Molecular characteristics of a novel duck circovirus subtype 1d emerging in Anhui, China.

The frequency of infection of duck circovirus (DuCV) in Anhui province, China is not well-characterized. Therefore, in this study, we collected 69 samples from sick ducks and tested them for the presence of DuCV by conventional polymerase chain reaction (PCR) analysis. The complete viral genomes of five DuCV strains from five different cities were randomly selected, amplified via PCR, sequenced, and subjected to recombination analysis. The five DuCV genomes were named as AHAU9, AHAU25, AHAU28, AHAU37, and AHAUHQ. We found that 36.2 % of the ducks were infected with DuCV. The five DuCV strains had genome lengths ranging from 1987 to 1995 nucleotides, with a sequence similarity of 81.8-98.2 %. Among them, AHAU28, AHAU37, and AHAUHQ were closely related to the reference strain YF180403, GX1105 strain, and wd2015028 of DuCV, respectively. AHAU9 and AHAU25 were found to belong to a new DuCV subtype, DuCV-1d. Moreover, recombination analysis showed that the DuCV-1d subtype strains had the same recombination pattern. These results improve the understanding of the frequency of DuCV infection in Anhui province. Our findings may be useful for preventing and controlling the spread of DuCV.