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1.
Comp Immunol Microbiol Infect Dis ; 73: 101565, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33126169

RESUMO

Newcastle disease (ND) is one of the most serious infectious and contagious viral diseases in avian species. Recently, several ND outbreaks in pigeon caused by pigeon paramyxovirus serotype-1 (PPMV-1) have been reported from Iran, but unfortunately, phylogenetic studies have been mostly conducted on partial sequence of NDV fusion (F) gene. In addition, a complete genome data of Iranian PPMV-1 strains are not available. In the present study, a PPMV-1, named Avian avulavirus 1/pigeon/Iran/UT-EGV/2018, isolated from an infected pigeon, was subjected to whole-genome sequencing. The isolate showed an MDT of 74 h, thus categorizing it as mesogenic. The phylogenetic analysis based on the F gene sequence revealed the isolate belongs to XXI.1.1 subgenotype (min 0.9 % and max 3 %). To our knowledge, our study is the first study to publish the complete genome of a PPMV-1 from Iran. According to BLAST results, the whole genome of UT-EGV had high homology with some Russian, Egyptian and Ukrainian strains (the highest was 96.55 %). Additionally, we conducted a phylogenetic analysis on five PPMV-1 that we isolated in 2014 to find that they may belong to a completely unreported subgenotype (6 % distance when compared as a group). The information obtained from this study can be useful in preventive measures, including constructing an effective vaccine against PPMV-1 in Iran.


Assuntos
Columbidae , Genoma Viral , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Animais , Columbidae/classificação , Columbidae/genética , Irã (Geográfico)/epidemiologia , Doença de Newcastle/epidemiologia , Vírus da Doença de Newcastle/classificação , Vírus da Doença de Newcastle/patogenicidade , Filogenia , RNA Viral/genética , RNA Viral/isolamento & purificação , Organismos Livres de Patógenos Específicos
2.
Trop Anim Health Prod ; 51(3): 689-695, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30377950

RESUMO

In this study, the prevalence and spatial distribution of Newcastle disease, infectious bronchitis, and avian influenza have been evaluated in commercial broiler farms in 31 provinces in Iran. In this survey, a total of 233 affected broiler chicken farms were sampled. The infectious bronchitis virus (alone) was detected with highest frequency in 60 farms, and separately or combined with other agents, in 110 farms; Newcastle disease virus, separately, was detected in 28 farms, and in 63 farms separately or combined with other infectious agents; and avian influenza H9N2 was detected in 22 farms separately and in 51 farms separately or concomitant with other infectious agents. The sample tested negative for all H5 serotypes. The results of the present study show that the most prevalent avian viral infectious disease contributing to respiratory syndromes in broiler farms in Iran was infectious bronchitis due to infectious bronchitis virus serotypes variant 2 and 793/B. On the other hand, combined with the alternation of dominant viruses and circulating strains, flocks are exposed to unremitting anamorphic viral infections. Thus, the permanent monitoring of cases that have occurred and the review of vaccination plans of affected flocks every year are some of the necessary measures needed for strategic control of respiratory syndrome in broilers. It is noteworthy that execution of epidemiologic examinations on the cogent factors of prevalence of this syndrome and defeat of vaccination strategy in the flocks is urgent and has to be fulfilled on the definite causes of time.


Assuntos
Galinhas , Infecções por Coronavirus/veterinária , Influenza Aviária/epidemiologia , Doença de Newcastle/epidemiologia , Doenças das Aves Domésticas/virologia , Animais , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Fazendas , Vírus da Bronquite Infecciosa , Vírus da Influenza A Subtipo H9N2 , Irã (Geográfico)/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Prevalência
3.
Avian Pathol ; 47(1): 90-99, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28874068

RESUMO

Newcastle disease is an economically important and highly contagious disease affecting wild and domestic avian species. Despite extensive vaccination efforts within the poultry industry, Newcastle disease virus (NDV) outbreaks causing significant economic losses still occur. Rural chickens may act as a potential reservoir of NDVs for commercial poultry due to poor biosecurity and inadequate vaccination. The aim of this study was to investigate the phylogenetic relationship and molecular characterization of eight NDVs isolated from backyard poultry in Iran during 2011-2013. The complete coding sequence of fusion (F) and haemagglutinin-neuraminidase (HN) genes of eight NDVs were determined and compared with other published NDVs. Based on inter-population distances and phylogenetic topology between available NDV categories, Iranian isolates formed a novel VIIl sub-genotype distinct from previous groups designated in genotype VII. Furthermore, both F and HN genes of the Iranian isolates shared high nucleotide sequence similarity with viruses isolated in China. All viruses analysed contained a polybasic cleavage site motif (111G/RRRQKR↓F117), indicating that all isolates could be categorized as a virulent pathotype. No mutation was observed in the neutralizing epitopes of the F protein. Analysis of amino acids associated with neutralizing antigenic sites within the HN protein revealed that all isolates exhibited a unique amino acid (Q) at position 347. These results emphasize the need for strengthening the biosecurity measures implemented on village flocks and practicing a mandatory vaccination programme for local poultry. Moreover, continuous monitoring of NDVs in different species of birds can help to gain more knowledge about the evolution of this virus and prevent future panzootics.


Assuntos
Galinhas , Genótipo , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/isolamento & purificação , Doenças das Aves Domésticas/virologia , Animais , Surtos de Doenças/veterinária , Irã (Geográfico) , Doença de Newcastle/epidemiologia , Vírus da Doença de Newcastle/patogenicidade , Filogenia , Doenças das Aves Domésticas/epidemiologia , RNA Viral/genética , Análise de Sequência de DNA , Proteínas Virais/genética
4.
Vet Res Forum ; 7(4): 317-321, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-28144423

RESUMO

Avian infectious bronchitis (IB), caused by a gammacoronavirus, is an OIE-listed (List B) disease and characterized by respiratory and renal involvements, causing high mortality, and economic loss in both layers and broilers. In comparison with other diagnostic methods, real-time polymerase chain reaction (RT-PCR) and conventional RT-PCR are potent, more sensitive and faster techniques for infectious bronchitis virus (IBV) detection. This research was conducted to detect IBV using specific primers of IB in three governorates (Basra, Thi-Qar and Muthana) in the south of Iraq. Tracheal specimens were collected from 46 IB suspected commercial broiler flocks. XCE2+ and XCE2- Primers, which amplify all IBV serotypes, were used. Primers MCE1+, BCE1+ and DCE1+ were used to amplify the specific nucleotide sequences of Massachusetts, 793/B and D274 genotypes, respectively. The results of real-time RT-PCR of this study showed that 34 (74.00%) out of 46 infected flocks were positive to IBV. The results of nested PCR showed that 50.00% and 5.89% of positive samples were belonged to genotypes 793/B and Massachusetts, respectively, and the remaining positive (44.11%) were unknown. The results indicate presence of Massachusetts and 793/B IBV strains in commercial broilers in southern Iraq.

5.
Vet Res Forum ; 6(3): 227-31, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26893813

RESUMO

Influenza is a contagious viral disease that is seen in avian, human and other mammals, so its control is important. Vaccination against influenza virus subtype H9N2 is one of the ways in controlling program, for this reason several vaccines has been produced. Recently, application of inactivated oil-emulsion vaccines in poultry for controlling low pathogenic avian influenza is increasing. At present, oils that are used as adjuvant in commercial vaccines are mineral oils, which not only lack immunizing effect, but also produce some detriments. The aim of this study is the evaluation the immunogenicity of vegetable oils, which are more metabolizable and safer than mineral oils. In this study the efficacy of hexanic extracts of fig (Ficus carica) and olive (Olea europaea) fruit and also nano-selenium on the immunogenicity of the inactivated avian influenza virus subtype H9N2 was evaluated in broiler chickens. The results indicated that the prepared emulsions could elicit a little degree of immunity, but they could not inhibit the anamnestic response and infection. With regard to the results, it seems that the intact mixture of fig and olive fruit hexanic extracts could not be administered as an immunoadjuvant in the vaccine, and about nano-selenium. In spite of positive effect on the immunogenicity of avian influenza virus subtype H9N2, it still needs more work.

6.
Arch Virol ; 158(10): 2089-100, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23640582

RESUMO

Infection with avian influenza H9N2 virus is widespread in the Asian poultry industry, resulting in great economic losses due to mortality and a severe decline in egg production. To obtain more-comprehensive genomic data from circulating H9N2 viruses in Iran, we sequenced the whole genomes of early (Ck/IR/ZMT-101/98) and recent (Ck/IR/EBGV-88/10) isolates of this virus in Iran. The M and NS genes of Ck/IR/EBGV-88/10 shared a high level of similarity with a highly pathogenic H7N3 virus isolated from Pakistan. The cleavage site within the HA protein of these viruses contained two different motifs, RSSR and KSSR, which are similar to those found in low-pathogenic viruses. The deduced amino acid sequence of the new isolate contained the mutation Q226L, which is a characteristic of human-type sialic acid influenza receptor binding. An analysis of the viral amino acid sequence of the M2 protein of the recent strain revealed a V27A mutation, which is associated with amantadine resistance in avian influenza virus. The present results emphasize the need for continuous surveillance of H9N2 viruses in poultry and the human population to obtain more information about the nature and evolution of future pandemic influenza viruses.


Assuntos
Variação Genética , Vírus da Influenza A Subtipo H9N2/genética , Influenza Aviária/virologia , Sequência de Aminoácidos , Animais , Regulação Viral da Expressão Gênica/fisiologia , Hemaglutininas/genética , Hemaglutininas/metabolismo , Influenza Aviária/epidemiologia , Irã (Geográfico)/epidemiologia , Neuraminidase/genética , Neuraminidase/metabolismo , Filogenia , Aves Domésticas , Fatores de Tempo
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