Macedonian Veterinary Review (Jul 2013)
Classical and molecular characterization of pigeon paramyxovirus type 1 (PPMV-1) isolated from backyard poultry – first report in Macedonia
Abstract
Aim of this study was to characterize pigeon variant of Newcastle disease virus (NDV) isolated from backyard poultry using classical and molecular methods. In standard hemagglutination inhibition (HI) test both polyclonal NDV antiserum and monoclonal antibodies 161/617 specific for pigeon variants of NDV showed inhibition of heamagglutination of the isolated virus. Intracerebral pathogenicity index (ICPI) has shown that the isolate is mesogenic virus (ICPI = 0.81). One-step RT-qPCR for detection of M gene was performed indicating a presence of NDV and RT-qPCR for discrimination between lentogenic and velogenic strains based on F gene was also performed indicating a presence of virulent NDV. A portion of the F gene was amplified and sequenced for determination of virulence and phylogenetic characterization. The F protein cleavage site sequence of the isolate had multiple basic amino acids at residues 112–116 and a phenyl alanine at residue 117 (112RRQKR*F117) which is typical for velogenic strains. The nucleotide sequence of 374 bp was aligned to begin at nt 47 and finish at 420 immediately after the cleavage site and compared with other reference strains from the region and worldwide. In the phylogenetic tree, the isolate clustered into genotype VIb, typical for PPMV-1. This strain is phylogenetically very similar to other PPMV-1 isolated from pigeons in Macedonia. Poultry infected with PPMV-1 can spread the virus in the absence of clinical signs, thus PPMV-1’s are constant threat to domestic poultry. This is the first report of evidenced spillover of PPMV-1 into poultry in Macedonia.
