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| Author(s): |
Guilherme Pereira Scagion
Total Authors: 1
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| Document type: | Master's Dissertation |
| Press: | Campinas, SP. |
| Institution: | Universidade Estadual de Campinas (UNICAMP). Instituto de Biologia |
| Defense date: | 2015-06-29 |
| Examining board members: |
Clarice Weis Arns;
Rodolfo Thomé;
Lara Borges Keid
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| Advisor: | Clarice Weis Arns; Helena Lage Ferreira |
| Abstract | |
The avian paramyxovirus type 1 (APMV-1) belongs to family Paramyxoviridae, subfamily Paramyxovirinae, genus Avulavirus. APMV-1 that causes Newcastle disease (ND) is considered a major cause of economic losses to the global poultry industry, because of high mortality and economic embargoes. The Understanding of epidemiology of infections caused by APMV-1 is hampered by the fact that these viruses do not produce clinical signs and often are not detected by rapid diagnostic methods.Wild birds seem to be an important reservoir of these viruses. Recently, analysis of the genome sizes and sequences of genes has revealed two distinct clades within APMV-1: class I and II. The present study aimed to investigate the presence of APMV-1 in wild and feral birds through molecular and serological tests. To this end, 387 samples (194 oropharyngeal swabs and 193 cloacal swabs) of 37 species belonging to 12 orders of birds were tested. A test of real time RT-PCR (RRT-PCR), for the simultaneous detection of viruses of class I and class II was used for molecular detection of genes L and M, respectively. Seven others conventional RT-PCR tests targeting fusion (F) and hemagglutinin-neuraminidase (HN) genes were tested and analytical sensitivity compared with RRT-PCR assay. Those RT-PCR were used for DNA sequencing. Ten out of 387 tested samples were positive by RRT-PCR. Among the positive samples were found, one from Sporophila frontalis an endangered birds species, for which is not yet fully know about AMPV-1 effect. Three samples sequences with the HN gene and eleven with gene F were analyzed phylogenetically and grouped within the genotype II, class II of APMV-1. However, this brazilian group seems to represent a new cluster within this genotype. A competitive ELISA test was tested that performed analytical sensitivity and specificity close to 100% and 10% reproducibility using reference sera. In total, 123 sera were tested by ELISA and also tested by HI test. The occurrence frequency in birds, Anseriforms, especially was 22,73% and 19,51% using HI and ELISA tests, respectively. Those two techniques had a correlation of 0.62. Therefore, our study reiterates the importance of continuing surveillance in wild birds to increase knowledge about epidemiology of AMPV -1 in Brazil (AU) | |
| FAPESP's process: | 13/02059-2 - Serological, molecular detection, and characterization of avian paramyxovirus type-1 (class I and class II) in wild birds |
| Grantee: | Guilherme Pereira Scagion |
| Support Opportunities: | Scholarships in Brazil - Master |