关键词: 猫1型疱疹病毒, 分离鉴定, 生物学特性分析, 高通量测序, 动物回归试验

Abstract:

This study aimed to obtain feline herpesivirus-1 (FHV-1) isolates from clinical samples through subculture and systematic identification, which laid the foundation for the study of FHV-1 vaccine. Ocular and nasal swabs of suspected FHV-1 infection cats were collected from pet hospitals. Crandell reese feline kidney (CRFK) were used to isolate virus, and evolutionary genetics analysis, ultrastructural observation via electron microscopy and animal regression test were performed on the isolates. The samples were isolated and sub cultured with CRFK cells, followed by identification as FHV-1 by PCR and immunofluorescence, and finally named as "FHV-ZH2202" strain. After the complete gene sequence of the virus was obtained by High-throughput sequencing and gene reference assembly, SNP analysis was conducted between the virus and domestic endemic strains. It was found that the non-synonymous mutant SNPS were mainly distributed in UL22 and US7 genes. Through phylogenetic analysis, FHV-ZH2202 and domestic endemic strains shared high homology in UL22 gene. However, US7 gene harbered by FHV-ZH2202 was with a relatively far relationship with the other domestic endemic strains. The results of animal regression test showed that all cats in infection groups were with typically clinical symptoms such as sneezing, ocular and nasal discharge. However, there was no death case in infection groups. Cats in the FHV-ZH2202 group shed viral DNA in ocular and nasal secretions to from the second day post infection (dpi) to 6-8 days post infection. One FHV-1 virus strain was successfully isolated and part of biological characteristics were analyzed. It was proved that FHV-ZH2202 strain had certain pathogenicity, which laid a foundation for the study of FHV-1 vaccine.

Key words: feline herpesvirus-1, isolation and identification, biological characteristics analysis, high-throughput sequencing, animal regression test