The isolation and characterization of Duck astrovirus type‐1 remerging in China.

Since the first report from Cherry Valley ducks on a commercial duck farm in China (2008), duck astrovirus type 1(DAstV‐1)‐associated duck viral hepatitis (DVH) have been detected in several commercial duck flocks. A highly acute disease characterized by hepatitis broke out in ducklings in Shandong Province in March 2021, all diseased ducks have been immunized against the duck viral hepatitis vaccine. One DAstV‐1 strain, designated as DAstV‐SDWF, was isolated from a diseased duckling. Here, the isolation, cultivation, and characterization of DAstV‐1 isolate are described. The isolated astrovirus grew well in the LMH cell line. To determine the entire genomic of the DAstV‐SDWF isolate, the next‐generation sequencing (NGS) technique was conducted on the Illumina HiSeq platform. Complete genome sequence analysis revealed that DAstV‐SDWF isolate was 91.6%–98.6% homology with others DAstV‐1 deposited in Genbank. Similar clinical symptoms were successfully reproduced by an experimental infection study using the DAstV‐SDWF isolate. DAstV‐SDWF is the first DAstV‐1 strain whose experimental infection study has been conducted in China. Results of the above data demonstrated that DAstV‐1 could be one of the causative agents of the DVH occurring in China. The present works are likely to provide new insights into the pathogenicity and evolution of DAstV‐1 in ducks. [ABSTRACT FROM AUTHOR]