Phylogenetic analysis of porcine circovirus 3 (PCV3) circulating in
Canadian pigs
Abstract
Porcine circovirus 3 (PCV3) has been detected in pigs worldwide and
associated with several clinical signs. To investigate the genetic
diversity of PCV3 strains circulating in Canada, 44 PCV3 positive
samples from Saskatchewan (2/44), Manitoba (2/44), Quebec (4/44),
Alberta (11/44) and Ontario (25/44) submitted to diagnostic laboratories
in Canada between 2019 and 2021 were sequenced and analyzed.
Phylogenetic analysis of capsid genes showed that all of the 44 Canadian
strains classified into PCV3a and segregated into seven lineages with
common amino acid changes observed at A24V, R27K, N56D, T77S, Q98R,
L150I (F) and R168K positions. Future studies are required to determine
whether the polymorphisms in capsid proteins, as revealed in this study,
could be associated with differences in the pathogenicity or
antigenicity of PCV3 strains. This is the first phylogenetic analysis of
PCV3 strains among different provinces in Canada.