摘要
试验旨在了解2019年广西地区牛星状病毒(bovine astrovirus,BoAstV)在水牛群中的流行情况及毒株序列特征,并进行遗传进化分析。从2019年广西南宁、贵港、北海、横县、灵山5个地区15个水牛场共采集297份水牛粪便样品,使用Trizol法抽提样本总RNA后,利用半巢式RT-PCR方法对收集到的粪便样品进行检测,并将阳性样品连接到pMD18-T载体进行测序,对测序结果进行同源性分析及系统进化树构建。结果显示,BoAstV感染的水牛场阳性率为40.00%(6/15),样品总阳性率约为11.11%(33/297),1~180日龄犊牛感染率最高为18.75%(27/144);有19株BoAstV ORF1b基因测序成功,核苷酸序列同源性为53.9%~99.3%,氨基酸序列同源性为12.1%~98.5%。遗传进化分析发现,广西地区流行的BoAstV主要分为4个亚群:第一亚群是NNC-286、HX-3、HX-4和NNA-14,与新型的神经嗜性的牛星状病毒BoAstV NeuroS1和BoAstV BH89/14等Mamastrovirus 13亚群的序列之间有较高的亲缘性;第二亚群是NNA-12、NNA-13、NNA-17、NNA-11,与水牛星状病毒(buffalo astrovirus)亲缘性较近,属于水牛星状病毒分支内;第三亚群是HX-1、HX-5、HX-6和BH-C22,与经典的牛星状病毒毒株BoAstV B170-HK亲缘性较近;第四亚群包含NNA-7、NNA-15、NNA-6、NND-S2、NND-S16、NNC-296与BH-C14,与广西BoAstV地方流行毒株的亲缘性较近。不同基因型BoAstV感染了广西不同地区的水牛群体,本试验在广西地区发现了类神经嗜性BoAstV毒株感染水牛的情况,为进一步全面了解该病毒的流行病学和生物学特性提供参考。
This study was aimed to investigate the prevalence of bovine astrovirus(BoAstV)in buffalo from Guangxi,a total of 297 fecal samples were collected from 15 different scale buffalo farms in five regions including Nanning,Guigang,Beihai,Hengxian and Lingshan in Guangxi,the RNA was extracted by Trizol and the nest RT-PCR was used to detect the BoAstV.The positive samples were connected to pMD18-T vector for sequencing.Homology analysis of sequencing results was carried out,and phylogenetic tree was constructed.The results showed that the positive rate of BoAstV in buffalo farms was 40.00%(6/15),the positive rate of samples was 11.11%(33/297),and the buffalo calves which under 180 days old were more sensitve to infected BoAstV 18.75%(27/144).Total 19 BoAstV ORF1b sequences from positive samples were cloned and uploaded to NCBI BLAST.The nucleotide homology and amino acid sequence homology of the 19 BoAstV strains were 53.9%to 99.3%and 12.1%to 98.5%,respectively.Based on the phylogenetic analysis of these sequences and reference sequences,4 clusters could be classified.The first subgroup included NNC-286,HX-3,HX-4 and NNA-14,and these sequences were closed with novel nervous tropism BoAstV like BoAstV NeuroS1 and BoAstV BH89/14 which belonged with Mamastrovirus 13.The second subgroup included NNA-12,NNA-13,NNA-17 and NNA-11,and these sequences were closed with buffalo astrovirus,and belonged to the branch of buffalo astrovirus.The third subgroup included HX-1,HX-5,HX-6 and BH-C22,and these sequences were closed with classic BoAstV like BoAstV B170-HK.The last subgroup included NNA-7,NNA-15,NNA-6,NND-S2,NND-S16,NNC-296 and BH-C14,and these sequences were closely related to the local endemic strains of bovine stellavirus in Guangxi.The different genotype of BoAstV were infected buffalo herds in different regions from Guangxi.This study found that the neurophilic BoAstV strain infected buffalo in Guangxi,and provided reference for further understanding of the epidemiology and biological characteristics of the virus.
作者
李名洋
方庆励
黄伟坚
LI Mingyang;FANG Qingli;HUANG Weijian(College of Animal Science and Technology,Guangxi University,Nanning 530005,China)
出处
《中国畜牧兽医》
CAS
北大核心
2020年第9期2926-2934,共9页
China Animal Husbandry & Veterinary Medicine
基金
国家自然科学基金“猪星状病毒调控Ⅰ型干扰素反应的分子机制”(3176130094)。
