自2011年以来,Gyrovirusgalga1(GyVg1,以前被认为是禽陀螺病毒2)株已在全球范围内被广泛检测到。然而,由于没有最新的报告检查中国南方羊群中GyVg1的分布,这种病毒的流行病学是未知的。为了调查GyVg1的流行和遗传进化,在2020年至2022年期间,从中国南方6个省的113个养鸡场收集了总共2077个田间样本。其中,315个样本(315/2,077,15.17%)通过PCR检测为GyVg1阳性。中国南方不同地区之间的GyVg1检测阳性率为11.69%(广东)至22.46%(云南)。分析GyVg1患病率与样本来源组的相关性,结果表明,在内脏组织中观察到GyVg1的血清阳性率最高(27.34%,187/684),显著高于(P<0.05)羽毛轴(17.22%,31/180),血清(8.85%,78/881),和粪便(5.72%,19/332)。此外,对10个GyVg1菌株的完整基因组进行了测序和分析,显示96.2至99.9%的核苷酸同一性,97.0至100.0%,95.2至100.0%,在整个基因组中占95.7%至99.8%,ORF1、ORF2和ORF3,和94.4至100.0%,91.3至100.0%,在VP2,VP3和VP1蛋白中,氨基酸相似性为98.7%至100.0%,分别。全基因组系统发育分析表明,10株GyVg1属于基因型I,一个菌株属于基因型III。序列分析显示在VP1、VP2和VP3蛋白中均有几个氨基酸取代。我们的结果增强了对中国南方地区GyVg1感染的分子特征的理解。总之,这项研究揭示了中国鸡GyVg1的高流行和高遗传分化,并表明GyVg1对养鸡业的潜在影响可能令人担忧。
Since 2011, the Gyrovirus galga 1 (GyVg1, previously recognized as avian gyrovirus 2) strain has extensively been detected worldwide. However, because there are no up-to-date reports of examining the distribution of GyVg1 in flocks in southern China, the epidemiology of this virus is unknown. To investigate the prevalence and genetic evolution of GyVg1, a total of 2,077 field samples collected from 113 chicken farms in 6 provinces in southern China during 2020 to 2022 were tested. Among them, 315 samples (315/2,077, 15.17%) were positive for GyVg1 by PCR. The positive rate of GyVg1 detection between different regions of southern China ranged from 11.69% (Guangdong) to 22.46% (Yunnan). The correlation between GyVg1 prevalence and sample source groups was analyzed, the results showing that the highest seroprevalence of GyVg1 was observed in visceral tissues (27.34%, 187/684), significantly higher (P < 0.05) than that of feather shafts (17.22%, 31/180), serums (8.85%, 78/881), and fecal (5.72%, 19/332). Additionally, the complete genomes of 10 GyVg1 strains were sequenced and analyzed, which showed nucleotide identities of 96.2 to 99.9%, 97.0 to 100.0%, 95.2 to 100.0%, and 95.7 to 99.8% in the complete genome, ORF1, ORF2, and ORF3, respectively, and 94.4 to 100.0%, 91.3 to 100.0%, and 98.7 to 100.0% amino acid similarity in the VP2, VP3, and VP1 proteins, respectively. Phylogenetic analysis of the whole genome showed that 10 GyVg1 strains belong to genotype I, and one strain belongs to genotype III. Sequence analysis showed several amino acid substitutions in both the VP1, VP2, and VP3 proteins. Our results enhance the understanding of the molecular characterization of GyVg1 infection in southern China. In conclusion, this study reveals the high prevalence and high genetic differentiation of GyVg1 in Chinese chickens and suggests that the potential impact of GyVg1 on the chicken industry may be of concern.