Conclusion
Our results demonstrated that Canadian PCV3 strains submitted to diagnostic laboratories and sequenced in this study were not diverse. All of the Canadian strains classified into PCV3a and segregated into different clusters with strains from North America, South America, Asia and Europe. Amino acid polymorphisms found in this study indicated the importance of these differences for understanding the evolutions of these strains. This is the first phylogenetic analysis of PCV3 strains among different provinces in Canada. The new PCV3 sequences will allow further investigations to explore the evolutions of PCV3 and future studies are required to better determine the polymorphisms in cap proteins could be associated with differences in the pathogenicity or antigenicity of PCV3 strains.