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Novel duck orthoreovirus can infect various hosts, mainly causing spleen necrosis and hemorrhagic necrotizing hepatitis, leading to immunosuppression and growth impairment. Infectious diseases characterized by swollen hock joints, movement disorders, and impaired growths have recently occurred in significant duck breeding areas in China. Infected ducks from Shandong Province were selected, and N-DRV-LY20 was isolated from the swollen joints. Next-generation sequencing (NGS) of N-DRV-LY20 and homology analysis showed that all ten fragments had the highest homology to N-DRV and the closest affinity to Duck/N-DRV-XT18/China/2018. After artificial inoculation with N-DRV-LY20 virus solution, Cherry Valley ducks showed the same symptoms of leg swelling and hock joint deformation, which were not explored in previous studies. A long history of evolution has led to significant variation in DRV and altered its pathogenicity. In this study, we confirmed the ability of N-DRV to cause viral arthritis in ducks and clarified this isolate's genetic characteristics and level of variation, providing a basis for the control and variation detection of N-DRV. [ABSTRACT FROM AUTHOR]

A severe infectious disease characterized with gout, haemorrhage and swellings of kidneys has affected goslings around the major goose‐producing regions in China since November 2016. A Novel goose‐origin astrovirus (AStV), designated as AStV/SDPY/Goose/1116/17 (AStV‐SDPY) strain, was isolated from diseased goslings, and experimental reproduction of gout was successful using the AStV‐SDPY strain. Additionally, the AStV‐SDPY was conducted for its full genome sequencing characterization using next‐generation sequencing (NGS) technique on Illumina HiSeq platform. A complete genome of the AStV‐SDPY was 7,252 nt in length and encoded three viral proteins. Phylogenetic analysis revealed that AStV‐SDPY strain belongs to an independent branch of avian astroviruses, and the nucleotide homology among AStV‐SDPY and other classic avian astrovirus strains was only 48.8%–68.2%. Results of above data indicated the causative agent of the gosling gout occurring in China is a novel divergent goose astrovirus. [ABSTRACT FROM AUTHOR]

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]

Since 2013, there have been an increasing number of cases of arthritis in broilers caused by avian orthoreovirus (ARV) in China, and the virus remains highly virulent in chicks with high‐level maternal antibodies. However, little information is available about the complete gene analysis and pathogenicity of the epidemic ARVs. In the study, the ARV strain (V‐ARV‐SD26) was isolated from broilers associated with arthritis in Shandong Province. To genetically characterize the ARV strain, the whole‐genome sequencing was conducted by next‐generation sequencing (NGS) technique. Sequence analysis demonstrated that V‐ARV‐SD26 might have acquired its current genomic composition through several homologous and, in case of the λC, μA and σB, divergent reassortment events. To further investigate the pathogenicity of the strain, 160 one‐day‐old Ross broilers with maternal antibodies were equally divided into four groups (foodpad‐, eye mucosa‐ and intramuscular‐inoculated groups and the negative control group), three experimental groups were inoculated separately with the low‐dose virus fluid, and the negative control was equally inoculated with sterile PBS. The results showed that the symptoms of broilers in foodpad inoculation group were the most serious, while that of the eye mucosa infection group were the mildest. Meanwhile, the cloacal cotton swabs and organs were collected for qRT‐PCR detection to evaluate the infection status. In conclusion, these findings indicate that V‐ARV‐SD26 is a divergent ARV strain, which provide experimental data for the prevention and control of newly emerged reovirus, and have a certain reference value for the preparation and evaluation of new vaccines. [ABSTRACT FROM AUTHOR]