Département de Microbiologie-Infectiologie et d'Immunologie, Université Laval, Québec City, Québec, Canada.
Department of Biochemistry, Microbiology and Bioinformatics, Université Laval, Québec City, Québec, Canada.
Res Vet Sci. 2021 Jan;134:171-180. doi: 10.1016/j.rvsc.2020.12.010. Epub 2020 Dec 22.
Emerging viral diseases include pathogens that can threaten the health of the Canadian swineherd. Anelloviruses and Circoviruses comprise of pathogens with veterinary significance. The aim of this study was to determine the genomic organization and phylogenetic relationships of Torque teno sus virus (TTsusV) and Porcine circovirus (PCV) from Canadian pig samples. Fecal and tissue specimens were collected during the winter, spring and summer of 2018. We utilized either virus- or genus-specific PCR assays to characterize the occurrence and genetic diversity of TTsusV and PCV in Canadian pigs. Pairwise comparison of all partial sequences and identity calculation was performed using MAFFT algorithm implemented in Sequence Demarcation Tool (SDT). The obtained full-length sequences were aligned using ClustalW, and phylogeny was inferred using a Maximum likelihood (ML) method by Geneious software. The PCR detection results revealed that the overall positive rate of TTsusV type-1 and type-2 was 45.6% and 32.6%, respectively. The TTsusV isolate MK990454 from Canada clustered in the subtype TTsusV1b, while the TTsusV isolate MK872392 fell in the subtype TTsusV2c, and all showed similarity to known American and Chinese isolates. In addition, our screening PCR showed that 2.7% of stool samples were positive for PCV1. Phylogenetic analysis using the full-length sequence demonstrated that PCV1 (MK872393) isolated from Quebec clustered with other Chinese PCV1 strains. Despite the far geographical distance between Canada and China, the close similarity between Canadian and Chinese TTsusV1 and 2, and PCV1 sequences may be explained by a considerable amount of pig trade between these two nations.
新发病毒性疾病包括可能威胁加拿大养猪业健康的病原体。细小病毒属和圆环病毒属包括具有兽医重要性的病原体。本研究旨在确定来自加拿大猪样本的 Torque teno sus 病毒（TTsusV）和猪圆环病毒（PCV）的基因组组织和系统发育关系。在 2018 年冬季、春季和夏季采集粪便和组织标本。我们利用病毒或属特异性 PCR 检测来描述加拿大猪中 TTsusV 和 PCV 的发生和遗传多样性。使用 MAFFT 算法在 Sequence Demarcation Tool（SDT）中进行所有部分序列的成对比较和身份计算。使用 ClustalW 对齐获得的全长序列，并使用 Geneious 软件通过最大似然（ML）方法推断系统发育。PCR 检测结果显示，TTsusV 型 1 和型 2 的总阳性率分别为 45.6%和 32.6%。来自加拿大的 TTsusV 分离株 MK990454 聚类在 TTsusV1b 亚群中，而 TTsusV 分离株 MK872392 属于 TTsusV2c 亚群，与已知的美洲和中国分离株具有相似性。此外，我们的筛选 PCR 显示，2.7%的粪便样本 PCV1 呈阳性。使用全长序列进行的系统发育分析表明，来自魁北克的 PCV1（MK872393）与其他中国 PCV1 株聚类。尽管加拿大和中国之间的地理距离遥远，但加拿大和中国的 TTsusV1 和 2 以及 PCV1 序列非常相似，这可能是由于这两个国家之间有大量的猪贸易。
