phylogenetic study based on the gene of attachment protein (g) avian metapneumovirus from broiler breeder farm in iran, 2013

Background and aims: avian metapneumovirus (ampv) is rna virus responsible for upper respiratory disease in poultry which is usually accompanied by secondary bacterial infections. in iran, some molecular and serological studies indicated that ampv infection occurred in commercial poultry industry. materials and methods: in this study ampv was molecularly identified and characterized in an affected broiler breeder flock. the wellvaccinated flock was suffering from a disease with clinical signs and a drop in egg production. after rna extraction from tracheal and oropharyngeal samples, the presence of viral rna was demonstrated by reverse transcriptionpolymerase chain reaction using primers specific to the attachment glycoprotein(g) gene. positive samples were sequenced and phylogenetic tree based on sequences results was drawn. based on sequences analysis, field strain of ampv was recovered from the flock. results: phylogenetic analysis showed that the virus (pcrlab/hg2013) is located in b subtype cluster and is closely related to the ampv strain that was previously detected in iran (pcrlab/hg2010) and other countries (nigeria, japan and brazil). conclusion: the results showed that field strain of ampv has the potential to cause disease and economic losses in breeder broiler especially during egg production period. it is also concluded that vaccination against ampv may not provide full protection in field situation and other control measurements including biosecurity should be taken.