E-mail addresses:
E-mail: chenluhau@126.com (Lu Chen);yangyu7712@sina.com (Yurong
Yang)
Abstract: Here we described brain lesion in young captive lions
after exhibiting ataxia. The histopathological analyses of the brain
showed typical encephalitis with glial cell proliferation, neuronal
atrophy and necrosis, and encephalomalacia. We used a variety of
identification methods, including next-generation sequencing, polymerase
chain reaction (PCR), virus isolation, immunofluorescence staining
(IFA), and electron microscopy. Combined with clinical manifestations of
the infected cub, it determined that the dead cub have resulted from an
FPV embryonic infection. Through sequence analysis, it was found that
the infected virus may be a recombinant virus between FPV and CPV. this
study not only provides new gene sequences for the global study of
FPV-infected lions but also helps to further study the incidence and
genetic diversity of FPV.
KEYWORDS: Feline panleukopenia virus (FPV); young lions;
hypogranular cerebellar; brain lesion; embryonic infection
INTRODUCTION
Feline panleukopenia is caused by a feline panleukopenia virus (FPV),
which is a single-stranded DNA virus. Genetically, structurally, and
antigenically, FPV is closely related to the mink enteritis virus (MEV),
and canine parvovirus (CPV) (Truyen et al.,2013). FPV infections in
primarily domesticated cats and wild felids, including tigers (Panthera
Tigris) and lions (Panthera Leo)
(Driciru et al., 2006; Duarte et al., 2009; Goodrich et al.,2012), have
been described based on clinical, pathological, virologic, or molecular
data. Previous studies show that the symptoms associated with FPV
infection in tigers and lions are gastrointestinal enteritis and severe
hemorrhagic enteritis, respectively (Wang et al.,2019; Wang et al.,
2017); Evidence of neurological symptoms, such as ataxia, dysphagia, and
hydrocephalus, has not been described in lions infected with FPV
previously We, therefore describe previously undocumented
neuropathologic changes and molecular features associated with FPV
infection in lions.
In this study, we report an outbreak of fatal FPV infection among
captive lions in the Zhengzhou Zoo in central China. The survey results
showed that a total of 39 lion cubs were born between April 2017 to July
2019, and the cubs were of different ages and varying degrees of
clinical characteristics. Miscarriage in the early stage of pregnancy in
the lionesses resulted in 24 fetal deaths. Three cubs did not
breast-feed at birth and died within a week following birth. Another 12
normally born cubs were placed in similar or adjacent rooms. Signs of
limb weakness and walking instability began to appear at the age of 4-8
weeks. They were artificially fed with food and water, lost the ability
to act independently and had difficulty swallowing when they were about
a year old, and died of asphyxiation when eating meat. Besides, there
were no other obvious clinical manifestations. The histopathologic
findings, together with the sequencing analysis, virus isolations, PCR,
IFA and Electron microscopy observation results, suggest that parvovirus
was the cause of the death in these animals. This is the first time a
case of recombination of CPV and FPV infection that caused lion brain
tissue lesions and neurological symptoms has been found.
MATERIALS AND METHODS