| dc.description.abstract | Background: The Eurasian beaver (Castor fiber), the largest rodent on the Eurasian continent, is considered a native species in Hungary. It faced extinction
due to overhunting in 1865 but was successfully reintroduced in the subsequent
years through migration and deliberate repopulation efforts. The population
grew steadily, resulting in an estimated 8,500 individuals in 2019. Despite these
developments, the viral presence in the growing beaver population has not been
extensively studied.
Objectives: This study aimed to assess the presence of polyomaviruses (PyVs)
in the native Hungarian beaver population, to identify and characterize novel PyVs
that can be detected in these mammals.
Materials and Methods: Molecular analysis was applied to investigate the
presence of PyVs in two Eurasian beavers that died in Hungary in 2019. From the
specimens, liver, spleen and kidney tissues were sampled. A nested PCR was used
to amplify a conserved region of the major capsid protein-encoding VP1 gene.
Short DNA amplicons were sequenced using the Sanger method. Phylogenetic
tree was calculated by Maximum Likelihood estimation, using PhyML software,
based on VP1 amino acid sequences.
Results and Discussion: An unknown PyV was detected in both beaver samples tested, the first identification of PyV in beavers globally. The detected virus is
recommended to be named as Castor fiber polyomavirus 1, and it is likely represents
the first member of a new PyV species. Phylogenetic analysis revealed that this
new PyV belongs to the genus Alphapolyomavirus and forms a distinct clade with
PyVs from different shrew species. This clade is clearly separate from other rodent
PyVs, indicating a unique evolutionary history. However, the exact relationship and
potential impact of this PyV on beaver health remain uncertain. Given the potential
of PyVs to act as facultative pathogens under specific conditions, further research
is needed to determine the extent of their role in beaver viral diseases. | en_US |
