J Vet Sci.  2023 Mar;24(2):e29. 10.4142/jvs.22197.

Isolation of feline panleukopenia virus from Yanji of China and molecular epidemiology from 2021 to 2022

• Xue H
• Hu C
• Ma H
• Song Y
• Zhu K
• Fu J
• Mu B
• Gao X

• KMID: 2541336
• DOI: http://doi.org/10.4142/jvs.22197

Abstract

Background
Feline panleukopenia virus (FPV) is a widespread and highly infectious pathogen in cats with a high mortality rate. Although Yanji has a developed cat breeding industry, the variation of FPV locally is still unclear.
Objectives
This study aimed to isolate and investigate the epidemiology of FPV in Yanji between 2021 and 2022.
Methods
A strain of FPV was isolated from F81 cells. Cats suspected of FPV infection (n = 80) between 2021 and 2022 from Yanji were enrolled in this study. The capsid protein 2 (VP2) of FPV was amplified. It was cloned into the pMD-19T vector and transformed into a competent Escherichia coli strain. The positive colonies were analyzed via VP2 Sanger sequencing. A phylogenetic analysis based on a VP2 coding sequence was performed to identify the genetic relationships between the strains.
Results
An FPV strain named YBYJ-1 was successfully isolated. The virus diameter was approximately 20–24 nm, 50% tissue culture infectious dose = 1 × 10 ^−4.94 /mL, which caused cytopathic effect in F81 cells. The epidemiological survey from 2021 to 2022 showed that 27 of the 80 samples were FPV-positive. Additionally, three strains positive for CPV-2c were unexpectedly found. Phylogenetic analysis showed that most of the 27 FPV strains belonged to the same group, and no mutations were found in the critical amino acids.
Conclusions
A local FPV strain named YBYJ-1 was successfully isolated. There was no critical mutation in FPV in Yanji, but some cases with CPV-2c infected cats were identified.

Keyword

Cats; capsid protein; PCR; mutation; sequence analysis