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猪食道口线虫ITS—1和ITS-2rDNA的PCR—SSCP分析 总被引：4，自引：0，他引：4
以采自我国不同地区猪体的食道口线虫虫株为研究对象，PCR扩增出ITS-1和ITS-2序列片段，然后采用单链构象多态性（SSCP）方法分析PCR产物，对不同地区食道口线虫进行分子鉴定。所有样品经SSCP分析显示两种带型，第一种为有齿食道口线虫带型，另一种为未定种食道口线虫带型。代表性样品的测序结果表明，未定种食道口线虫带型的样品为四棘食道口线虫。本研究在国际上首次报道了中国猪四棘食道口线虫的ITS序列，并建立了区分有齿食道口线虫和四棘食道口线虫的PCR-SSCP方法，从而为食道口线虫的分子生物学的进一步研究奠定了基础。 相似文献
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片形吸虫第一内转录间隔区DNA多态性的研究 总被引：9，自引：0，他引：9
以不同地区的片形吸虫虫株为研究对象，经PCR扩增出了ITS-1部分基因片段，采用单链构象多态性(SSCP)方法，并结合序列分析研究了不同地区片形吸虫ITS-1 DNA的多态性。不同地区的样品经SSCP分析，显示3种带型，第1种为大片形吸虫的带型，第2种为肝片形吸虫的带型，第3种为2种带形的混合带型。广西区样品和大部分贵州省样品属于大片形吸虫带型；四川省、黑龙江省和部分贵州省样品为混合带型；南京市和甘肃省样品为肝片形吸虫带型或混合带型。测序结果表明，根据ITS-1基因的序列变异位点可区分2种片形吸虫；表现为混合带型的样品在变异位点具有多态性。本研究结果显示，ITS-1片段可作为遗传标记用以区分大片形吸虫和肝片形吸虫，同时也证实，在我国除了这2种片形吸虫外，还可能存在着“中间型”的片形吸虫。 相似文献
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《畜牧兽医科技信息》2020,(8)
正食道口线虫病是由毛线科的食道口线虫引起的。寄生在猪体内的食道口线虫,目前发现的有三种,即有齿食道口线虫、长尾食道口线虫、熊氏食道口线虫。由于食道口线虫寄生在猪的大肠里,它们的幼虫寄生在大肠肠壁里,使肠壁发生结节病变。因此,本病也称为结节虫病。1病原1.1有齿食道口线虫头囊膨大,无侧翼膜,食道漏斗小,颈乳突位于食道膨大部的两侧。口囊浅,囊壁平直。雄虫体长8～9mm,交合刺长1.0～1.14mm。雌虫体长8～11.3mm,阴门在肛门前方0.208～0.388mm,阴唇稍隆起,阴唇向前,长0.10～0.15mm。 相似文献
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蛇四棘食道口线虫线粒体cox1 基因的克隆及序列分析 总被引：1，自引：1，他引：0
本研究旨在分析长沙市四棘食道口线虫分离株线粒体细胞色素c氧化酶第Ⅰ亚基(cox1)基因部分序列(pcox1)的遗传变异情况。应用聚合酶链反应(PCR)扩增四棘食道口线虫虫株的pcox1,应用Clustal X 1.83程序对序列进行比对,同时利用DNAStar 5.0中的MegAlign程序进行同源性分析,并与GenBankTM中已知四棘食道口线虫相应基因序列进行比较分析。所得pcox1序列长度一致,均为393 bp,与GenBank公布的线虫相关序列进行比较分析结果表明,各个分离株与已知四棘食道口线虫相应基因的相似性分别在98%以上,与其它科线虫的相似性均小于91%。四棘食道口线虫pcox1序列种内相对保守,种间差异明显。本研究为进一步研究四棘食道口线虫的群体遗传学奠定了基础。 相似文献
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以采自我国不同地区的片形吸虫虫体为研究对象，PCR扩增出核糖体DNA (rDNA)的第一内转录间隔区(ITS-1)序列，然后采用非同位素的单链构象多态性(Cold-SSCP)方法分析PCR产物，对不同地区片形吸虫进行分子鉴定。所有样品经Cold-SSCP分析显示2种带型。样品测序及序列分析结果表明，第1种为肝片形吸虫带型，另1种为大片形吸虫带型。本研究建立了区分大片形吸虫和肝片形吸虫的Cold SSCP方法，可用于这2种吸虫的分子流行病学调查，从而为片形吸虫分子生物学的进一步研究奠定了基础。 相似文献
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PCR-SSCP对我国鲁道夫对盲囊线虫的分子鉴定 总被引：1，自引：0，他引：1
对来自青海湖的鲁道夫对盲囊线虫（Contracaecum rudolphii）核糖体DNA第一、第二内转录间隔区（ITS-1、ITS-2）进行PCR扩增、DNA单链构象多态性（SSCP）分析及序列分析。并与来自欧洲的2个姊妹种鲁道夫对盲囊线虫进行了比较。结果显示，我国青海湖的鲁道夫对盲囊线虫与来自意大利的（.rudolphii B具有一样的SSCP带型及ITS序列，但不同于C．rudolphiiA．因此属于C.rudolphii B。本试验证实了ITS片段可作为遗传标记用于鉴别鲁道夫对盲囊线虫的姊妹种，从而为鲁道夫对盲囊线虫的进一步研究奠定了基础。 相似文献
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1990～1993年,丹寨县对畜禽寄生虫病进行区系普查,并且在长期的肉品检疫工作中,我们发现本病在我县流行普遍,情况严重。1方法用粪便漂浮法检查粪便中有无虫卵,剖解肠道采集虫体,镜检,并观察宿主临床症状和肠病理变化。2调查结果2.1虫种本病为夏伯特科(Chabertidae)食道口属(Esophagostomum)的多种线虫寄生于猪的结肠所引起,有些种的幼虫在大肠内壁形成结节,故又称结节虫。常见于我县猪的食道口线虫有以下3种:有齿食道口线虫,虫体呈乳白色,寄生于结肠;长尾食道口线虫,虫体呈暗灰色,寄生于盲肠和结肠;短尾食道口线虫,寄生于结肠。2.2流行情况… 相似文献
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This study was undertaken to determine the level of resistance against pyrantel citrate in strains of Oesophagostomum quadrispinulatum and Oesophagostomum dentatum which have previously been found resistant to this anthelmintic. Groups of pigs were artificially infected with batches of infective larvae which were previously found either susceptible or resistant to pyrantel citrate. After treatment with 1, 2 and 4 times the recommended dose (14 mg kg-1) of pyrantel citrate, the resistant O. quadrispinulatum population was reduced by 51.0, 76.2 and 86.1%, and O. dentatum by 41.2, 47.9 and 78.5%. The results indicated that O. dentatum was slightly more resistant (P less than 0.05) than O. quadrispinulatum to pyrantel citrate. Treatment of the susceptible worms with 1 and 2 times the recommended dose caused a reduction in worm numbers by 61.0 and 99.4%, respectively. 相似文献
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安氏隐孢子虫ITS-1序列的PCR扩增、克隆及分析 总被引：1，自引：0，他引：1
通过对国内三株安氏隐孢子虫(Cryptosporidium andersoni)即GD株、HN株和AH株的rDNA的内转录间隔区Ⅰ(ITS_1)序列进行PCR扩增、克隆、测序和序列分析,旨在确定ITS_1是否可作为C.andersoni分子分类的遗传标记。结果表明:GD株、HN株和AH株的ITS_1序列基本一致,仅AH株有三个碱基的差异;但与GenBank注册的C.muris和C.parvum存在种间差异,而且差异显著。说明ITS_1可作为C.andersoni种的遗传标记,从而为隐孢子虫属的种间鉴定以及进一步的分子流行病学调查和分子诊断学研究奠定了基础。 相似文献
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Two strains of Oesophagostomum spp., consisting of both O. quadrispinulatum and O. dentatum, were subjected to a controlled in vivo assay for resistance to levamisole and pyrantel by comparison with susceptible isolates. One strain (LEM) was recently isolated from a commercial herd, where sows showed high numbers of strongyle eggs in faeces within 2 weeks of farrowing and following treatment with levamisole at the manufacturer's recommended dose rate 1 week before farrowing. Levamisole had been used as the sole anthelmintic for treatment for at least 7 years on this farm. Treatment with pyrantel in this herd also indicated cross-resistance to this drug. A mixed population of O. quadrispinulatum and O. dentatum of this strain was subjected to controlled in vivo assays. Faecal egg count reduction (FECR) was found to be -573.3% (P greater than 0.05) and worm count reductions (WCR) of O. quadrispinulatum and O. dentatum were estimated as 44.5% (P greater than 0.05) and 96.4% (P less than 0.001), respectively. Treatment with pyrantel showed that cross-resistance existed to this drug, with FECR of 10.4% (P greater than 0.05) and WCR of 64.5% (P greater than 0.05) and 90.7% (P less than 0.05) for O. quadrispinulatum and O. dentatum, respectively. Another strain (VJ) was isolated from another commercial pig herd, which was dosed with pyrantel citrate four times a year for at least 8 years. This strain showed resistance to pyrantel, with FECR of 43.8% (P greater than 0.05) and WCR of 65.9% (P greater than 0.05) and 49.4% (P greater than 0.05) for O. quadrispinulatum and O. dentatum, respectively. However, both species were susceptible to levamisole. Our results suggested that selection with levamisole gave rise to levamisole resistance and automatically conferred resistance to pyrantel, whereas selection with pyrantel only resulted in resistance to this drug alone. These findings are discussed in relation to the location of the two species of Oesophagostomum in the large intestine of pigs and the mode of action of this class of anthelmintics. 相似文献
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Forty pigs with induced infections of Ascaris suum, Trichuris suis, Metastrongylus spp., Oesophagostomum dentatum and O. quadrispinulatum were assigned to five-dose groups of moxidectin 0.5% pour-on with eight pigs per dose group. The doses were: moxidectin, 0 (vehicle control), 0.75, 1.00, 1.25, and 1.50 mg/kg(-1) body weight. Worm egg counts (EPG) were made from fecal samples collected on Day 2 pretreatment and on Day 14 or 15 post-treatment. Animals were ranked according to the descending order of A. suum egg counts made on Day 2 and blocked in groups of five. Pigs in blocked groups were assigned randomly to each of the five dose groups. Treatment doses were calculated on the basis of weights taken on Day 1 and were administered topically from the neck to the base of the tail. Pigs were housed by pairs in individual pens provided with self-feeders and automatic waterers. Necropsies were performed on equal numbers of pigs from each treatment group on days 14 and 15 post-treatment. Adult and larval worms were collected, identified and counted by standard parasitological techniques. All counts were transformed by Y=log10 (count+1) transformation prior to analysis. A two-way analysis of variance was conducted and treatment effect was tested for significance at the 5% level. Efficacies based on geometric means and optimal doses were as follows: Ascaris suum, 98.3% at 1.25; Metastrongylus spp., 100% at 0.75; Oesophagostomum quadrispinulatum, 100% at 1.50; and Trichuris suis, 93.5% at 0.75. Efficacy for O. dentatum was from 81.3% to 100%; however, the average number of O. dentatum (30) was too small for significance. Two species of lungworms were present, Metastrongylus apri and M. pudendotectus but they were not speciated at necropsy. As reported for several anthelmintics, the efficacy of moxidectin was variable for Trichuris. The highest efficacy was in the 0.75 dose group with six pigs harboring a few or no worms. The lowest efficacy was in the 1.25 group with only two pigs harboring a few or no worms. 相似文献
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Steenhard NR Jensen TK Baggesen DL Roepstorff A Møller K 《American journal of veterinary research》2002,63(1):130-136
OBJECTIVE: To determine interactions between Oesophagostomum spp and Salmonella ser. Typhimurium in pigs. ANIMALS: 30 healthy 5- to 6-week-old pigs. PROCEDURE: Pigs were allotted to 3 groups (n = 10 pigs/group) and treated as follows: group A was given Oesophagostomum dentatum and O quadrispinulatum; group B was given O dentatum, O quadrispinulatum, and S Typhimurium; and group C was given S Typhimurium only. Pigs in groups A and B were trickle infected with Oesophagostomum spp 3 times weekly throughout the study. After 19 days, groups B and C were inoculated once with S Typhimurium. One pig from each group was euthanatized on the day of Salmonella exposure and 2 and 4 days after Salmonella exposure. The remaining pigs were euthanatized on days 16 and 17 after Salmonella exposure. RESULTS: Pigs with dual infections of nematodes and bacteria (group B) excreted significantly higher amounts of S Typhimurium in feces, compared with nematode-free pigs (group C). In addition, group-B pigs excreted S Typhimurium on more days than pigs in group C. Salmonella Typhimurium was detected in the cecum and colon in the majority of pigs in group B, whereas S Typhimurium was only detected in the colon in pigs in group C. Immunohistochemical examination detected S Typhimurium in 7 of 9 pigs in group B but only 2 of 9 pigs in group C. CONCLUSIONS AND CLINICAL RELEVANCE: Interactions between intestinal nematodes and bacteria may play an important role in the dynamics of S Typhimurium infections. 相似文献
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根据OenBank上已发表的环孢子虫（Cyclospora）rDNA序列设计并合成1对引物，利用PCR技术时首次在牛体内发现的形态学特征与人环孢子虫（Cyclospora cayetanensis）极为相似的牛源环孢子虫的ITS-1＋序列进行了扩增。将PCR扩增出的片段纯化后，克隆至pGEM—TEasy载体后进行序列测定，并利用NCBI在线BLAST程序对测序结果进行了同源性比较和序列分析。分析结果显示，扩增的ITS-1＋大小为865bp的片段，包含18S部分序列（371bp）、ITS-1全序列（385bp）和5．8S部分序列（109bp）。序列同源性分析表明，该牛源环抱子虫为艾美尔科原虫，但不同于目前已知的各种艾美尔科原虫，可能是一种新发现的原虫。 相似文献
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In the present study, samples representing Bunostomum trigonocephalum and Bunostomum phlebotomum from sheep and cattle in Heilongjiang Province, China, were characterized and grouped genetically by the first (ITS-1) and second (ITS-2) internal transcribed spacers (ITS) of nuclear ribosomal DNA (rDNA). The rDNA region including the ITS-1, 5.8S, ITS-2, and flanking 18S and 28S rDNA sequences was amplified by polymerase chain reaction (PCR), then sequenced and compared with that of other members of the hookworms available in GenBank?, and phylogenetic relationships between them were reconstructed using the Maximum-Parsimony method. The ITS-1, 5.8S, and ITS-2 sequences of the sheep hookworm were 381, 153, and 231 bp in length, respectively, and the corresponding sequences of the cattle hookworm were 392, 153, and 240 bp in length. The identity of ITS sequences of B. trigonocephalum and B. phlebotomum from sheep and cattle was 87.4%. A PCR-linked restriction fragment length polymorphism (PCR-RFLP) assay using restriction endonuclease Nde I was established for the unequivocal differentiation of the two hookworm species. Phylogenetic analyses based on the ITS sequences revealed that B. trigonocephalum and B. phlebotomum were closely related, but they represent two different species. 相似文献