Molecular Detection of Parvovirus in Captive Siberian Tigers and Lions in Northeastern China From 2019 to 2021

Abstract

The fact that wild felines are carriers of pernicious infectious viruses should be a major concern due to the potential cross-species transmission between the felines and human or domestic animals. However, studies on the virus in the captive wild felines, especially in tigers, are thin on the ground. In this study, we screened four infectious viruses, namely, feline parvovirus (FPV), feline coronavirus (FCoV), canine distemper virus (CDV), and influenza A virus (IAV), in the blood samples of 285 captive Siberian tigers (Panthera tigris altaica) and in the spleen samples of two deceased lions (Panthera leo), which were collected from 2019 to 2021 in three Siberian Tiger Parks from the northeast of China. Nucleic acids isolated from the blood samples collected from tigers and the spleen samples collected from two deceased lions were positive for FPV by PCR, and the positive rate was 4.6% (13/285) in tigers. Furthermore, the VP2 gene of FPV was amplified by nested PCR, and the sequences of the VP2 gene from these six FPV positive strains shared 98.3–99.9% homology with the reference. The key amino acid sites of VP2 protein were consistent with that of FPV reference strains. Phylogenetic analysis based on the VP2 gene showed that in this study, FPV-positive strains were grouped within the FPV clade and closely related to the Asian strains clade. The results of this study showed that FPV circulated in the captive Siberian tigers and lions in northeastern China and provided valuable information for the study of FPV epidemiology in wild felines. Therefore, we suggest that regular antibody monitoring and booster immunization for tigers should be performed.

Epidemiological and Molecular Approaches for a Fatal Feline Panleukopenia Virus Infection of Captive Siberian Tigers (Panthera tigris altaica) in the Republic of Korea

“…FPV, a member of the species Protoparvovirus carnivoran1 , is one of the fatal viral pathogens that can be cross-transmitted between domestic and wild carnivores, and FPV infection has been reported in various wild carnivores including Siberian tigers, threatening their survival [ 4 , 8 , 10 , 11 , 12 ]. In early May 2023, some Siberian tigers housed at Seoul Zoo showed clinical signs, such as depression, anorexia, vomiting, diarrhea, and epistaxis, and were suspected to be infected with a fatal enteric disease ( Figure 1 ).…”

“…Given that the qPCR assay used in this study was developed with the primers and probe set targeting the VP2 gene of all members of the Protoparvovirus carnivoran1 species including FPV, CPV-2, and its variants [ 13 ], further analyses were necessary to specify whether the detected virus was FPV or CPV-2. Indeed, previous reports have shown that tigers can be infected with genetically different parvoviruses, including FPV [ 8 , 10 , 11 , 25 ] and CPV-2a [ 4 , 26 ]. Therefore, to further characterize the detected KTPV-2305 strain, a complete VP2 gene sequence (GenBank accession number: OR365078) was obtained and analyzed in this study.…”

“…According to previous studies, the I101T mutation of FPV strains was first identified in a tiger parvovirus (CHJL-Siberian Tiger-01/2017 strain) isolated from a captive Siberian tiger in China [ 10 ] and was then further identified in other Siberian tigers in China [ 11 ] as well as dogs in Vietnam [ 35 ] and Italy [ 34 ]. The authors suggested that the I101T mutation was potentially unique in tiger- or dog-associated FPV strains.…”

“…Although captive tigers are bred in comfortable circumstances with ample food and without natural enemies, they are more vulnerable to FPV infections as they share habitats with domestic cats that are potential reservoirs of FPV. Indeed, fatal FPV infections have been reported in captive Siberian tigers throughout the world, including Portugal [ 8 ], Germany [ 4 ], China [ 10 , 11 ], and Korea [ 12 ]. To protect the endangered species from fatal FPV infections, more extensive epidemiological studies are required to explore the sources of infection and transmission routes of FPV to establish more advanced control strategies for FPV as well as other infectious pathogens.…”

Disease threats to tigers and their prey

“…The highly contagious, single-stranded DNA virus carnivore protoparvovirus 1 (hereafter parvovirus) can infect a wide range of carnivores and is divided into two main genogroups: the feline parvoviruses (formerly termed feline panleukopenia virus) and canine parvovirus 2 (CPV2) (Allison et al, 2013(Allison et al, , 2014. Both genogroups have been diagnosed in captive tigers (Steinel et al, 2000;Wang et al, 2019;Nur-Farahiyah et al, 2021;Huang et al, 2022), and CPV2 has been detected in tissues from a wild tiger in India (Shetty et al, 2020). The parvovirus genome is very small and lacks genes necessary for initiating viral replication, which is achieved through infection of rapidly dividing host cells (e.g., those found in developing fetuses or intestinal mucosa).…”