4Sambrook J,Frisch E F,Manniatis T.Molecular Cloning:A Laboratory Manual.3^rd ed[M].Cold Spring Harbor Laboratory Press,Cold Spring Harbor,NY.1989.
5Cornelia Büchen-Osmond.The universal virus database of the International Committee on Taxonomy of Viruses[DB].http://www.ncbi.nlm.nih.gov/ICTVdb,2005,2-18.
6Plummer P J,Alefantis T,Kaplan S,et al.Dectection of duck enteritis virus by polymerase Chian reaction[J].Avian Disease,1998,42:554-564.
7Lindberg A M,Johansson S.Phylogenetic analysis of Ljungan virus and A-2 plaque virus,new members of the Picornaviridae[J].Virus Res,2002,85 (1):61-70.
8Chomczynski P,Sacchi N.Single step method of RNA isolation by acid guanidinum thiocyanate phenol-chloroform extraction[J].Anal Biochem,1987,162:156-159.
9Levine P P,Fabricant J.A hitherto-undescribed virus disease of ducks in North America[J].Cornell Vet,1950,40(4):71-86.
10Asplin F D.Duck hepatitis:vaccination against two serological types[J].Vet Rec,1965,77(50):1529-1530.
8Ding C Y,Zhang D B. Molecular analysis of duck hepatitis virus type 1[J]. Virology,2007,361(1) :9-11.
9Kim M C, I.oh S J,et al. Molecular analysis of duck hepatitis vi- rus type I reveals a novel lineage close to the genus Parechovirus in the family Picornaviridae[J]. J Gen Virol, 2006,87:3307-3316.
10Kim M C,Kwon Y K,Joh S J,et al. Recent Korean isolates of duck hepatitis virus revea the presence of a new geno and sero- type when compared to duck hepatitis virus type 1 strains[J]. Arch Virol,2007,152(ll) :2059-2072.
