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基于ITS序列的捻转血矛线虫系统进化分析 总被引：1，自引：1，他引：0
为分析捻转血矛线虫ITS序列的变异与虫株特性之间的关系,对捻转血矛线虫不同药物抗性虫株(苯并咪唑类药物抗性虫株、伊维菌素抗性虫株、莫西菌素抗性虫株、药物敏感虫株)、不同宿主来源虫株(长颈鹿、牛、绵羊、山羊、牦牛)和不同地理位置(中国、美国、意大利、法国、也门、马来西亚、澳大利亚)的分离株,以及毛圆科的其他线虫的ITS序列进行了分析。结果发现捻转血矛线虫与毛圆科其他线虫的ITS-2基因的相似性高,基于该基因建立的系统进化树可以很好地区分毛圆科不同属的线虫;捻转血矛线虫的抗药性特点与其ITS-1基因的变异进化关系不大;不同地理位置的捻转血矛线虫分离株的ITS-2基因变异很小;从野生动物长颈鹿体内分离的捻转血矛线虫的ITS-1基因与家养反刍动物分离株的差异较明显。研究结果表明捻转血矛线虫ITS序列在种内相对保守,不同虫株间变异较小,在毛圆科线虫的分子分类中具有一定意义。 相似文献
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为探究不同区域褐黄血蜱的基因变异情况及其遗传进化关系，试验以采集自湖南、河南省的20只褐黄血蜱为研究对象，通过PCR扩增其内转录间隔区Ⅱ（ITS-2）和烟酰胺脱氢酶亚基Ⅰ（nad1）基因序列，并对所获序列进行基因变异分析；在所获ITS-2和nad1基因序列的基础上，对不同地区褐黄血蜱的遗传进化关系进行分析，并利用ITS-2和nad1基因序列分别构建褐黄血蜱的系统进化树。结果显示，褐黄血蜱ITS-2基因序列长度均为1 160 bp，nad1基因序列长度均为285 bp；两省褐黄血蜱ITS-2及nad1基因的种内差异分别为0~1.9%和0~0.4%；湖南省褐黄血蜱的种内差异分别为0~1.4%和0~0.4%，而河南省的种内差异分别为0~1.2%和0~0.4%；两省褐黄血蜱ITS-2及nad1基因的种间差异分别为37.0%~52.0%和13.6%~24.8%。系统进化树结果显示，所有来自于两省的褐黄血蜱共处于同一分支上。结果表明，来自于两省的褐黄血蜱之间均存在基因变异的现象，但湖南省褐黄血蜱的基因变异程度和遗传多样性均高于河南省；两省褐黄血蜱之间的亲缘关系较近，暗示两省褐黄血蜱之间有基因交流，未出现遗传分化。 相似文献
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为了解新疆塔城及博乐地区羊捻转血矛线虫的流行情况和系统进化关系,以及这两个地区捻转血矛线虫对苯并咪唑类药物的抗药性,在塔城和博乐地区分别收集20、12个羊皱胃分离捻转血矛线虫,进行形态学鉴定、分子生物学鉴定以及抗药性分析。结果显示:在塔城地区的14个羊皱胃内发现有寄生性线虫,通过PCR鉴定出27只捻转血矛线虫;在博乐地区的7个羊皱胃内发现有寄生性线虫,共鉴定出55只捻转血矛线虫。对PCR阳性样品进行测序并应用最大似然法构建系统发育树进行系统进化分析发现:本试验所测序列与GenBank上的捻转血矛线虫虫株序列聚为一支,置信度为100%;与捻转血矛线虫同科不同属的环纹背带线虫虫株序列相聚类,置信度为100%;其外群为不同科、不同属的羊仰口线虫,登录号为KP792295.1;内群与外群分别形成独立的进化分支。对β-tubulin基因进行多序列比对发现,所选样本并未出现苯并咪唑类药物抗性。本研究有助于了解捻转血矛线虫流行情况,并为捻转血矛线虫系统进化及苯并咪唑类药物抗性分析提供了依据。 相似文献
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为更好地掌握我国部分地区羊胃肠道寄生虫病的流行情况以及捻转血矛线虫ZJ株近年来的系统进化关系,从而为捻转血矛线虫病的防治提供科学依据,于2014年9—12月采集了来自山东、吉林、黑龙江、内蒙古、辽宁、河北、江苏、天津和青海9个省(市)的490份羊粪样品,对其进行了寄生虫虫卵分类鉴定,对羊寄生虫病的流行病学特征进行总结分析;此外实验室于2004—2013年采集了来自浙江省嘉兴地区的15份捻转血矛线虫ZJ株成虫样品,设计特异性引物对样品ITS-2和ND4基因进行分子克隆测序鉴定比对,对该虫近10年来的系统进化进行分析。结果表明,全国各地羊体内肠道寄生虫的感染情况均较为严重,其中感染虫种的严重程度依次为原虫(83.27%)、线虫(64.29%)和绦虫(49.80%),感染相对最为严重的3个地区分别为天津、青海和内蒙古,而相对较轻的3个地区为江苏、黑龙江、山东。对捻转血矛线虫ZJ株的15份样品进行系统进化分析显示,ITS-2和ND4基因在10年间均有不同程度的遗传变异发生,变异范围分别为0.0%~3.9%和0.4%~4.8%,而ND4突变程度较大可能是由于虫种固有差异引起的。而2种基因都有部分位点突变后与H.placei(Haemonchus pacei)相同,说明嘉兴地区可能存在捻转血矛线虫和H.placei交叉感染的情况。调查分析结果将为制定更合理的羊寄生虫病防控方案提供参考依据,并为寄生虫系统进化分析研究奠定基础。 相似文献
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为鉴定绵阳地区山羊粪便中疑似血矛属线虫虫卵的虫种,本研究提取绵阳地区三个县山羊粪便中疑似血矛属线虫的虫卵DNA 60份,采用PCR技术扩增其核糖体第二内转录间隔区(rDNA ITS-2)基因序列,并与GenBank上公布的捻转血矛线虫同源序列进行比较分析。结果显示:60份疑似血矛属线虫的虫卵DNA样品均得到191bp的ITS-2片段;60条ITS-2序列共形成15条不同的序列,含有17个单变异位点,与GenBank中多株捻转血矛线虫的同源性达95.8%~100%;ML系统发育树显示,本研究得到的15种类型ITS-2序列与已报道的捻转血矛线虫(Haemonchus contortus)聚类形成一个分支。综上可得,60份来自山羊的血矛属线虫均为捻转血矛线虫。 相似文献
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《中国兽医杂志》2018,(9)
为了了解新疆伊犁地区捻转血矛线虫对苯并咪唑类药物的抗药性情况,本课题组对该地区某绵羊场捻转血矛线虫种群Ⅰ型β微管蛋白基因苯并咪唑抗药性相关单核苷酸多态性进行了调查。在通过捻转血矛线虫ITS-2种特异性PCR鉴定为捻转血矛线虫的基础上,分别扩增了27条捻转血矛线虫雄虫的Ⅰ型β微管蛋白基因,测序后对抗药性相关的167,198位点和200位点的单核苷酸多态性进行了调查研究。结果表明,该羊场的捻转血矛线虫种群的抗药性突变只发生在198位点和200位点,以198位点的抗药性突变为主,没有在167位点发现抗药性突变。共发现了4种基因型,198纯合敏感型及200位点纯合敏感型(20; 74. 07%)、198杂合抗药型及200位点纯合敏感型(3; 11. 11%)、198纯合敏感型及200位点杂合抗药型(2; 7. 41%)和198纯合抗药型及200位点纯合敏感型(2; 7. 41%)。该羊场捻转血矛线虫种群中存在198位点的纯合抗药型突变,说明有抗药性的风险,需要引起注意。本研究首次从分子水平报道了新疆伊犁地区捻转血矛线虫种群Ⅰ型β微管蛋白基因存在苯并咪唑抗药性突变,这对该地区以及其他类似地区的捻转血矛线虫病的防控以及抗药性的管理具有一定的指导意义。 相似文献
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为了解内蒙古地区捻转血矛线虫阿苯达唑耐药虫株Ⅰ型β微管蛋白基因单核苷酸多态性的情况,对来自内蒙古乌审旗、察右后旗和科右前旗3个地区各19条捻转血矛线虫雄虫进行ITS-2基因特异性PCR鉴定为捻转血矛线虫后,扩增出Ⅰ型β微管蛋白基因,测序后对耐药相关167、198和200位点突变情况进行调查分析。结果表明,在这3个地区均未发现167位点突变,主要是198和200位点发生突变,总体上看198位点突变频率高于200位点。分析这57条雄虫基因序列发现4种基因型,分别是198纯合耐药型及200纯合敏感型、198纯合敏感型及200纯合耐药型、198纯合敏感型及200杂合耐药型和198及200均杂合耐药型。而耐药基因型频率乌审旗为100%,察右后旗68.42%,科右前旗94.74%,这与粪便虫卵减少试验结果一致。研究结果为捻转血矛线虫病的预防和治疗提供一个新思路,可有效避免耐药性或者减缓耐药性的产生,减少畜牧养殖行业的经济损失。 相似文献
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长颈鹿血矛线虫ITS的PCR扩增与序列分析 总被引：3，自引：1，他引：3
目的利用分子生物学方法对来自长颈鹿皱胃的血矛线虫进行虫种鉴定。方法对样品XM9和XM11的核糖体DNA内转录间隔区(ITS-1、5.8 S、ITS-2)进行PCR扩增及序列分析,并与GenBank公布的血矛线虫(Hae-monchus)相应序列进行比较。结果来自长颈鹿皱胃的2条血矛线虫具有相同的ITS序列,5.8 S与ITS-1分别为153 bp、404 bp,与GenBank分布的捻转血矛线虫序列是一致的。ITS-2序列为231 bp,第753位是一个多态位点,该序列与来自国外的H.contortus,H.placei,H.longistipes存在0-18个碱基差异。结论来自长颈鹿的血矛线虫是捻转血矛线虫。 相似文献
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Multiple resistance to benzimidazoles (fenbendazole, albendazole and mebendazole) in a strain of Haemonchus contortus in sheep was detected on a farm where fenbendazole resistance had already been identified. Following a faecal egg count reduction test, this was confirmed by both critical and controlled anthelmintic tests. Different groups of sheep infected naturally or given an experimental infection with the fenbendazole-resistant strain were treated with the recommended doses of various anthelmintics. Compared to the control group, percentage reductions in faecal egg counts of sheep treated with fenbendazole, albendazole, mebendazole, levamisole and morantel varied between 56% and 81% and worm counts between 71% and 86%. The results indicate the presence of multiple anthelmintic resistance in this strain of H. contortus on this farm. Sheep treated with ivermectin and closantel showed 100% reductions in faecal egg and worm counts, suggesting high efficacy of these drugs against the population of H. contortus on this farm. 相似文献
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Gatongi PM Njoroge JM Scott ME Ranjan S Gathuma JM Munyua WK Cheruiyot H Prichard RK 《Veterinary parasitology》2003,110(3-4):235-240
Susceptibility to IVM (IVM) of “strain A” Haemonchus contortus which had been exposed to IVM four times over a 2-year period was compared to IVM susceptibility of “strain C” H. contortus which had no prior field exposure to IVM, by in vivo and in vitro methods. In vivo, the percentage reduction in faecal egg counts (FEC) and the total worm counts (TWC) were compared between control animals (lambs and kids) and animals treated with low dose IVM (20 μg/kg). In vitro susceptibility to IVM was evaluated by larval migration inhibition (LMI) after the two strains of H. contortus were exposed to different concentrations of IVM. The dose response, measured as the proportion of larvae inhibited from migrating, was used to estimate LD50. Although differences in response to IVM in the in vivo determinations were not significant, “strain A” H. contortus had a significantly higher LD50 than “strain C” in the LMI assay. Coincident with the conduct of the in vivo experiment, it was observed that “strain A” H. contortus established and survived better than “strain C” in the control lambs. 相似文献
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本研究采用双因素随机区组田间试验,研究了间作与施氮对柱花草（Stylosanthes guianensis）和扭黄茅（Heteropogon contortus）生物量、土壤氮磷吸收能力及柱花草/扭黄茅间作体系的土地当量比、种间相对竟争能力和相对拥剂系数的影响。结果表明,相同氮水平下,与柱花草单作比较,间作降低了柱花草对土壤氮磷的吸收,未施氮（N0）处理下氮磷的吸收量分别减少15.95%和12.86%,施氮（N120 kg·hm-2）处理下氮磷的吸收量分别减少41.98%和51.14%,抑制柱花草的生长,地上部生物量分别减幅9.69%（N0）和39.43%（N120）,地下部生物量分别减幅9.01%（N0）和53.21%（N120）。但间作提高了扭黄茅对土壤氮磷的吸收量,N0水平下氮磷的吸收量分别增加4.09%和10.62%,N120水平下氮磷的吸收量分别增加31.86%和39.78%,促进扭黄茅地上部的生长,N0和N120水平地上部生物量分别提高4.43%和24.98%。N0水平间作模式当量比均大于1,具有间作优势。相对柱花草,与扭黄茅间作的相对拥挤系数小于1,种间竞争能力小于0,为豆禾牧草的优化配置提供理论依据。 相似文献
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Eslami A Ranjbar-Bahadori S Zare R Razzaghi-Abyaneh M 《Veterinary parasitology》2005,130(3-4):263-266
One hundred compost samples were examined for the presence of nematophagous fungi on the sheep farms of Mazanderan, province, Iran. Arthrobotrys cladodes var. macroides (IRAN 677C = CBS 143565) was isolated from 3% of the samples examined. Nematophagous activity of this fungus which was shown for the first time in this study, revealed the addition of 1000, 8000, 20 000 and 100 000 conidia per gram of feces of sheep reduced significantly (P < 0.001) the number of Haemonchus contortus infective larvae in the feces by 41.71%, 63, 27%, 73.49% and 94.96%, respectively. These results show that A. cladodes var. macroides is a promising candidate for biological control of H. contortus. 相似文献
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Amphidial structure of ivermectin-resistant and susceptible laboratory and field strains of Haemonchus contortus 总被引：3，自引：0，他引：3
Freeman AS Nghiem C Li J Ashton FT Guerrero J Shoop WL Schad GA 《Veterinary parasitology》2003,110(3-4):217-226
The development of anthelmintic resistance by nematode parasites is a growing problem for veterinarians, pet owners, and producers. The intensive use of the macrocyclic lactones for the treatment of a variety of parasitic diseases has hastened the development of resistance to this family of parasiticides. As a result, resistance to ivermectin, moxidectin, nemadectin, and doramectin by Haemonchus contortus has been documented throughout the world.
Sensory neurons located in the cephalic end of nematodes are in close contact with the external environment. Through these neurons, important chemical and thermal cues are gathered by the parasite. Examination of serial electron micrographs of ivermectin-susceptible and ivermectin-resistant H. contortus allows for comparison of neuronal structure, arrangement of neurons within the amphidial channel, and distance of the tip of the dendritic processes to the amphidial pore. The latter of these characteristics provides a useful means by which to compare the association between the neurons and the external environment of the worm.
Comparison of parental laboratory strains of ivermectin-susceptible strains of H. contortus with related selected, ivermectin-resistant strains and with a wild-type ivermectin-susceptible field strain of H. contortus from Louisiana reveal that the ivermectin-resistant worms examined have markedly shorter sensory cilia than their ivermectin-susceptible parental counterparts. Additionally, the amphidial neurons of ivermectin-resistant worms are characterized by generalized degeneration and loss of detail, whereas other neurons outside of the channels, such as the labial and cephalic neurons, are normal in structure. These findings raise a number of questions regarding the relationship between amphidial structure and ivermectin resistance as well as the role of amphids as a means of entry for ivermectin. While shortened amphidial sensilla are associated with ivermectin resistance, it remains unclear if such a structural modification facilitates survival of nematodes exposed to macrocyclic lactones. 相似文献
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Four monoclonal antibodies (mAbs) (9.49, 24.27, 46.71 and 179.57) were produced against Fasciola hepatica excretory-secretory products. Isotype analysis revelead the antibodies to be IgM, IgG3, IgG1, and IgM. In immunoblot assays, the mAbs recognized different antigenic polypeptides migrating between 29 and 180 kDa. Specificity of the mAbs was evaluated by ELISA against antigens of Fascioloides magna, Anoplocephala magna, Stichorchis subtriquetrus, Haemonchus contortus, sheep liver extract (SLE), bovine liver extract (BLE), bovine serum albumin (BSA), bovine viral diarrhea virus (BVDV), and Madin-Darby bovine kidney (MDBK) cells. Monoclonals 9.49 and 24.27 were specific, and reacted only with Fasciola hepatica antigens. However, mAb 46.71 cross-reacted with antigens of Fascioloides magna, A. magna, Stichorchis subtriquetrus, and H. contortus but not with SLE, BLE, BSA, BVDV or MDBK cells. Monoclonal antibody 179.57 cross-reacted with Fascioloides magna, A. magna, S. subtriquetrus, H. contortus, SLE, and BLE, but not with BSA, BVDV, or MDBK cells. 相似文献
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本试验将从犬猫肠道中分离的钩棘单睾吸虫和扇棘单睾吸虫用盐酸卡红染色后观察其形态学特征;PCR扩增其ITS2基因序列并测序,并将测序结果与GenBank同属异形科的多棘单睾吸虫和横川后殖吸虫序列进行比对;应用Mega 6.05软件采用邻位相连法构建种系发育树进行分析。盐酸卡红染色后显示,钩棘单睾吸虫和扇棘单睾吸虫各形态学特征符合经典的分类学描述。PCR测序后获得钩棘单睾吸虫和扇棘单睾吸虫ITS2序列长度分别为295和297 bp,G+C含量分别为49.5%(146/295)和54.2%(161/297)。提交至GenBank后获得登录号分别为钩棘单睾吸虫KJ137221~KJ137223,KP165437~KP165439;扇棘单睾吸虫KP165440。序列比对结果显示,钩棘单睾吸虫和扇棘单睾吸虫种内差异性为0,4种异形吸虫种间差异为15.2%~28.9%。基于ITS2序列建立的种系发育树显示钩棘单睾吸虫和扇棘单睾吸虫构成自展值为78%的拓扑分支。 相似文献