Serological, molecular detection, and characterization of avian paramyxovirus type...
| Grant number: | 11/09019-0 |
| Support type: | Regular Research Grants |
| Duration: | June 01, 2012 - May 31, 2014 |
| Field of knowledge: | Biological Sciences - Microbiology |
| Principal Investigator: | Helena Lage Ferreira |
| Grantee: | Helena Lage Ferreira |
| Home Institution: | Faculdade de Zootecnia e Engenharia de Alimentos (FZEA). Universidade de São Paulo (USP). Pirassununga , SP, Brazil |
| Assoc. researchers: | Clarice Weis Arns ; Márcia Mercês Aparecida Bianchi dos Santos ; Paulo Anselmo Numes Felippe |
Abstract
Newcastle disease virus (NDV), also known as avian paramyxovirus serotype 1 (APMV-1), is a major economic concern for poultry producer world worldwide. Recently, analysis of the genome sizes and sequences of genes has revealed two distinct clades within APMV-1: class I and II. While class I isolates have been recovery from wild birds and samples from live bird markets; class II isolates have been recovery mainly from poultry as virulent forms. Understanding the epidemiology of APMV-1 infections in wild birds has been hampered by the facts that these viruses typically produce no clinical signs and that clade I isolates are often not detected by rapid screening methods. The present study aims to identify the APMV-1 and antibodies against this virus in Brazilian wild birds. To do so, 200 wild birds, mainly waterfowl from Anatidae family, will be sampled in São Paulo and Rio Grande do Sul states. A real time RT-PCR, (RT)²-PCR, for simultaneous moleculardetection of class I and class II viruses will be used in swabs. The multiplex (RT)²-PCR will target the L gene and the M gene of class I and II respectively. The tests will initially be evaluated by using reference strains, and, afterwards, cloacal and oropharyngeal swabs collected from wild birds. The positive samples will be selected and their fusion (F) and hemmaglutinin-neuraminidase (HN) genes will be sequenced. The cleavage site in the fusion protein can predict the pathogenicity of the strain and the F and HN sequences will be used to compare among other APMV-1 sequences by phylogenetic analysis. Finally, the detection of antibodies against APMV-1 will be evaluated by a commercial blocking ELISA using serum from wild birds for the first time. We expect to increase our knowledge about the distribution, genetic diversity, and ecology of AMPV-1 in Brazil with this study. (AU)