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1.
BMC Vet Res ; 20(1): 41, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38302973

RESUMO

The coinfection of ALVs (ALV-J plus ALV-A or/and ALV-B) has played an important role in the incidence of tumors recently found in China in local breeds of yellow chickens. The study aims to obtain a better knowledge of the function and relevance of ALV coinfection in the clinical disease of avian leukosis, as well as its unique effect on the pathogenicity in Three-yellow chickens. One-day-old Three-yellow chicks (one day old) were infected with ALV-A, ALV-B, and ALV-J mono-infections, as well as ALV-A + J, ALV-B + J, and ALV-A + B + J coinfections, via intraperitoneal injection, and the chicks were then grown in isolators until they were 15 weeks old. The parameters, including the suppression of body weight gain, immune organ weight, viremia, histopathological changes and tumor incidence, were observed and compared with those of the uninfected control birds. The results demonstrated that coinfection with ALVs could induce more serious suppression of body weight gain (P < 0.05), damage to immune organs (P < 0.05) and higher tumor incidences than monoinfection, with triple infection producing the highest pathogenicity. The emergence of visible tumors and viremia occurred faster in the coinfected birds than in the monoinfected birds. These findings demonstrated that ALV coinfection resulted in considerably severe pathogenic and immunosuppressive consequences.


Assuntos
Vírus da Leucose Aviária , Leucose Aviária , Coinfecção , Neoplasias , Doenças das Aves Domésticas , Animais , Galinhas , Coinfecção/veterinária , Virulência , Viremia/veterinária , Leucose Aviária/epidemiologia , Neoplasias/veterinária , Peso Corporal , Doenças das Aves Domésticas/epidemiologia
2.
Front Cell Infect Microbiol ; 13: 1087210, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37009511

RESUMO

Haemonchus contortus is an important parasite that causes disease that seriously endangers ruminant animals cattle, sheep, goat, and camel. Here, we compared the proeomics analysis of three adult Haemonchus contortus isolates from mouflons (Ovis ammon). A total of 1,299 adult worm proteins were identified, and 461 proteins were quantified, of which 82 (108), 83 (97), and 97 (86) significantly upregulated (downregulated) differentially expressed proteins (DEPs) were detected among pairwise comparisons (1-vs.-3, 2-vs.-3, and 2-vs.-1). Liquid chromatography-tandem mass spectrometry (LC-MS/MS) and bioinformatic analysis indicated that these DEPs are mainly concentrated in cellular composition, molecular function, biological function, and catabolism pathways. In addition, Gene Ontology (GO) classification and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses were carried out to screen the DEPs. The main biological processes involved were nucleotide, nucleotide phosphate, ribonucleotide, purine-containing compound, purine ribonucleotide, single-organism, oxoacid, organic, carboxylic, oxoacid metabolic processes and single-organism catabolic processes. The majority of KEGG pathways were found to be related to metabolic pathways, biosynthesis of secondary metabolites, biosynthesis of antibiotics, carbon metabolism, and microbial metabolism in diverse environments. Moreover, we also found differences in the expression of some important or novel regulatory proteases, such as serine hydroxymethyl transferase (SHMT), dihydrolipoyl dehydrogenase (DLD), and transket pyr domain-containing protein (TKPD). In summary, label-free proteomic analysis of adult H. contortus worms displayed significant differences in three different individual isolates, which helps to improve our understanding of the growth and metabolic mechanisms of H. contortus in different individuals and relative natural environments and provides novel drug targets for the treatment of parasitic diseases.


Assuntos
Haemonchus , Proteômica , Bovinos , Ovinos , Animais , Haemonchus/genética , Haemonchus/metabolismo , Cromatografia Líquida , Espectrometria de Massas em Tandem , Proteínas de Helminto/genética , Proteínas de Helminto/metabolismo , Cabras/metabolismo
3.
Arch Virol ; 167(12): 2613-2621, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36070017

RESUMO

Infection with recombinant avian leukosis virus (ALV) has previously been linked to malignancies and immunosuppression. However, the processes behind the unique pathophysiology of recombinant ALV are poorly understood. In this study, we analyzed gene expression patterns in chicken fibroblast cells (CEFs) infected with the recombinant ALV isolate GX14FF03 and used the RNA-seq technique to perform a complete analysis of the transcribed mRNAs. A total of 907 significant differentially expressed genes (SDEGs) were identified. Among these SDEGs, the most significantly upregulated gene was interleukin 8-like 1 (IL8L1), while the most significantly downregulated gene was fibroblast growth factor 16 (FGF16). The 907 SDGEs were highly enriched (p < 0.05) for 252 Gene Ontology (GO) terms, including 197 BP, 3 CC, and 52 MF. According to KEGG data analysis, SDEGs are implicated in eight significant pathways (p < 0.05). Furthermore, protein-protein interaction (PPI) network analysis revealed that IL8L1 interacts with 17 genes. These findings shed light on the molecular mechanisms involved in recombinant ALV infection by showing the mRNA expression profile in CEFs infected with GX14FF03 virus.


Assuntos
Vírus da Leucose Aviária , Leucose Aviária , Doenças das Aves Domésticas , Animais , Embrião de Galinha , Vírus da Leucose Aviária/genética , Galinhas , Fibroblastos/metabolismo
4.
J Virol ; 96(17): e0071722, 2022 09 14.
Artigo em Inglês | MEDLINE | ID: mdl-35950858

RESUMO

The geographical spread and inter-host transmission of the subgroup J avian leukosis virus (ALV-J) may be the most important issues for epidemiology. An integrated analysis, including phylogenetic trees, homology modeling, evolutionary dynamics, selection analysis and viral transmission, based on the gp85 gene sequences of the 665 worldwide ALV-J isolates during 1988-2020, was performed. A new Clade 3 has been emerging and was evolved from the dominating Clade 1.3 of the Chinese Yellow-chicken, and the loss of a α-helix or ß-sheet of the gp85 protein monomer was found by the homology modeling. The rapid evolution found in Clades 1.3 and 3 may be closely associated with the adaption and endemicity of viruses to the Yellow-chickens. The early U.S. strains from Clade 1.1 acted as an important source for the global spread of ALV-J and the earliest introduction into China was closely associated with the imported chicken breeders in the 1990s. The dominant outward migrations of Clades 1.1 and 1.2, respectively, from the Chinese northern White-chickens and layers to the Chinese southern Yellow-chickens, and the dominating migration of Clade 1.3 from the Chinese southern Yellow-chickens to other regions and hosts, indicated that the long-distance movement of these viruses between regions in China was associated with the live chicken trade. Furthermore, Yellow-chickens have been facing the risk of infections of the emerging Clades 2 and 3. Our findings provide new insights for the epidemiology and help to understand the critical factors involved in ALV-J dissemination. IMPORTANCE Although the general epidemiology of ALV-J is well studied, the ongoing evolutionary and transmission dynamics of the virus remain poorly investigated. The phylogenetic differences and relationship of the clades and subclades were characterized, and the epidemics and factors driving the geographical spread and inter-host transmission of different ALV-J clades were explored for the first time. The results indicated that the earliest ALV-J (Clade 1.1) from the United States, acted as the source for global spreads, and Clades 1.2, 1.3 and 3 were all subsequently evolved. Also the epidemiological investigation showed that the early imported breeders and the inter-region movements of live chickens facilitated the ALV-J dispersal throughout China and highlighted the needs to implement more effective containment measures.


Assuntos
Vírus da Leucose Aviária , Leucose Aviária , Galinhas , Filogenia , Doenças das Aves Domésticas , Animais , Leucose Aviária/epidemiologia , Leucose Aviária/transmissão , Vírus da Leucose Aviária/genética , Galinhas/virologia , China , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/virologia , Estados Unidos
6.
Poult Sci ; 100(8): 101099, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34174570

RESUMO

The reticuloendotheliosis virus (REV) and the Marek's disease virus (MDV) cause reticuloendotheliosis (RE) and Marek's disease (MD) in poultry, respectively. According to epidemiological results obtained in our laboratory from 2010 to 2017, the positive rates of REV and MDV co-infection remained at low levels. In the present study, during the period of October 2018 to July 2020, 4 clinical cases with high morbidity (5%-20%) and mortality (2%-10%), caused by the co-infection of REV and vv+ MDV-like strains, were diagnosed and analyzed by histopathological observation, cell cultures and detection with ELISA and IFA, and the PCR and by sequencing of the isolates' genes. Sequencing and the sequence analysis on the complete genomes of the REV strains and the meq genes of the MDV strains were performed. The results, based on the complete genome, LTR, gag, pol, and env genes' nucleotide sequences of the REV strains, showed that the REV isolates and 68.0 % (17/25) of the reference strains were in a same branch, and all had a high sequence similarity (>99.0%). The similarities between the four isolates and a vv+MDV strain GX18NNM4 were very high, up to 99.3-99.8%. Also, the amino acid residuals at locations 71, 77, 80, 115, 139, 176, and 217 were all the same as A, E, Y, A, A, R, and A, respectively, in the meq gene of the four MDV isolates. In addition, the substitutes at P176R and P217A interrupted the stretches of the proline-rich repeat PPPP, indicating that these strains belonged to the vv+ MDV-like category. Our findings indicated that the more recent and frequent reemergence of REV and the subsequent co-infection with vv+ MDV-like strain has become one of the causes of the clinical outbreaks of tumors and is undoubtedly a threat to the poultry industry in southern China.


Assuntos
Coinfecção , Herpesvirus Galináceo 2 , Doença de Marek , Doenças das Aves Domésticas , Vírus da Reticuloendoteliose , Animais , Galinhas , China/epidemiologia , Coinfecção/epidemiologia , Coinfecção/veterinária , Herpesvirus Galináceo 2/genética , Doença de Marek/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Vírus da Reticuloendoteliose/genética
7.
Virus Evol ; 7(1): veab037, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34026272

RESUMO

Avian leukosis virus subgroup J (ALV-J) has infected a variety of birds, causing major economic losses in China. Understanding the comprehensive criteria of classification and nomenclature of ALV-J would be useful for the investigation of the viral evolution and also for the prevention and control of this infection. An in-depth analysis of the genetic diversity of ALV-J was performed in the present study. Four hundred and seventy-five sequences of the gp85 gene, including thirteen of avian endogenous retrovirus designated ev/J and 462 of ALV-J, were used in the phylogenetic and the evolutionary distance analysis for this classification. The study identified that the current ALV-J strains were divided into two first-order clades (Clades 1 and 2) and three second-order clades (Clades 1.1, 1.2 and 1.3). The current Chinese ALV-J strains are predominantly in Clade 1.3, and the Chinese and Egyptian chicken flocks have been facing the emerging Clade 2 viruses. This system pioneers the classification efforts for ALV-J, which uses Pilot tree for rapid classification of the new isolates and also the addition of possible new clades. The proposed unified classification system will facilitate future studies of ALV-J epidemiology and genetic evolution and of the comparison of sequences obtained across the world.

8.
Poult Sci ; 100(4): 101027, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33647716

RESUMO

One avian leukosis virus of subgroup J (ALV-J) strain GX14YYA1 was isolated from a commercial bivalent Newcastle disease (ND)-infectious bronchitis (IB) vaccine in our previous study. To evaluate the pathogenicity of the ALV-J-contaminated vaccine on commercial chickens, day-old Three-Yellow chicks in group I were vaccinated with ALV-J-contaminated bivalent ND-IB live vaccine by intranasal and eye drop at 1-day-old for the primary vaccination and at 7-day-old for the secondary vaccination. Groups II and III were kept as the normal vaccination group with the noncontaminated ND-IB vaccine and blank control groups, respectively. The birds of different groups were maintained separately in isolators for 175 d. The first viremia was detected at 4 wk of age and 20% (2/10) of the birds maintained viremia during 11 to 25 wk of age. At the same time, the birds in group I experienced a significant suppression of body weight gain when compared with those of groups II and III (P < 0.05). In addition, the birds in group I showed obvious ALV-J hemangioma-type anatomical lesions in the liver and tumors were observed in the abdominal cavity. The results demonstrated that the ALV-J contaminated commercial live vaccines can induce pathogenicity in commercial Three-Yellow chickens and indicate that ALV-J-contaminated commercial live vaccines could be one of the transmission routes of ALV-J to commercial chickens.


Assuntos
Vírus da Leucose Aviária , Leucose Aviária , Doenças das Aves Domésticas , Animais , Galinhas , Virulência
9.
Transbound Emerg Dis ; 68(6): 3574-3587, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33354907

RESUMO

Marek's disease (MD) continues to threaten the sustainability of the world poultry industry. In this study, the sequences of the meq gene of 220 MDV strains isolated during the years 1964-2020 were analysed, including 50 from our group plus 170 isolates from the GenBank. Analyses, using phylogenetic trees, amino acid (aa)-mutation screening, evolutionary studies and transmission dynamics were all performed. All strains were divided into two clusters (Clusters 1 and 2), and Cluster 1 includes the mild strains, the vaccine strains and the foreign virulent strains, while Cluster 2 was dominated by the Chinese field strains. Our study identified that the Chinese field strains in Cluster 2 during the years 1995-2020 likely originated in the 1980s from abroad, and the estimated genetic diversity of these strains experienced two growth phases in the years 2005-2007.5 and 2015-2017. Viral phylogeography identified 3 major geographic provincial regions for the Chinese field strains of Cluster 2: the Northeastern Region (Jilin, Liaoning and Heilongjiang), the East-central Region (Henan, Shandong and Jiangsu) and the Southern Region (Guangxi, Guangdong and Yunnan). The spread of Northeastern strains to East-central chicken flocks and the further spread from Guangxi to Guangdong are strongly indicated. The emergence of the mutations A88T and Q93R together in the Southern strains during the years 2017-2020 with molecular characteristics of vv+ MDV were also found later than those in the Northern strains. Overall, the Chinese field strains in Cluster 2 in southern China in recent years have been rapidly evolving. Guangxi Province has become an epicentre for these viruses and the chicken flocks in the Southern region have been facing the adverse effects of the emerging vv+ MDV.


Assuntos
Doença de Marek , Doenças das Aves Domésticas , Animais , Galinhas , China/epidemiologia , Filogenia , Doenças das Aves Domésticas/epidemiologia
10.
Poult Sci ; 100(1): 19-25, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33357681

RESUMO

Both reticuloendotheliosis and Marek's disease are neoplastic diseases of chickens caused by reticuloendotheliosis virus (REV) and Marek's disease virus (MDV), respectively. The infection of REV or MDV may lead to clinical tumors and also result in immunosuppression and easily allow secondary infection by other pathogens. Here, we investigated a breeder flock of three-yellow chickens in southern China that had been vaccinated with CVI988/Rispens at hatching and had experienced depression, weakness, reduction in weight gain, and an increased death rate after 120 d of age. The morbidity and mortality were 20% and 10%, respectively, at 140 d of age when this infection was diagnosed. The necropsy of the birds revealed significant tumor-like lesions in the heart, liver, spleen, and ceca. Peripheral blood lymphocytes and tumor-like tissues were sampled for PCR detection and for histopathological observation, for virus isolation and the subsequent immunofluorescent assay on the cell cultures and for gene sequencing of the isolated viruses. A REV isolate GX18NNR1 and a MDV isolate GX18NNM5 were both recovered from the sampled bird. Further phylogenetic analysis based on the env gene of REV and the meq gene of MDV demonstrated that GX18NNR1 was closely related to the reference REV strain MD-2, which was isolated from a contaminated commercial turkey herpesvirus vaccine. In addition, the GX18NNM5 was found to belong to the Chinese very virulent MDV strains' cluster. The coinfection of REV and MDV may contribute to tumor outbreaks with high morbidity and mortality in three-yellow chicken flocks.


Assuntos
Coinfecção , Doença de Marek , Neoplasias , Doenças das Aves Domésticas , Infecções por Retroviridae , Infecções Tumorais por Vírus , Animais , Galinhas , China/epidemiologia , Coinfecção/veterinária , Surtos de Doenças/veterinária , Herpesvirus Galináceo 2/genética , Doença de Marek/epidemiologia , Doença de Marek/patologia , Neoplasias/etiologia , Neoplasias/veterinária , Neoplasias/virologia , Filogenia , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/patologia , Vírus da Reticuloendoteliose/classificação , Vírus da Reticuloendoteliose/genética , Infecções por Retroviridae/complicações , Infecções por Retroviridae/epidemiologia , Infecções por Retroviridae/patologia , Infecções por Retroviridae/veterinária , Infecções Tumorais por Vírus/complicações , Infecções Tumorais por Vírus/epidemiologia , Infecções Tumorais por Vírus/patologia , Infecções Tumorais por Vírus/veterinária
11.
Vet Microbiol ; 250: 108862, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33007608

RESUMO

The differences among different sub-groups of the avian leukosis virus (ALV) genome are mainly concentrated in the env gene, which binds to cell-specific receptors and determines the characteristics of viral tropism and pathogenicity. In this study, two rescued viruses rGX15MM6-2 (ALV of subgroup J, ALV-J) and rGX14FF03 (ALV of subgroup B, ALV-B) and a recombinant virus rALV-B-Jenv (ALV-B's backbone with ALV-J's env) were generated and tested utilizing both in vitro and in vivo experiments. The results showed that the replication ability of the viruses released in DF-1 cell cultures was listed in order as rGX15MM6-2 > rALV-B-Jenv > rGX14FF03. rGX15MM6-2 caused the most serious suppression of body weight gain, exhibited a significant negative effect on the development of immune organs (P < 0.05) and lower antibody responses to vaccinations with the commercial oil-emulsion vaccines (OEVs) (P<0.05) in the challenged chickens. The viral detection showed that the positive rate in blood from the birds infected with rALV-B-Jenv were respectively higher than those from the birds infected with rGX14FF03 (P < 0.05). At 25 wpi, similar tumors were found in the abdominal cavity of the birds in rGX15MM6-2 and rALV-B-Jenv groups. The results demonstrated that the ALV-J env gene significantly increases the pathogenicity of the recombinant ALV-B. With the increasing incidence of co-infections of different subgroups of ALV in the field, the possibility of viral recombination is increasing and demands further study.


Assuntos
Vírus da Leucose Aviária/genética , Vírus da Leucose Aviária/patogenicidade , Leucose Aviária/virologia , Genes env , Replicação Viral , Animais , Leucose Aviária/imunologia , Vírus da Leucose Aviária/classificação , Linhagem Celular , Galinhas/virologia , Fibroblastos/virologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/virologia , Recombinação Genética , Tropismo Viral , Viremia , Virulência
12.
Viruses ; 12(9)2020 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-32962247

RESUMO

Marek's disease (MD) is an infectious malignant T-cell lymphoma proliferative disease caused by Marek's disease virus (MDV). In recent years, the emergence of very virulent (vv) and/or very virulent plus (vv +) strains of MDV in the field has been suggested as one of the causes of vaccination failure. The pathogenicity of the MDV strain GX18NNM4, isolated from a clinical outbreak in a broiler breeder flock that was vaccinated with CVI988/Rispens, was investigated. In the vaccination-challenge test, GX18NNM4 was able to break through the protections provided by the vaccines CVI988 and 814. It also significantly reduced body weight gain and caused marked gross lesions and a large area of infiltration of neoplastic lymphocyte cells in the heart, liver, pancreas, etc. of the infected birds. In addition, the expressions of programmed death 1 (PD-1) and its ligand, programmed death ligand 1 (PD-L1), in the spleens and cecal tonsils (CTs) of the unvaccinated challenged birds were significantly increased compared to those in the vaccinated challenged birds, indicating that the PD-1/PD-L1 pathway is related to immune evasion mechanisms. The results showed that the GX18NNM4 strain could cause severe immunosuppression and significantly decrease the protections provided by the current commercial vaccines, thus showing GX18NNM4 to be a vv + MDV strain.


Assuntos
Herpesvirus Galináceo 2/patogenicidade , Vacinas contra Doença de Marek/imunologia , Doença de Marek/prevenção & controle , Animais , Antígeno B7-H1/metabolismo , Galinhas/virologia , Tolerância Imunológica , Terapia de Imunossupressão , Doença de Marek/patologia , Doença de Marek/virologia , Doenças das Aves Domésticas/virologia , Receptor de Morte Celular Programada 1/metabolismo , Baço/imunologia , Vacinação/veterinária , Carga Viral
13.
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
14.
Poult Sci ; 99(7): 3469-3480, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32616241

RESUMO

During the process of transmission and spread of avian leukosis virus subgroup J (ALV-J) in chickens worldwide, the viral genome is constantly changing. A comprehensive and systematic study of the evolutionary process of ALV-J in China is needed. In this study, we amplified the full-length viral cDNA sequences of 16 ALV-J isolates of Yellow-chicken origin and analyzed and compared these sequences with another 69 ALV-J strains isolated during the years 1988-2018. These isolates were then sorted into 2 clusters: cluster I included isolates that mainly originated from the layers and White-feather broilers from northern China; cluster II included isolates mainly from the Yellow-chicken, most of them being from southern China. According to the sequence homologies of the whole genome and gag, pol, gp85, and gp37 genes, the ALV-J strains are more likely to randomly change in different directions from the original strain HPRS-103 as time passes. The results of entropy analysis of the sequences of gag, pol, and env revealed that the env gene had the largest variation, and the gag gene nonconserved sites are mainly concentrated in p19, p10, and p12. In addition, 84.71% (72/85) of the isolates had the 205-nucleotide (nt) deletion in the 3'UTR region, and 30.59% (26/85) of the isolates had the 125-nt to 127-nt deletion in the E element. Our study provides evidence for the coexistence of 2 extremely different clusters of ALV-J prevailing in China and in some other countries during the period of 1988-2018 and implies that the clusters are highly dependent on the host genetic background and the geographic location.


Assuntos
Vírus da Leucose Aviária/genética , Leucose Aviária/virologia , Galinhas , Doenças das Aves Domésticas/virologia , Análise de Sequência de DNA/veterinária , Animais , China , DNA Complementar/análise , DNA Viral/análise , Geografia , Interações Hospedeiro-Patógeno
15.
Vet Microbiol ; 244: 108683, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32402336

RESUMO

In order to evaluate the influence of the vertical transmission of avian leukosis virus (ALV) from J subgroup (ALV-J) positive parents on the vaccine efficacy of Marek's disease virus (MDV), ALV-J positive male breeders × female breeders of Three-yellow chickens and the ALV negative male breeder × the negative female breeders were used respectively for crossbreeding to produce eggs and the hatching offspring. The commercial CVI988/Rispens vaccine was used to vaccinate the crossbred offspring at 1-day-old. At 7-days-old, the birds were inoculated with the inactivated oil-emulsion vaccines (OEVs) AIV-H5 monovalent and NDV + AIV-H9 bivalent, respectively. Then the birds were challenged with a Chinese very virulent (vv) MDV field strain GXY2 at 14-day-old. The results showed that the viral load of the challenged GXY2 in the offspring from the ALV-J positive breeders was significantly higher than that from the ALV-negative breeders' (P < 0.05), and the mortality and tumor incidence of offspring from the ALV-J positive breeders were higher than those of the ALV-negative breeders. Also the offspring of the ALV-J positive breeders exhibited a significant negative effect on the development of the immune organs (P < 0.05) and lower antibody responses to the vaccinations with the commercial OEVs (P<0.05). The MD vaccine protective index in the offspring from the ALV-J positive breeders was lower than that from the ALV-negative breeders. The results of the study demonstrated that the vertical transmission of ALV from the ALV-J positive parents caused severe immunosuppression and significantly reduced the Marek's disease vaccine efficacy in Three-yellow chickens.


Assuntos
Leucose Aviária/imunologia , Leucose Aviária/transmissão , Terapia de Imunossupressão/veterinária , Transmissão Vertical de Doenças Infecciosas , Vacinas contra Doença de Marek/imunologia , Animais , Vírus da Leucose Aviária/patogenicidade , Cruzamento , Galinhas/imunologia , Galinhas/virologia , Feminino , Masculino , Doença de Marek/imunologia , Doença de Marek/prevenção & controle , Aves Domésticas/imunologia , Aves Domésticas/virologia , Doenças das Aves Domésticas/imunologia , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/virologia , Potência de Vacina , Carga Viral
16.
Poult Sci ; 98(12): 6497-6504, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31549168

RESUMO

One natural recombinant avian leukosis virus (ALV) strain GX14DJ3-18 was isolated from a native gamecock by DF-1 cell culture and identified with Polymerase Chain Reaction (PCR), immunofluorescence assay and the viral genome's nucleotide sequencing. This strain was revealed as a novel recombinant virus with nucleotide sequence similarities of 95.4% Long Terminal Repeated (LTR), 95.8% 5', UTR, 97.9% gag, and 92.9% 3'untranslated regions (UTR) in ALV-J. Also we found sequence similarities of 99.3% pol and 99.0% gp37 in ALV-E, and 89.9% gp85 in ALV-A. The simulated congenital infection with GX14DJ3-18 in Three-Yellow chickens exhibited a significant negative effect on the development of immune organs (P < 0.05). Also, lower antibody responses were found to vaccinations with the commercial vaccines of Newcastle disease virus and with subtypes H5 and H9 of avian influenza virus (P < 0.05). The incidence of tumor or tumor-like lesions in the challenged birds was 14.28% (5/35), while none were observed in the un-challenged control group (0/35). These results suggested that GX14DJ3-18 is a novel recombinant ALV that can induce pathogenicity in the commercial Three-Yellow chickens. We speculated that cross-provincial sales of gamecocks in which ALVs have not been eradicated thoroughly might be a potential route for the transmission of ALVs to commercial chickens.


Assuntos
Vírus da Leucose Aviária/isolamento & purificação , Vírus da Leucose Aviária/patogenicidade , Leucose Aviária/virologia , Galinhas , Genoma Viral , Doenças das Aves Domésticas/virologia , Animais , Sequência de Bases , China , Alinhamento de Sequência , Virulência
17.
Transbound Emerg Dis ; 66(1): 312-316, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30248239

RESUMO

A total of 81 clinical cases of suspected tumours were submitted to our laboratory from Yellow chicken farms in southern China during the years 2010 through 2017. The tumour-like tissue samples were closely examined for common oncogenic avian viruses in cell culture and further analysed using polymerase chain reaction (PCR). During 2010-2012, Marek's disease virus (MDV) mono-infection was found to be the dominant cause of the tumour incidences (52.4%, 11/21) followed by co-infection of MDV+ALVs (19.1%, 4/21). Starting from the year 2013 the mono-infection of avian leucosis virus subgroup J (ALV-J) became the dominant agent of the tumour cases (83.3%, 5/6). During the most recent four years (2014-2017), co-infections involving ALV-J and MDV or between ALV subgroups have increased (23.4% and 18.5%, respectively), but each of the co-infections was still slightly lower than the ALV-J mono-infection incidence (33.3%). In contrast to the dominant MDV mono-infection cases before 2013, more recently, the emerging ALV-J mono-infection and ALV-J co-infections were largely responsible for the occurrence of avian virus-induced tumour incidences in the commercial local Yellow breeds of chickens in southern China. These results indicate that eradication measures against ALV on all chicken farms, especially on farms with the Yellow chickens, ought to be enhanced to reverse this trend.


Assuntos
Vírus da Leucose Aviária/fisiologia , Leucose Aviária/epidemiologia , Galinhas , Neoplasias/veterinária , Doenças das Aves Domésticas/epidemiologia , Animais , Leucose Aviária/virologia , China/epidemiologia , Coinfecção/epidemiologia , Coinfecção/veterinária , Coinfecção/virologia , Incidência , Neoplasias/epidemiologia , Neoplasias/virologia , Doenças das Aves Domésticas/virologia
18.
J Am Chem Soc ; 140(44): 14799-14806, 2018 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-30351925

RESUMO

Early 3d transition metals are not focal catalytic candidates for many chemical processes because they have strong affinities to O, N, C, or H, etc., which would hinder the conversion of those species to products. Metallic Mn, as a representative, undergoes nitridation under ammonia synthesis conditions forming bulk phase nitride and unfortunately exhibits negligible catalytic activity. Here we show that alkali or alkaline earth metal hydrides (i.e., LiH, NaH, KH, CaH2 and BaH2, AHs for short) promotes the catalytic activity of Mn nitride by orders of magnitude. The sequence of promotion is BaH2 > LiH > KH > CaH2 > NaH, which is different from the order observed in conventional oxide or hydroxide promoters. AHs, featured by bearing negatively charged hydrogen atoms, have chemical potentials in removing N from Mn nitride and thus lead to significant enhancement of N2 activation and subsequent conversion to NH3. Detailed investigations on Mn-LiH catalytic system disclosed that the active phase and kinetic behavior depend strongly on reaction conditions. Based on the understanding of the synergy between AHs and Mn nitride, a strategy in the design and development of early transition metals as effective catalysts for ammonia synthesis and other chemical processes is proposed.

19.
Arch Virol ; 163(2): 377-389, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29086106

RESUMO

ALV-J has caused the most serious losses to the poultry industry in China. The gp85-coding sequence of ALV-J is known to be prone to mutation, but any association between the gp85 gene and breed of chicken remains unclear. A comprehensive and systematic study of the evolutionary process of ALV-J in China is needed. In this study, we compared and analyzed gp85 gene sequences from 198 ALV-J isolates, originating from China, USA, UK and France during 1989-2016. These were sorted into five clusters. Cluster 1, 2, 3, 4 and 5 included isolates from chicken types of different genetic backgrounds, e.g. white-feather broiler, Guangxi indigenous chicken breeds, Yellow chickens and layer chickens respectively. A correlation comparison of amino acid sequence similarities in the gp85 protein among the five clusters showed significant differences (P < 0.01) with the exception being when the third and fifth cluster were compared (P > 0.05). Results of entropy analysis of the gp85 sequences revealed that cluster 3 had the largest variation and cluster 1 had the least variation. The N-glycosylation sites in the majority of isolates numbered 14, 16, 17, 16 and 16, respectively, with regards to clusters 1-5. In addition, 5 isolates from cluster 3 had one more glycosylation site than the other isolates from cluster 3. Our study provides evidence that there were five extremely different ALV-J clusters during 1989-2016 and that the gp85 genes isolated from indigenous chicken breed isolates had the largest variation.


Assuntos
Vírus da Leucose Aviária/genética , Leucose Aviária/virologia , Evolução Molecular , Variação Genética , Doenças das Aves Domésticas/virologia , Proteínas do Envelope Viral/genética , Animais , Vírus da Leucose Aviária/classificação , Vírus da Leucose Aviária/isolamento & purificação , Galinhas , China
20.
Virus Genes ; 53(6): 868-875, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28718045

RESUMO

Since 2014, cases of hemangioma associated with avian leukosis virus subgroup J (ALV-J) have been emerging in commercial chickens in Guangxi. In this study, four strains of the subgroup J avian leukosis virus (ALV-J), named GX14HG01, GX14HG04, GX14LT07, and GX14ZS14, were isolated from chickens with clinical hemangioma in 2014 by DF-1 cell culture and then identified with ELISA detection of ALV group specific antigen p27, the detection of subtype specific PCR and indirect immunofluorescence assay (IFA) with ALV-J specific monoclonal antibody. The complete genomes of the isolates were sequenced and it was found that the gag and pol were relatively conservative, while env was variable especially the gp85 gene. Homology analysis of the env gene sequences showed that the env gene of all the four isolates had higher similarities with the hemangioma (HE)-type reference strains than that of the myeloid leukosis (ML)-type strains, and moreover, the HE-type strains' specific deletion of 205-bp sequence covering the rTM and DR1 in 3'UTR fragment was also found in the four isolates. Further analysis on the sequences of subunits of env gene revealed an interesting finding: the gp85 of isolates GX14ZS14 and GX14HG04 had a higher similarity with HPRS-103 and much lower similarity with the HE-type reference strains resulting in GX14ZS14, GX14HG04, and HPRS-103 being clustered in the same branch, while gp37 had higher similarities with the HE-type reference strains when compared to that of HPRS-103, resulted in GX14ZS14, GX14HG04, and HE-type reference strains being clustered in the same branch. The results suggested that isolates GX14ZS14 and GX14HG04 may be the recombinant strains of the foreign strain HPRS-103 with the local epidemic HE-type strains of ALV-J.


Assuntos
Vírus da Leucose Aviária/genética , Galinhas/virologia , Hemangioma/virologia , Doenças das Aves Domésticas/virologia , Regiões 3' não Traduzidas/genética , Animais , Leucose Aviária/virologia , Sequência de Bases , China , Filogenia , Análise de Sequência , Deleção de Sequência/genética
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