Cultivation of Inactivated Vaccine Strains of Porcine Epidemic Diarrhea Virus
In order to cultivate a vaccine strain of porcine epidemic diarrhea virus(PEDV)with weak virulence,high viral content and good immunogenicity,PEDV-YL strain was continuously passaged on Vero cells and purified by plaque cloning,followed by virulence test and immunogenicity test after determination of virus content.The results showed that,after F22 generation clone6 and clone7 strains were inoculated into healthy piglets,diarrhea was observed and PEDV was detected from all the experimental piglets,but no abnormalities were found in any organs after autopsy;the challenge protection rate was 60%,without any lesions in any organs.After F32 generation clone 10 and clone 12 strains were inoculated into healthy piglets,diarrhea was observed and PEDV was detected from 60%piglets,and no obvious changes were observed in all organs after autopsy;the challenge protection rate of the group with primary vaccination was from 60%to 80%,and that with secondary vaccination was 100%,without any lesions in any organs.The virus content of F32 generation clone10 strain was slightly lower than that of clone12 strain,which were with comparable immunogenicity.In conclusion,F32 generation clone 12 strain was more suitable as a candidate for vaccine development,with better effect of secondary vaccination.The development of porcine epidemic diarrhea inactivated vaccines was technically supported by the study.
PEDVcultivationvirus contentvirulence testimmunogenicity test