Preferencje help
Widoczny [Schowaj] Abstrakt
Liczba wyników

Znaleziono wyników: 18

Liczba wyników na stronie
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników

Wyniki wyszukiwania

help Sortuj według:

help Ogranicz wyniki do:
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
The aim of the study was to develop RT-PCR and Nested-PCR methods for the detection and identification of the West Nile virus in wild birds. The method was based on West Nile Virus genome non-coding region 3'NCR. All the samples were examined with NRT-PCR and also with a commercial West Nile Virus Kit Prodesse™. There was no positive case of West Nile virus infection in the examined samples. All control samples were positive in both methods. The NRT-PCR method proved to be quick and reliable for the testing of wild birds' tissue samples for WNV.
The aim of the study was to determine the effect of field strain, serotype 7 (FAdV-7 JN-5/10), of fowl adenovirus infection on the replication of Rispens/CVI988 strain of Marek's disease virus. Ninety one-day-old SPF chickens were divided into six groups. The chickens from group I were vaccinated against Marek's disease (MD) and 24 h later infected with the adenovirus; chickens from group II were vaccinated and infected simultaneously; chickens from group III were infected with the adenovirus and 24 h after the infection vaccinated against MD. The chickens from groups IV-VI were: control of infection (IV), control of vaccination (V), and neither vaccinated nor infected (VI). After 3, 7, 14, 21, and 28 d post infection, the number of copies of pp38 gene of Rispens strain and hexon gene of FAdV strain was determined in the bursa of Fabricius and liver using real-time PCR. The results indicated that in all cases the replication of Rispens strain was reduced to about 1.0 log₁₀- 3.5 log₁₀ in chickens infected with the adenovirus and vaccinated against MD compared with the chickens only vaccinated. Sixty-three one-day-old SPF chickens infected with adenovirus and vaccinated against MD were challenged with vv MD virus field strain. The protection index in this experiment was 55.6%-77.8%.
West Nile Virus is an icosahedral, spherical, 50 nm in diameter arbovirus from the Flaviviridae family. Its genome contains a single stranded RNA with positive polarity (ssRNA+). Virions are build of three structural proteins: envelope glycoprotein E, core protein C, and membrane protein prM. Apart from them, the virus genome codes seven non-structural proteins: NS1, NS2a, NS2b, NS3, NS4a, NS4b, and NS5. Transmission vectors of WNV are mosquitoes from the Culex pipiens species and other blood-eating insects. Its main reservoir are migrating birds, while humans and other mammals are its occasional host. West Nile Virus shows a high neurotropism and is the cause of morbidity and mortality in different animals and people. During the last ten years it has been identified in Asia, Africa, Europe and both Americas. WNV was also found in Poland. Diagnosis of WNV by the use of specific primers in RT-PCR method allows the identification of the virus strain and its attendant characteristics.
The aim of the study was to determine the influence of simultaneous infection of chicken embryo fibroblasts (CEF) with different doses of adenovirus field strain serotype 7 (FAdV-7 JN-5/10j) and turkey herpesvirus strain FC 126 (FC 126 HVT) on replication of the herpesvirus in in vitro cultures. Three experiments were performed: simultaneous infection of CEF with adenovirus and HVT; inoculation of CEF culture with adenovirus, followed by infection with HVT after 24 h; and inoculation of CEF with HVT, followed by the infection with adenovims 24 h later. In order to detect the presence of HVT and adenovirus strains in CEF culture, SORF 1 and hexon genes were determined, respectively. The infection with adenovirus lowered replication of FC126 HVT in chicken embryo fibroblast.
The study describes successful isolation of 96 fowl adenovirus (FAdV) strains from 789 chickens from 95 flocks. PCR specific for hexon gene encoding L1 loop was conducted. Amplicons were subjected to sequence analysis. The sequences were analysed by the software: BLAST, Geneious 6.0, and MEGA 5, then aligned with different adenovirus strain reference sequences accessible in GenBank database. The examined strains belong to the particular groups and serotypes. The sequences of all adenoviruses were classified into five species (FAdV A-E) and eight serotypes (FAdV-1, FAdV-2, FAdV-4, FAdV-5, FAdV-7, FAdV-8a, FAdV- 8b, and FadV-11).
The strains of adenoviruses were isolated from 356 birds with clinical form of Marek's disease and coinfection with adenoviruses. A hexon gene fragment coding loop LI of adenovirus strains was sequenced and obtained data were analysed with BLAST, Geneious 5.3, and MEGA5 software by comparison with nucleotide sequences of reference strains of fowl adenoviruses (FAdV-1 - FadV-12), two turkey adenoviruses, and two goose adenovirus strains. On this basis, serotypes of adenovirus strains were determined. Sequences of all adenovirus strains isolated from birds infected with Marek's disease virus were classified into six serotypes representing four species. Mostly FAdV-7, FAdV2/11, and FAdV-8a serotypes were found.
13
51%
Two thousand one hundred and forty birds belonging to 39 different species from different locations in Poland were examined. The study has taken place from the early spring till late autumn 2007-2010 when the activity of the mosquitoes was the highest. The brain samples were taken from the birds and whole cellular RNA was isolated, then the RT-PCR and NRT-PCR were performed to detect the presence of West Nile virus (WNV). The obtained results were confirmed by the commercial WNV Kit. No genetic material of WNV was found in the examined samples.
Pierwsza strona wyników Pięć stron wyników wstecz Poprzednia strona wyników Strona / 1 Następna strona wyników Pięć stron wyników wprzód Ostatnia strona wyników
JavaScript jest wyłączony w Twojej przeglądarce internetowej. Włącz go, a następnie odśwież stronę, aby móc w pełni z niej korzystać.