Isolation and characterization of novel goose parvovirus-related virus reveal the evolution of waterfowl parvovirus.

Short beak and dwarfism syndrome (SBDS) has been constantly breaking out in China since 2015. It is caused by a novel goose parvovirus-related virus (NGPV) and can severely restrict the growth of ducks. In this study, seven NGPV stains were isolated from different regions in China between 2015 and 2016. To better understand the correlation between NGPV and goose parvovirus (GPV), we conducted complete genome sequencing and a comprehensive analysis of the NGPV genome. The phylogenetic and alignment analysis showed that NGPV is a branch of GPV, sharing 92.2%-97.1% nucleotide identity with GPV. Compared with classical GPV, five consensus nucleotide mutations in all the seven NGPV isolates and two 14-nucleotide-pair deletions in six NGPV isolates were found in the inverted terminal repeats, twelve and eight synchronous amino acid changes were found in the replication protein and capsid protein of NGPV, respectively, which might be important for viral gene regulation, humoral immune responses, and host transfer. Notably, SDLY1602 was demonstrated a recombinant strain, with the potential major parent GPV vaccine strain 82-0321v and the minor parent GPV wild strain GDaGPV. This is the first report showing that the recombination between two classical GPV strains generated a NGPV strain circulating in nature. This study will advance our understanding of NGPV molecular biology and facilitate to elucidate the evolutionary characteristics of GPV.