This project is to develop an attenuated bivalent vaccine of waterfowl parvo and duck hepatitis viruses. We also wish that the high titer antibodies in colostrums would be transferred to ducklings and gosling from the vaccinated breeding ducks and geese for protection the baby animals from infection. So far, both strains of DHV1 and DHV1a have been passaged for 90 and 102 times in SPF chicken embryos, respectively. Duckings aged at 1-day old without maternal antibodies against DHV1 and DHV1a were inoculated by muscular and oral routes with the developing bivalent vaccine to test the safety, potency and virulence recovery. The result showed that the bivalent vaccine possessed high safety as well as no virulence for 1-day old duckling. In another trial, the tissue culture vaccine of waterfowl parvovirus was also developed to overcome the difficulty of the antibody free duck embryos. The virus titer in duck kidney cell reaches 10 x 7 TCID50/ml, which is higher than that in duck embryo fibroblast cells with titer of 10 x 3 TCID50/ml. However, a problem on the stability of the vial numbers for duck kidney cells will be resolved.