The current epidemic prevention of duck hepatitis viral disease is to inoculate ducklings with hyper-immune sera, but the passive immunization cost high and probably caused the spread of diseases and dispute for the anti-sera without any inspection and test by the national institute. Although there have live and inactivated vaccines for the vaccination of ducks and ducklings against waterfowl parvovirus, it is inconvenience since the parvovirus vaccine and duck hepatitis virus hyper-immune sera should be used separately. The project is trying to develop bivalent live or inactivated vaccines of waterfowl parvovirus and duck hepatitis virus for breeding ducks and geese so that ducklings and young geese can attained high levels of maternal antibodies against both diseases. It is also trying to find out the mutation condition and to choose a virus strain for vaccine production through the analysis of nucleic acid sequencing and cross protection test of duck hepatitis virus within 30 years. And it will evaluate the current vaccine strain and study the appropriate time of vaccination and opt the tissue culture for vaccine production instead of duck embryos that may containing waterfowl virus antibody.