title: Subtyping of new Brazilian avian metapneumovirus isolates from chickens and turkeys by reverse transcriptase-nested-polymerase chain reaction.
abstract: The aim of this study was to improve a reverse transcriptase (RT)-nested-polymerase chain reaction (PCR) able to differentiate avian pneumovirus (APV) subtypes A and B, and to characterize new Brazilian isolates. Representative APV strains and clinical field samples from chickens and turkey flocks were amplified in the chicken embryo-related cell line. Viral RNA was extracted from harvested cells, and submitted to cDNA synthesis. The primers utilized for RT-PCR were compatible with the G gene of both the A and B subtypes of APV, while the nested primers were subtype specific. This approach showed that three new APVs from chickens and one from turkeys were subtype A, confirmed by sequencing. This is the first report of APV isolation from turkeys in Brazil. Four other APVs were detected and classified as subtype A by RT-nested-PCR. These optimized techniques could be useful for differentiation of APV subtypes A and B, proving to be a valuable molecular epidemiological tool.
authors.affiliation: Laboratory of Animal Virology, Department of Microbiology and Immunology, Biology Institute, University of Campinas, CEP 13081-970, Campinas, SP, Brazil.
authors.forename: Regina C F
authors.initials: RC
authors.lastname: D'Arce
authors.forename: Lia T
authors.initials: LT
authors.lastname: Coswig
authors.forename: Renata S
authors.initials: RS
authors.lastname: Almeida
authors.forename: Iara M
authors.initials: IM
authors.lastname: Trevisol
authors.forename: Maria C B
authors.initials: MC
authors.lastname: Monteiro
authors.forename: Lavínia I
authors.initials: LI
authors.lastname: Rossini
authors.forename: José
authors.initials: J
authors.lastname: Di Fabio
authors.forename: Hafez M
authors.initials: HM
authors.lastname: Hafez
authors.forename: Clarice W
authors.initials: CW
authors.lastname: Arns
mesh_terms: D000818:Animals; D001483:Base Sequence; D001938:Brazil / Q000453:epidemiology; D002645:Chickens / Q000821:virology; D029121:Metapneumovirus / Q000145:classification* / Q000235:genetics*; D008969:Molecular Sequence Data; D018184:Paramyxoviridae Infections / Q000453:epidemiology / Q000662:veterinary*; D011201:Poultry Diseases / Q000453:epidemiology / Q000821:virology*; D020133:Reverse Transcriptase Polymerase Chain Reaction / Q000379:methods*; D016415:Sequence Alignment; D012689:Sequence Homology, Nucleic Acid; D014422:Turkeys / Q000821:virology