Preliminary Research And Establishment Of National Standards Of Classical Swine Fever Lapinised Vaccine

Classical swine fever(CSF),caused by Classical swine fever virus,is a highly contagious disease of Pigs,and one of OIE listed infectious disease.Classical swine fever is presently one of the most harmful pig diseases with wildly epidemic.In resent years,the first choice for veterinarian to control these diseases was always Classical swine fever vaccine.We urgent need to develop and apply the national standards of Classical Swine Fever lapinised vaccine which will contribute to standardize the production and sales of vaccine in market.Using qualified lapinised vaccine of Classical Swine Fever virus as candidates,screening,analyzing and measuring the characteristic value,we developed national standards of lapinised vaccine to Calibrate the quality of the lapinised vaccine of Classical Swine Fever virus.In this research,according to developed screening method and characteristic value,national standards of lapinised vaccine were applied to the market after screening and collaborative study,which would not only lined with international practice,but also filled up marketing blank space.Using qualified lapinised vaccine of Classical Swine Fever virus as candidates,measuring the characteristic value of standard substance according to regulation of Veterinary Biologics,the new certification methods were developed and compared with traditional methods.The characteristic value of candidates were measured by Physical Properties,content,moisture,efficacy test, concentration,which were established the program of national standard substance after collaborative study.By the research of the standard substance,comparison with traditional method,we introduced a real-time quantitative RT-PCR method.The results indicated that sensitivity of this assay was 69 copies/μL.The assay was linear within 6-log dynamic rang.Using this assay,we standardized ten different candidates of standard substance selected,the results showed that positive rate was 100% and candidates had stable Ct value and good homogeneity.By using the assay,two batches of candidates(83081225,2009011)were screened.The results showed that the Physical Properties of 2009011 is pink sponginess puff mass,which can easily separate from the wall of bottles and quickly dissolved after adding diluents.The weights are between 0.16～0.19 g,the average is 0.1792 g.The CV is 2.00%.The water remaining volume is less than or equal to 4%.The efficacy is 1/450.The content is more than 8.35×10~5 copies/mL.The candidate numbering 2009011 meet the development requirement of standard substance,which can be used as candidates for collaborative study.In addition,traditional method and new method can mutual cooperation to screen the standard substance.The method not only fulfilled the development of national standard substance which will standardize the production vaccine,but also assisted traditional method to evaluate lapinised vaccine of Classical Swine Fever virus,Pathogenesis of CSFV and the utilization of standard substance.