Investigação de vírus de impacto na sanidade avícola em aves silvestres no Rio Grande do Sul

Abstract

Brazil is the second largest producer of chicken meat, with a 13.14 millions of tons production in 2015 and, about 4 millions of tons were for export. Wild birds, of free life, due to its biological characteristics are capable of carrying pathogenic microorganisms both biologically or mechanically, may thus act as disseminators of several different diseases in industrial, commercial and even domestic poultry production. This study aims at investigating the exposure to Newcastle Disease Virus (NDV), Marek’s Disease and Infectious Bursal Disease (IBDV) in wild birds living near a colonial poultry breeding and, in migratory birds (Calidris fuscicollis and Thalassarche melanophris) captured off the coast of Rio Grande do Sul. The methodology used was the viral genetic material detection using RT-PCR and PCR in cloacal and oropharynx swabs and ELISA serology in total blood samples collected in filter paper. It was not detected the presence of NDV or Marek’s Disease Virus by molecular methods in the wild birds investigated (n=24), NDV and IBDV antibodies were also not detect in immunoenzymatic assays (n=30). All serum samples of Calidris fuscicollis tested (n=58) were negative for NDV and IBDV antibodies. However, 50% (4/8) presented positive results for Marek’s Disease virus antibodies. In Thalassarche melanophris, 100% of the samples returned negative for IBDV and positive for Marek’s Disease Virus. In the present study, no excretion or previous exposure of resident wild birds surveyed to NDV, Marek's disease virus and IBDV was detected by the diagnostic techniques employed, however, in the two migratory species sampled, previous contact with the Marek's Disease Virus was evidenced.