/genética , Superóxido Dismutase/genética , Transcrição Genética/genética , Animais , Apoptose/imunologia , Bovinos , Galinhas/imunologia , Galinhas/virologia , Feminino , Doença Nodular Cutânea/imunologia , Vírus da Doença Nodular Cutânea/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Superóxido Dismutase/imunologia , Transcrição Genética/imunologia , Vacinação/métodos , Vacinas Atenuadas/imunologia , Vírus Vaccinia/genética , Vírus Vaccinia/imunologia , Vacinas Virais/imunologia
16.
Arch Virol ; 165(6): 1367-1375, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32285201

RESUMO

Sequencing of the VP2 region was carried out to identify amino acid mismatches between vaccine strains and field isolates of infectious bursal disease virus (IBDV). Viruses were isolated in chicken embryo fibroblast (DF-1) cells using pooled samples of bursa collected from nine outbreaks, which affected 30,250 chickens in five localities, with an overall mortality of 47.87%. Virus strains were identified by comparing the deduced amino acid sequence between positions 232 and 446 of the immunodominant VP2 epitope. All of the pooled samples were positive for IBDV. RT-PCR yielded a 645-bp DNA fragment of the VP2 gene. Phylogenetic analysis of this fragment revealed clustering of these isolates with very virulent IBDV strains. The amino acid sequences of these isolates were identical to those of the European very virulent strains UK 661 and DV 86, except at position 222, but differed from the vaccine strains used in Ethiopia, suggesting the possible introduction of virulent virus strains to Ethiopia from Europe. Our study demonstrates the widespread presence of very virulent strains of IBDV on poultry farms in Ethiopia and demonstrates the need to evaluate the protective level of existing vaccines against circulating field viruses.


Assuntos
Infecções por Birnaviridae/veterinária , Galinhas/virologia , Doenças das Aves Domésticas/virologia , Proteínas Estruturais Virais/genética , Vacinas Virais/imunologia , Sequência de Aminoácidos , Animais , Infecções por Birnaviridae/virologia , Primers do DNA , Surtos de Doenças/veterinária , Etiópia , Vírus da Doença Infecciosa da Bursa/genética , Filogenia , RNA Viral/genética , Análise de Sequência de RNA/veterinária , Virulência
17.
J Vet Diagn Invest ; 32(3): 444-449, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32270752

RESUMO

An outbreak of inclusion body hepatitis caused by fowl adenovirus serotype 8 (FAdV-8) has caused significant economic losses in the poultry industry worldwide. However, a rapid serology test kit specific to FAdV-8 is not available to date. We developed a fiber-based ELISA using the purified GST-fiber of FAdV-8 as coating antigen to measure antibodies against FAdV-8. Specificity analysis showed that our ELISA could react with sera against FAdV-7, -8a, and -8b, but not with sera against the other pathogens tested. Moreover, detection of positive sera with our ELISA had 83% and 94% agreement with an indirect immunofluorescence assay (IFA) and a commercial ELISA from BioChek, respectively. Our ELISA was also effective in the detection of antibodies against FAdV-8 in sera from both experimentally infected and clinically vaccinated chickens. Our FAdV-8 fiber-based ELISA can be a valuable tool to specifically and sensitively detect antibodies against FAdV-7 and/or -8 in infected or vaccinated chickens.


Assuntos
Anticorpos Antivirais/sangue , Aviadenovirus/imunologia , Galinhas/virologia , Ensaio de Imunoadsorção Enzimática/veterinária , Doenças das Aves Domésticas/virologia , Infecções por Adenoviridae/veterinária , Animais , Aviadenovirus/classificação , Doenças das Aves Domésticas/diagnóstico , Sensibilidade e Especificidade , Sorogrupo , Testes Sorológicos/veterinária
18.
Food Microbiol ; 90: 103486, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32336365

RESUMO

The application of Campylobacter specific bacteriophages appears as a promising food safety tool for the biocontrol of this pathogen in the poultry meat production chain. However, their isolation is a complicated challenge since their occurrence appears to be low. This work assessed the efficiency of seven protocols for recovering Campylobacter phages from chicken skin samples inoculated at phage loads from 5.0 × 101 to 5.0 × 106 PFU/g. The enrichment of chicken skin in selective Bolton broth containing target isolates was the most efficient procedure, showing a low detection limit of 5.0 × 101 PFU/g and high recovery rates of up to 560%. This method's effectiveness increased as phage concentration decreased, showing its suitability for phage isolation. When this method was applied to isolate new Campylobacter phages from retail chicken skin, a total of 280 phages were recovered achieving an isolation success rate of 257%. From the 109 samples 68 resulted phage positive (62%). Chicken skin could be, therefore, considered a rich source in Campylobacter phages. This method is a simple, reproducible and efficient approach for the successful isolation of both group II and III Campylobacter specific bacteriophages, which could be helpful for the enhancement of food safety by reducing this pathogen contamination in broiler meat.


Assuntos
Bacteriófagos/isolamento & purificação , Infecções por Campylobacter/veterinária , Campylobacter/virologia , Galinhas/virologia , Pele/virologia , Virologia/métodos , Animais , Infecções por Campylobacter/microbiologia , Galinhas/microbiologia , Microbiologia de Alimentos/métodos , Inocuidade dos Alimentos/métodos , Produtos Avícolas/microbiologia , Produtos Avícolas/virologia , Pele/microbiologia
19.
Vet Microbiol ; 242: 108577, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32122587

RESUMO

Since 2016, severe outbreaks of hepatic rupture hemorrhage syndrome (HRHS) associated with infections of tentative novel avian hepatitis E virus (HEV) have emerged in chickens in China, causing increased mortality and decreased laying rate in adult hens and disturbing the hatching and breeding of chicks. To further identify the genotype and gain a better understanding of the genetic properties of the avian HEV responsible for that, a strain from Hebei province was isolated, purified and sequenced in this study. Results identified a novel avian HEV genotype, sharing 79.5-86.9% identities with other published avian HEV strains, and having higher identities with Orthohepevirus A HEV strains. More importantly, the new isolate contains various amino-acid substitutions in its functional proteins, including methyltransferase, helicase, RNA-dependent RNA polymerase. The data presented in this report will enhance the current understanding of the genetic diversity of the avian HEV and provide additional insight into the critical factors that determine the pathogenicity.


Assuntos
Genoma Viral , Hemorragia/veterinária , Hepatite Viral Animal/virologia , Hepevirus/genética , Animais , Galinhas/virologia , China , Fazendas , Variação Genética , Genótipo , Hemorragia/virologia , Hepatite Viral Animal/complicações , Hepevirus/patogenicidade , Fígado/patologia , Fígado/virologia , Mutação , Filogenia , Doenças das Aves Domésticas/virologia , Análise de Sequência de DNA , Sequenciamento Completo do Genoma
20.
Vet Microbiol ; 242: 108579, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32122588

RESUMO

In China, variants of infectious bronchitis virus (IBV) evolve continually and diverse recombinant strains have been reported. Here, an IBV strain, designated as ck/CH/LJX/2017/07 (referred as JX17) was isolated from chicken vaccinated with H120 and 4/91 in Jiangxi, China, in 2017. Sequence analysis reveals of the S1 gene of JX17 the highest nucleotide identity of 98.15% with that of GI-7 genotype TW2575/98 strain. Furthermore, whole genome analysis among JX17 and other 18 IBV strains demonstrates that JX17 has the highest nucleotide identity of 95.94% with GI-19 genotype YX10 strain. Among all genes of JX17 except the S1 gene, the N gene and 3' UTR have the highest identity to GI-13 genotype 4/91 strain and the rest genes are the most identical to GI-19 genotype YX10 strain. Analyzed by the RDP and SimPlot, the recombination of JX17 strain was shown to occur in regions which include 5'-terminal S1 gene (20,344 to 22,447 nt), most N gene and 3' UTR (26,163 to 27,648 nt). The pathogenicity study shows that JX17 is a natural low virulent IBV variant which caused respiratory symptoms but no death. Taken together, these results indicate that IBV strains continue to evolve through genetic recombination and three prevalent genotypes in China including QX, TW and 4/91 have started to recombine.


Assuntos
Infecções por Coronavirus/veterinária , Genoma Viral , Vírus da Bronquite Infecciosa/genética , Vírus da Bronquite Infecciosa/patogenicidade , Vírus Reordenados/genética , Recombinação Genética , Animais , Galinhas/virologia , China , Infecções por Coronavirus/virologia , Evolução Molecular , Genótipo , Sequenciamento de Nucleotídeos em Larga Escala , Vírus da Bronquite Infecciosa/classificação , Filogenia , Doenças das Aves Domésticas/virologia , RNA Viral/genética , Vírus Reordenados/patogenicidade , Sequenciamento Completo do Genoma
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