發(fā)布時間：2018-01-31 18:26

  本文關鍵詞： 駱駝 斯氏副柔線蟲 角蠅 發(fā)育過程 18S rDNA　出處：《內(nèi)蒙古農(nóng)業(yè)大學》2015年碩士論文　論文類型：學位論文

【摘要】：駱駝斯氏副柔線蟲病(Parabronemosis)是山斯氏副柔線蟲(Parabronema skrjabini)寄生于駱駝真胃引起的一種嚴重危害養(yǎng)駝業(yè)的寄生性線蟲病,該病的傳播媒介為西方角蠅(Haematobia irritans)和截脈角蠅(Haematobia titillans)。為了弄清斯氏副柔線蟲在角蠅體內(nèi)的發(fā)育過程,本研究從駱駝生活環(huán)境的駝糞和牛糞中,大量收集疑似角蠅幼蟲,依據(jù)角蠅幼蟲齡期劃分標準,并通過分子生物學方法鑒定其為角蠅各齡期幼蟲；繼而大量剖解角蠅各齡期幼蟲,在其體內(nèi)尋找疑似斯氏副柔線蟲幼蟲,利用分子生物學方法對找到的疑似斯氏副柔線蟲幼蟲進行鑒定,統(tǒng)計角蠅各齡期幼蟲體內(nèi)斯氏副柔線蟲幼蟲的感染率并觀察其形態(tài)特征。與此同時,對內(nèi)蒙古地區(qū)西方角蠅和截脈角蠅18S rDNA基因全序列進行克隆和測定,比較兩種角蠅18S rDNA基因序列及其與GenBank中已登錄的9種雙翅目昆蟲18S rDNA基因序列的同源性,并利用它們的全序列和最保守同源區(qū)構(gòu)建系統(tǒng)進化樹,以確定兩種角蠅在雙翅目昆蟲中的位置,并為雙翅目不同科屬昆蟲之間的差異性及其分子系統(tǒng)進化特點的相關研究提供依據(jù)。結(jié)果表明：①從駱駝生活環(huán)境的駝糞和牛糞中收集的角蠅幼蟲被證實是角蠅各齡期幼蟲,通過分子生物學方法鑒定角蠅幼蟲時,改良酚/氯仿抽提法是提取角蠅各齡期幼蟲DNA的最佳方法。②角蠅感染斯氏副柔線蟲蟲卵始于其幼蟲階段,其Ⅰ、Ⅱ、Ⅲ期幼蟲均可感染,且平均感染率分別為4.48%、5.66%和4.78%。角蠅各齡期幼蟲體內(nèi)的斯氏副柔線蟲幼蟲在光學顯微鏡下的形態(tài)結(jié)構(gòu)相似,蟲體頭端鈍圓,口針明顯并位于其頂端；尾部尖細向腹面彎曲,肛門開口于蟲體近末端；其內(nèi)部結(jié)構(gòu)比較簡單,可以看到食道,且能分出食道肌質(zhì)部和腺質(zhì)部,腸與食道后端相連。③西方角蠅和截脈角蠅的18S rDNA基因全序列長度均為1984bp,二者的同源性為96.4%,存在73個識別位點,其中截脈角蠅的18S rDNA基因序列系國內(nèi)外首次報道。11種雙翅目昆蟲18S rDNA基因序列具有三段保守程度較高的同源區(qū),分別相當于西方角蠅18S rDNA基因序列的320bp～693bp、848bp～1181bp、1569bp～1849bp,其中第一段為最保守同源區(qū)；利用其構(gòu)建的系統(tǒng)發(fā)育樹對11種雙翅目昆蟲進行分類,比18SrDNA基因全序列構(gòu)建的系統(tǒng)發(fā)育樹更符合傳統(tǒng)形態(tài)學分類結(jié)果。本研究首次在角蠅各齡期幼蟲中分離鑒定出斯氏副柔線蟲幼蟲,并對其形態(tài)特征進行了描述,這不僅填補了國內(nèi)外對上述研究的空白,還為弄清斯氏副柔線蟲在傳播媒介角蠅體內(nèi)的發(fā)育過程奠定了基礎。
[Abstract]:Parabronema skrjabinii of Camel is Parabronema skrjabinii. Parasitic nematode parasitic disease caused by camel eurogastric disease that seriously endangers camel farming. The transmission vectors of the disease are Haematobia irritanss and Haematobia titillanss. In order to understand the developmental process of nematode skeldahl in hornfly. In this study, a large number of suspected hornfly larvae were collected from camel dung and cow dung in the living environment of camels. Then, a large number of larvae of different ages of hornfly were dissected, and the suspected larvae of Pararinus skrjabini were searched in its body, and the suspected larvae were identified by molecular biological method. The infection rate and morphological characteristics of nematode skeldahl larvae in different larvae of hornfly were analyzed. The 18s rDNA gene was cloned and sequenced from western keratflies and C. truncus in Inner Mongolia. To compare the 18s rDNA gene sequence of two species of hornfly and its homology with the 18s rDNA gene sequence of 9 species of Diptera insects registered in GenBank. The phylogenetic tree was constructed by using their whole sequence and most conserved homologous region to determine the position of two species of hornflies in Diptera insects. It also provides a basis for the study of the differences among different families and genera of Diptera and the characteristics of molecular phylogeny. The results show that:. 1 the larvae collected from camel dung and cow dung were proved to be larvae of different ages. The modified phenol / chloroform extraction method is the best method for extracting DNA from the larvae of keratflies by molecular biological method. Stage 鈪，

本文編號：1479706