Comparison of Immunogenicity of Egg Drop Syndrome Viruses HSH_(23) and AV127 Strains
JIANG Bei-yu et al(Institute of Animal Husbandry and Veterinary Medicine of Beijing Academy of Agriculture and Forestry Sciences,Beijing 100097)
[Objective] The aim was to compare the immune efficacy of the EDS76V HSH23 strain and the EDS76V AV127 strain.[Method]The triple inactivated vaccine of ND-IB-EDS(EDS76V HSH23 strain) produced in our laboratory,and the vaccine of ND-IB-EDS(EDS76V AV127 strain) sold on the market were used to immunize Hy-line brown commercial layers.The EDS HI titers of all immunized and control layers were detected,while 7 weeks after immunization,all layers were challenged by the EDS76V AV127 strain.[Result]The EDS HI level of all immunized layers significantly increased after immunization of 4 and 7 weeks,the titer of layers immunized with ours vaccine were 8.9 log2 and 8.05 log2,and that of layers immunized with vaccine sold in market was 7.6 log2 and 5.95 log2 respectively,while the titer of control layers was negative.After challenged,the layers of two immunized groups maintained laying rate above 90%,but the egg production rate of control layers drop to about 40%,moreover,the color of egg become light,and soft-shell egg,shell-less egg,rough-shell egg and abnormal egg appeared in the control layers.The laying rate of control hens recovered to 60% 26 days after challenge,and the laying rate was 75% in the period of 32 to 42 days,it did not recover to normal laying lever.Accounting the average egg of per layer in three groups in period of six weeks after challenge,the result indicated that the average egg of per layer immunized with our triple vaccine and immunized with vaccine sold in market as well as control layer was 39.48,38.41,26.60 respectively,so the average egg of per layer in immunized group increased 12 more than that of in control group.[Conclusion]The EDS76V HSH23 strain had good immunogenicity as well as EDS76V AV127 strain.
【CateGory Index】： S858.31