Research And Biological Characterization Of A Duck Embryo Attenuated Strain Of Goose Parvovirus98E

Goose parvovirus infection also known as Gosling plague or Derzsy’s disease, mainly infects4-day-old to20-day-old domestic goslings and Muscovy duckings. The short course of the disease, rapid transmission, and a high mortality rate, causing serious economic losses, it’s one of the important infectious diseases of goose cultural industry. Ggosling plague was prevented mainly through immunizing goose with the GPV goose embryo/duck embryo attenuated vaccine and inactivated vaccine and then the gosling acquire antibody against the Gosling plague.This study used the cultivate goose parvovirus duck embryo attenuated strain GPV-98D15with continuously passaging in9day-old SPF duck embryo, identified the viral nucleic acid of the different generations by PCR and determine parts of biological characteristics during the generation process.The results of the biological characteristics of gosling plague duck embryo attenuated strains GPV-98D15showed that duck embryo could not die from Fl to F10, start gradually died from F11to F13.Beginning with F14, lethality rate of duck embryo keep stable at100%. The lethal time of duck embryo represent short regularly.The dead bodies of duck embryo were congested, and the locus of hemorrhage mainly concentrated in the head, neck, chest and legs, which are consistent with the feature of GPV pathological changes. It was successfully cloned the GPV-98D15strain NSlgene and VP1gene by PCR; The VP1gene of GPV-98D15strain and GPV-98E strain had partial nucleotide sequence mutation. The GPV-98D15strain attenuated stability and safety by duck embryo lethal dose, the pathogenicity test of goose embryo and safety test. GPV-98D15virus could infect duck embryo fibroblasts. It can be used duck embryo fibroblasts infected and half the amount of indirect immunofluorescence (IFA) to determination. We compared the immunogenicison of attenuated strains with the commercial vaccines SYG (41～50). Immuning20day-old goslings with GPV-98D15strain or SYG (41～50), antibody level rises ceaselessly, reached a peak at fifth weeks, and then decline slowly by ELISA, agar diffusion test and neutralization test. Antibody level of GPV-98D15immune group is slightly low compared with commercial vaccine SYG (41～50), but there is no significant difference (P>0.05). Detection of immune GPV-98D15strain to make small goose produces GPV specific neutralizing antibody by Neutralization test.The goslings acquired protective immunity. Therefore, the research provided a safe, effective, no season limitation of candidate strains, It always the material foundation For gosling plague virus attenuation mechanism research..