猫泛白细胞减少症病毒临床毒株的分离鉴定OA

Feline panleukopenia is a highly contagious infectious disease that seriously endangers the health of felines,and its pathogen is feline panleukopenia virus.The purpose of this study was to isolate and iden-tify a strain of FPV and explore its pathogenicity.Collected clinical materials suspected of FPV infection were inoculated into Crandell Reese Feline Kidney(CRFK)cells.Obvious cytopathic effects occurred when CRFK cells were blindly passaged to the fourth generation.It was identified as FPV-positive by PCR and qPCR.Electron microscopy revealed a no envelope,20-25 nm diameter,spherical virus particle,which was consistent with the typical morphological characteristics of FPV.The isolated viral strain was named FPV-pA.Based on homology analysis and phylogenetic analysis of the FPV VP2 gene,it was found that the ho-mology between FPV-pA and FPV Cu-4 strain was 99.5％,and the homology with the matched strain was 98.0％-100％.The FPV-pA has a relatively close genetic relationship with FPV-QD22-8,FPLV-CC-19-02 and cat-1 strains.Based on genome-wide homology analysis and phylogenetic analysis,it was found that the homology between FPV-pA and FPV Cu-4 strain was 99.3％,and the homology with the matched strain was 97.5％-99.8％.The FPV-pA has a relatively close genetic relationship with FPV-QD22-8 strain.The TCID50 of the FPV-pA strain was 10-4.5CFU/mL.The results of animal challenge test showed that oral ad-ministration of 104.5 TCID50 the virus could cause typical symptoms of FPV infection in healthy three-month-old cats.In this study,a pathogenic clinical strain of FPV was successfully isolated and identified.It laid the foundation for the subsequent development of vaccines and clinical therapeutic drugs against feline panleukopenia.