蒙古马马胃蝇三龄幼虫形态鉴定和种系发育关系分析  

Morphological Identification and Phylogenetic Analysis of Third-Instar Larvae of Gasterophilus pecorum in Mongolian Horses

作　　者：董俊斌[1] 包海泉[2] DONG Junbin;BAO Haiquan(College of Veterinary Medicine,Inner Mongolia Agricultural University,Key Laboratory of Clinical Diagnosis and Treatment Technology in Animal Disease,Ministry of Agriculture and Rural Affairs,Hohhot 010010,China;College of Food Science and Engineering,Inner Mongolia Agricultural University,Hohhot 010018,China)

机构地区：[1]内蒙古农业大学兽医学院农业农村部动物疾病临床诊疗技术重点实验室,内蒙古呼和浩特010010 [2]内蒙古农业大学食品科学与工程学院,内蒙古呼和浩特010018

出　　处：《中国兽医杂志》2025年第2期57-61,共5页Chinese Journal of Veterinary Medicine

基　　金：国家自然科学基金(32360884);内蒙古自治区自然科学基金(2024MS03079)。

摘　　要：为了明确内蒙古自治区呼和浩特市和通辽市蒙古马马胃蝇蛆病病原种类和种系发育关系,本试验于2023年3月在呼和浩特市和通辽市屠宰场采集马胃蝇三龄幼虫120只,利用光学显微镜和扫描电子显微镜对其进行形态学鉴定;通过PCR方法扩增其线粒体细胞色素氧化酶亚基Ⅰ(COXⅠ)基因,并利用MEGA 6.0和DnaSP 5.0软件将COXⅠ基因序列与GenBank中胃蝇科、皮蝇科和狂蝇科昆虫COXⅠ基因序列进行比对分析,并构建系统发育树;同时对呼和浩特市和通辽市的马胃蝇三龄幼虫进行线粒体COXⅠ基因单倍型和遗传分化分析。结果显示,本试验采集的马胃蝇三龄幼虫体色呈粉红色、口脊末端平滑,形态特征与黑腹胃蝇三龄幼虫一致。系统发育分析结果显示,通辽市黑腹胃蝇TONGLIAO1、TONGLIAO2、TONGLIAO3和TONGLIAO4与呼和浩特市黑腹胃蝇HUHEHAOTE2处于同一分支,呼和浩特市黑腹胃蝇HUHEHAOTE1与GenBank数据库中胃蝇科黑腹胃蝇处于同一分支,2个地区的黑腹胃蝇均与胃蝇科鼻胃蝇、红尾胃蝇和肠胃蝇处于不同分支,与皮蝇科、狂蝇科和外群双翅目麻蝇科距离较远。马胃蝇三龄幼虫COXⅠ基因相似性比对结果与系统发育分析结果一致。呼和浩特市和通辽市黑腹胃蝇线粒体COXⅠ基因序列共含有5个单倍型,二者没有共享单倍型,遗传分化系数(Fst)值大于0.05,基因流(Nm)为4。结果表明,呼和浩特市和通辽市蒙古马马胃蝇蛆病病原为黑腹胃蝇,且亲缘关系较近,未出现遗传分化。To clarify the pathogenic species and phylogenetic relationships of equine gastric myiasis in Mongolian horses from Hohhot and Tongliao in the Inner Mongolia Autonomous Region,this study collected 120 third-instar larvae of Gasterophilus from slaughterhouses in March 2023.Morphological identification was performed using optical and scanning electron microscopy.The mitochondrial cytochrome oxidase subunit I(COX I)gene was amplified via PCR,and MEGA 6.0 and DnaSP 5.0 software were used to compare the COX I gene sequences with those of Gasterophilidae,Hypodermatidae,and Oestridae from GenBank.Phylogenetic trees were constructed,and haplotype and genetic differentiation analyses were conducted for larvae from Hohhot and Tongliao.The results showed that the third-instar larvae collected had pink body coloration and smooth oral cristae,consistent with the morphological features of Gasterophilus pecorum.Phylogenetic analysis revealed that the Tongliao isolates TONGLIAO1,TONGLIAO2,TONGLIAO3,and TONGLIAO4 clustered in the same branch as Hohhot isolate HUHEHAOTE2.Hohhot isolate HUHEHAOTE1 grouped with other Gasterophilidae species in GenBank.Both regions'Gasterophilus pecorum isolates formed separate branches from Gasterophilus nasalis,Gasterophilus haemorrhoidalis,and Gasterophilus intestinalis and were distant from Hypodermatidae,Oestridae,and the outgroup Diptera(Sarcophagidae).Sequence similarity analyses of the COX I gene corroborated the phylogenetic findings.Five haplotypes were identified among the mitochondrial COX I gene sequences of Gasterophilus pecorum from Hohhot and Tongliao,with no shared haplotypes.The fixation index(Fst)was greater than 0.05,and the gene flow(Nm)was 4.The results indicate that the pathogen of equine gastric myiasis in Hohhot and Tongliao is Gasterophilus pecorum,with close phylogenetic relationships and no genetic differentiation.

关 键 词：蒙古马 黑腹胃蝇 形态学鉴定 发育树分析 

分 类 号：S852.7[农业科学—基础兽医学]