School of Agricultural, Environmental and Veterinary Sciences, Faculty of Science and Health, Charles Sturt University, Wagga Wagga, NSW 2678, Australia.
Biosecurity Research Program and Training Centre, Gulbali Institute, Charles Sturt University, Wagga Wagga, NSW 2678, Australia.
Viruses. 2023 Sep 29;15(10):2025. doi: 10.3390/v15102025.
Pigeon circovirus (PiCV) is considered to be genetically diverse, with a relatively small circular single-stranded DNA genome of 2 kb that encodes for a capsid protein (Cap) and a replication initiator protein (Rep). Australasia is known to be the origin of diverse species of the Order Columbiformes, but limited data on the PiCV genome sequence has hindered phylogeographic studies in this species. To fill this gap, this study was conducted to investigate PiCV in 118 characteristic samples from different birds across Australia using PCR and sequencing. Eighteen partial PiCV sequences and one complete PiCV genome sequence were recovered from reservoir and aberrant hosts. Phylogenetic analyses revealed that PiCV circulating in Australia was scattered across three different subclades. Importantly, one subclade dominated within the PiCV sequenced from Australia and Poland, whereas other PiCV sequenced in this study were more closely related to the PiCV sequenced from China, USA and Japan. In addition, PiCV Rep sequences obtained from clinically affected plumed whistling duck, blue billed duck and Australian magpie demonstrated natural spillover of PiCV unveiled host generalist characteristics of the pigeon circovirus. These findings indicate that PiCV genomes circulating in Australia lack host adapted population structure but demonstrate natural spillover infection.
鸽圆环病毒（PiCV）被认为具有遗传多样性，其相对较小的环状单链 DNA 基因组为 2kb，编码衣壳蛋白（Cap）和复制起始蛋白（Rep）。澳大拉西亚已知是各种鸽形目物种的起源地，但该物种的 PiCV 基因组序列的有限数据阻碍了系统地理学研究。为了填补这一空白，本研究使用 PCR 和测序技术，对来自澳大利亚不同鸟类的 118 个特征样本中的 PiCV 进行了调查。从水库和异常宿主中回收了 18 个部分 PiCV 序列和一个完整的 PiCV 基因组序列。系统进化分析显示，在澳大利亚循环的 PiCV 分散在三个不同的亚群中。重要的是，一个亚群在澳大利亚和波兰测序的 PiCV 中占主导地位，而本研究中测序的其他 PiCV 与中国、美国和日本测序的 PiCV 更为密切相关。此外，从临床受影响的凤头潜鸭、蓝嘴鸭和澳大利亚喜鹊中获得的 PiCV Rep 序列揭示了 PiCV 的自然溢出，表现出鸽圆环病毒的宿主泛化特征。这些发现表明，在澳大利亚循环的 PiCV 基因组缺乏宿主适应的种群结构，但表现出自然溢出感染。
