The Experts below are selected from a list of 21 Experts worldwide ranked by ideXlab platform
Chen Xiao-yue - One of the best experts on this subject based on the ideXlab platform.
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Replication kinetics of duck plague virus virulent strain in parenchymatous organs of experimentally infected ducklings
Chinese journal of veterinary science, 2008Co-Authors: Chen Xiao-yueAbstract:The kinetics of virus load was examined in ducklings infected with virulent duck plague virus (DPV) by the mucosal or systemic route at 20 days of age.Two infected birds were chosen randomly for sampling at each of ten sampling time between 10 min and 15 days postinoculation (p.i.),and the distribution and replication of DPV in the parenchymatous organs,including heart,liver,spleen,lung,kidney,brain,thymus,bursa of Fabricius and Glands of Harder,were examined using real-time quantitative TaqMan-MGB polymerase chain reaction.The results showed that the distribution of DPV in multiple organs examined have a close correlation with the infected administration and the anatomized structure of duck,and the levels of viral DNA could be first detected in organs of subcutaneously infected birds.The significant numbers of virus genomes were detected in subcutaneously infected organs at 30 min p.i.,including liver,spleen,thymus,bursa,Harder Gland,lung,brain and kidney,and were also detected in lung and bursa of orally infected birds,and heart and Harder Gland of nasally infected birds.By 90 min p.i.,the significant levels of DPV were detected in all organs examined independent of the infected administration.The successive importance of immune organs in resistance the DPV infection was spleen,thymus,bursa,and Harder Gland.The spread and viral levels of DPV in organs,including spleen,thymus,bursa,have a close correlation with the progression of disease.The virus loads in individual organs of subcutaneously infected birds were relatively higher at the same time point,compare with that in orally or nasally infected birds.The peak levels of DPV in bursa and kidney of dead ducklings were higher among organs examined.
Silveira Flavio - One of the best experts on this subject based on the ideXlab platform.
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Pathogenicity of a new italian genotype of Infectious Brusal Diases Virus in SPF chickens
2019Co-Authors: Silveira FlavioAbstract:Infectious Bursal Disease (IBD) is a highly contagious immunosuppressive disease of chickens caused by a Birnaviridae (IBDV). The ITA genotype was first detected in 2011 in Italy in IBD-live vaccinated chickens. Full genome characterization confirmed ITA to be a genetically dis-tinctive IBDV. The aim of the study was to determine the pathogenicity of the ITA genotype in SPF chickens. Birds were housed in poultry isolators and inoculated at 35 days of life with ITA or STC IBDV strains. A control group was housed in analogous conditions and inoculated with sterile water. All groups were daily observed for clinical signs up to 28 days post-inoculation (dpi). At 0, 7, 14, 21 and 28 dpi birds were bled for IBDV antibody detection by an ELISA Kit. At 2, 4, 7, 14, 21 e 28 dpi 5 birds from each of the inoculated groups, and 3 from the control group, were euthanized and subjected to necropsy. Bursal and Thymus indexes were calculated; histological sections were examined and scored; viral tissue distribution determined by qRT-PCR in the bursa of Fabricious (BF), thymus, kidney, cecal tonsils, spleen, proventriculus, Harder Gland and bone marrow. No clinical signs, nor mortality were recorded in any group dur-ing the study. BF of both inoculated groups showed enlargement and oedema in the acute phase of the infection (2 dpi), followed by atrophy, which lasted until the end of the trial. Microscopic lesions of the BF of ITA IBDV inoculated birds consisted in lymphocyte depletion, cystic cavi-ties and poor regeneration process. Viral RNA was persistently detected until the end of the tri-al in lymphoid tissues. The study showed that ITA genotype, though it has a subclinical course, causes a severe and persistent damage of BF, therefore, its circulation in broilers might be a threat for the poultry industry
Catelli E. - One of the best experts on this subject based on the ideXlab platform.
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Pathogenicity of a new Italian genotype of infectious bursal disease virus in SPF chickens.
2017Co-Authors: Lupini C., Silveira F., Berto G., Franzo Giovanni, Cecchinato Mattia, Mescolini G., Catelli E.Abstract:Infectious bursal disease virus (IBDV) genotype ITA was first detected in 2011 in Italy in IBD- live vaccinated broilers. Full genome caracterization confirmed ITA to be a genetically distinctive IBDV genotype. In particular peculiar molecular characteristics were observed in key positions of the VP2 hypervariable region, which affect charged or potentially glycosylated amino acids virtually associated with important changes in virus properties. The aim of this study was to determine the pathogenicity of ITA genotype in SPF chickens. 84 Birds were housed in poultry isolators and inoculated at 35 days of life with ITA IBDV strain Italy/1829/2012 (40 birds) or a classical reference strain (40 birds). 28 controls were contextually mock inoculated with sterile water. All groups were daily observed for clinical signs up to 28 days post-infection (dpi). At 0, 7, 14, 21 and 28 dpi birds were bled for IBDV antibody detection by a commercial ELISA Kit. At 2, 4, 7, 14, 21 e 28 dpi 5 birds from each of the inoculated groups, and 3 from the control group, were euthanized and subjected to post-mortem examination. Bursal and Thymus indexes were calculated; histopathology of the Bursas of Fabricious was carried out and viral tissue distribution determined by qRT-PCR in the following tissues: bursa of Fabricious, thymus, kidney, cecal tonsils, spleen, proventriculus, Harder Gland and bone marrow. No clinical signs, nor mortality were recorded in any group during the study. Bursas of Fabricious of both IBDV inoculated groups showed enlargement and oedema in the acute phase of the infection (2 dpi), followed by atrophy, which lasted until the end of the trial. Atrophy of the Bursas appeared earlier and was more substantial in birds inoculated with the ITA strain compared to the ones inoculated with the Classical strain. Histopatology of the Bursas showed lymphocyte depletion, cystic cavities and poor regeneration process. Viral RNA was persistently detected until the end of the trial in bursal tissues and in most of the tissues collected. The study showed that ITA genotype, though it has a subclinical course, causes a severe and persistent damage of Bursa tissues. Therefore its circulation in broilers might be a threat for the poultry industry
Lupini C. - One of the best experts on this subject based on the ideXlab platform.
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Pathogenicity of a new Italian genotype of infectious bursal disease virus in SPF chickens.
2017Co-Authors: Lupini C., Silveira F., Berto G., Franzo Giovanni, Cecchinato Mattia, Mescolini G., Catelli E.Abstract:Infectious bursal disease virus (IBDV) genotype ITA was first detected in 2011 in Italy in IBD- live vaccinated broilers. Full genome caracterization confirmed ITA to be a genetically distinctive IBDV genotype. In particular peculiar molecular characteristics were observed in key positions of the VP2 hypervariable region, which affect charged or potentially glycosylated amino acids virtually associated with important changes in virus properties. The aim of this study was to determine the pathogenicity of ITA genotype in SPF chickens. 84 Birds were housed in poultry isolators and inoculated at 35 days of life with ITA IBDV strain Italy/1829/2012 (40 birds) or a classical reference strain (40 birds). 28 controls were contextually mock inoculated with sterile water. All groups were daily observed for clinical signs up to 28 days post-infection (dpi). At 0, 7, 14, 21 and 28 dpi birds were bled for IBDV antibody detection by a commercial ELISA Kit. At 2, 4, 7, 14, 21 e 28 dpi 5 birds from each of the inoculated groups, and 3 from the control group, were euthanized and subjected to post-mortem examination. Bursal and Thymus indexes were calculated; histopathology of the Bursas of Fabricious was carried out and viral tissue distribution determined by qRT-PCR in the following tissues: bursa of Fabricious, thymus, kidney, cecal tonsils, spleen, proventriculus, Harder Gland and bone marrow. No clinical signs, nor mortality were recorded in any group during the study. Bursas of Fabricious of both IBDV inoculated groups showed enlargement and oedema in the acute phase of the infection (2 dpi), followed by atrophy, which lasted until the end of the trial. Atrophy of the Bursas appeared earlier and was more substantial in birds inoculated with the ITA strain compared to the ones inoculated with the Classical strain. Histopatology of the Bursas showed lymphocyte depletion, cystic cavities and poor regeneration process. Viral RNA was persistently detected until the end of the trial in bursal tissues and in most of the tissues collected. The study showed that ITA genotype, though it has a subclinical course, causes a severe and persistent damage of Bursa tissues. Therefore its circulation in broilers might be a threat for the poultry industry
Jiang L - One of the best experts on this subject based on the ideXlab platform.
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Pathogenicity study of infectious laryngotracheitis virus LJS09
Chinese Journal of Preventive Veterinary Medicine, 2015Co-Authors: Jiang LAbstract:In order to identify the pathogenicity of the infectious laryngotracheitis virus(ILTV) LJS09 isolated from Jiangsu province in 2009, SPF chickens were artificially infected with ILTV LJS09 at a dose of 102EID50. The results showed that the dyspnea, obvious lesions of throat and trachea, and typical histopathological changes appeared in the infected chickens at 4 to 6days post-infection(dpi), with the clinical index up to 1.4, and the morbidity and mortality of 80% and 10%, respectively. The antibody seroconversion rate in infected chickens was 30% at 8 dpi and 100% at 20 dpi. In addition, ILTV LJS09 widely distributed in the internal organs of infected chickens detected by real-time PCR, and the main tissue tropism were the throat,trachea, Harder Gland, brain, cecum and proventriculus. In conclusion, according to the clinical index, morbidity and mortality, the ILTV LJS09 was high pathogenicity to chickens.
