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1.
The present study examined the relationship among individual Sarcoptes scabiei mites from 13 wild mammalian populations belonging to nine species in four European countries using the second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA) as genetic marker. The ITS-2 plus primer flanking 5.8S and 28S rDNA (ITS-2+) was amplified from individual mites by polymerase chain reaction (PCR) and the amplicons were sequenced directly. A total of 148 ITS-2+ sequences of 404 bp in length were obtained and 67 variable sites were identified (16.59%). UPGMA analyses did not show any geographical or host-specific clustering, and a similar outcome was obtained using population pairwise Fst statistics. These results demonstrated that ITS-2 rDNA does not appear to be suitable for examining genetic diversity among mite populations.  相似文献   

2.
郝桂英  何学谦 《中国畜牧兽医》2015,42(12):3167-3172
应用保守引物BD1和BD2对7个鸡蛔虫凉山州分离株的核糖体DNA内转录间隔区(ITS)及5.8S rDNA序列进行PCR扩增和序列测定,并用ITS-1、ITS-2序列重构鸡蛔虫与其他蛔虫的系统发育关系。测序结果显示所获得的鸡蛔虫ITS及5.8S rDNA序列大小为974~989 bp,同源性为98.9%~100.0%。其中ITS-1、5.8S rDNA和ITS-2片段大小分别为473~481、157和337~359 bp,同源性分别为98.5%~100.0%、100.0% 和98.5%~100.0%。系统发育树显示所有鸡蛔虫分离株聚在同一分支,能与其他蛔虫相区别。研究结果表明,鸡蛔虫的ITS-1、ITS-2序列种内变异小,但种间差异大,故可作为分子标记用于鸡蛔虫的虫种鉴定,为鸡蛔虫的分子分类、分子流行病学调查和种群遗传的进一步研究奠定基础。  相似文献   

3.
本研究旨在阐明黄鳝胃瘤线虫湖南分离株的核糖体DNA(rDNA)内转录间隔区(ITS)及5.8 S rDNA序列的遗传变异情况,并用ITS序列重构胃瘤线虫与其它线虫的种群遗传关系.利用聚合酶链反应(PCR)扩增胃瘤线虫rDNA的ITS-1、5.8S及ITS-2片段,将PCR扩增出的片段纯化后克隆至pGEM-T Easy载体,重组质粒通过菌落PCR鉴定后,对阳性菌落进行序列测定并进行序列分析.结果显示所获得的胃瘤线虫ITS及5.8 S rDNA序列总长存在一定差异(922~927 bp),其中包含部分的18S、28 S及全部的ITS-1 (350~351 bp)、5.8S(102 bp)及ITS-2 (340~344 bp)序列.本研究系国内首次报道胃瘤线虫的ITS序列,其结果为黄鳝胃瘤线虫的分类鉴定以及进一步的分子流行病学调查和群体遗传研究奠定了基础.  相似文献   

4.
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   

5.
Isolates of the rumen fluke Calicophoron daubneyi (Digenea: Paramphistomidae) from various hosts and three locations in southern Italy were characterized genetically. The second internal transcribed spacer (ITS-2) of ribosomal DNA (rDNA) plus flanking 5.8S and 28S sequence (ITS-2+) was amplified from individual rumen flukes by PCR. PCR-linked restriction fragment length polymorphism (PCR-RFLP) analysis was performed using four different restriction endonucleases, and PCR products were sequenced. The PCR analyses from all the C. daubneyi specimens produced identical fragments, and the PCR-RFLP analyses did not show, with respect to any of the four restriction endonucleases, any differences between the C. daubneyi specimens. The sequence analyses of the ITS-2+ from each of the C. daubneyi specimens showed them all to be 428 bp, and composed of the entire ITS-2 sequence (282 bp) plus the two partial flanking conserved sequences, 5.8S (99 bp) and 28S (47 bp). No intra-specific variation was observed in the nucleotide composition of the ITS-2+ (homology=100%). There was, however, an observable inter-specific variation between the ITS-2+ of C. daubneyi and the ITS-2+ of both Calicophoron calicophorum (homology=97.2 %) and Calicophoronmicrobothrioides (homology=97.4 %), both previously deposited in the GenBank. The finding of the present study shows that, as has already demonstrated for other parasitic helminths, ITS-2 can serve as an effective genetic marker for the molecular identification of paramphistomes, and as a useful tool for developing molecular epidemiological techniques for the study of C. daubneyi transmission patterns and prevalence in definitive and intermediate hosts.  相似文献   

6.
Coccidiosis of chickens caused by protozoan parasites of the genus Eimeria (Coccidia: Eimeriidae) is an enteric disease that results in great economic losses throughout the world, including Taiwan. Using polymerase chain reaction (PCR) with primers specific for the second internal transcribed spacer (ITS-2) of ribosomal DNA (rDNA), three species of Eimeria, E. tenella, E. maxima, and E. acervulina have been successfully characterised from chickens in Taiwan. The sizes of PCR products from various isolates representing these three species were between 370 and 580 base pairs (bp). After cloning and sequencing of the PCR products, high nucleotide sequence identity (96.8-100%) was observed within a species. In addition, ITS-2 nucleotide sequences for E. tenella had higher homology (98.5-99.3%) than E. maxima (81.6-96.5%) when compared with appropriate sequences deposited in GenBank. To our knowledge, this is the first report of a 412-bp ITS-2 sequence for E. acervulina from chickens.  相似文献   

7.
To differentiate the morphologically similar pinworms of the common laboratory rodents, such as Syphacia obvelata and Syphacia muris, we amplified and sequenced the region spanning the internal transcribed spacer 1 (ITS-1), 5.8S gene, and ITS-2 of the ribosomal DNA followed by designing of species-specific primers for future use in the identification of the worms. It was observed that S. obvelata, S. muris and Aspiculuris tetraptera can be differentiated from each other based on their rDNA sequences. This is the first report of the ITS-1, 5.8S, and ITS-2 of the rDNA of the three aforementioned rodent pinworm species. The use of restriction endonucleases, AluI or RsaI, further allowed the delineation of the three species. Moreover, we also constructed species-specific primers that were designed for unique regions of the ITS-2 of the three species. This approach allowed their specific identification with no amplicons being amplified from heterogenous DNA samples, and sequencing confirmed the identity of the sequences amplified. Thus, the use of these specific primers along with PCR-RFLP can serve as useful tools for the identification of pinworms in rats, mice, and wild rodents.  相似文献   

8.
Isolates of Fasciola (Platyhelminthes: Trematoda: Digenea) from different host species and geographical locations in Mainland China were characterised genetically. The second internal transcribed spacer (ITS-2) of nuclear ribosomal DNA (rDNA) was amplified from individual trematodes by polymerase chain reaction (PCR), and the representative amplicons were cloned and sequenced. The length of the ITS-2 sequences was 361-362bp for all Chinese Fasciola specimens sequenced. While there was no variation in length or composition of the ITS-2 sequences among multiple specimens from France, Sichuan and Guangxi, sequence difference of 1.7% (6/362) was detected between specimens from France and Sichuan, and those from Guangxi. Based on ITS-2 sequence data, it was concluded that the Fasciola from Sichuan represented Fasciola hepatica, the one from Guangxi represented Fasciola gigantica and the one from sheep from Heilongjiang may represent an "intermediate genotype", as its ITS-2 sequences were unique in that two different ITS-2 sequences exist in the rDNA array within a single Fasciola worm. One of the sequences is identical to that of F. hepatica, and the other is almost identical to that of F. gigantica in that nucleotides at five of the six polymorphic positions represent F. gigantica. This microheterogeneity is possibly due to sequence polymorphism among copies of the ITS-2 array within the same worm. Based on the sequence differences, a PCR-linked restriction fragment length polymorphism (PCR-RFLP) assay was established for the unequivocal delineation of the Fasciola spp. from Mainland China using restriction endonuclease Hsp92II or RcaI. This assay should provide a valuable tool for the molecular identification and for studying the ecology and population genetic structures of Fasciola spp. from Mainland China and elsewhere.  相似文献   

9.
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   

10.
3种冠环线虫rDNA-ITS的PCR扩增及序列分析   总被引:1,自引:1,他引:0  
本试验利用PCR扩增3种冠环线虫5个样品的核糖体DNA内转录间隔区(ITS)及5.8S片段,将PCR扩增产物纯化后直接进行序列测定和分析。序列比对和分析结果显示,所测样品ITS1-5.8S-ITS2的长度范围为748~843 bp,总变异位点(包括gaps)119个,简约信息位点18个;其中ITS1和ITS2的长度范围分别为367~370 bp和228~320 bp,变异位点分别为14个和105个,简约信息位点均为9个。所有测试样品的5.8S片段完全相同,长度为153 bp。5条序列ITS1区的G+C含量(48.0%~48.5%)明显高于ITS2区(37.7%~40.3%)。通过序列两两比对,3种冠环线虫ITS1和ITS2的种间差异性分别为1.9%~3.5%和5.6%~31.8%;而种内差异性分别为0~0.5%和0~0.9%。并且所测序列与GenBank中已知序列的同源性为99.07%~99.41%。本研究认为,ITS序列可以作为冠环线虫种类鉴定的分子标记。  相似文献   

11.
斑马蛔虫ITS及5.8SrDNA的克隆及进化分析   总被引:1,自引:0,他引:1  
胡鹏辉 《动物检疫》2013,(12):62-65
研究从斑马体内分离的蛔虫的核糖体DNA内转录间隔区(ITS)及5.8SrDNA序列的遗传变异情况,并用ITS序列重构斑马蛔虫与其它蛔虫的种群遗传关系。利用聚合酶链反应(PCR)扩增斑马蛔虫rDNA的ITS-1、5.8S及ITS-2片段,将PCR扩增出的片段纯化后克隆至pGEM.TEasy载体,重组质粒通过菌落PCR鉴定后,对阳性菌落进行序列测定并进行序列分析。结果显示所获得的斑马蛔虫ITS及5.8SrDNA序列总长为892bp,包含部分的18S、28S及全部的ITS,1、5.8S及ITS.2序列。证实从斑马体内分离的蛔虫为马副蛔虫,从而为斑马蛔虫的分类鉴定以及进一步的分子流行病学调查奠定了基础。  相似文献   

12.
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   

13.
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   

14.
美洲狮和亚洲黑熊蛔虫ITS序列扩增及序列分析   总被引:1,自引:1,他引:0  
以采自广州动物园美洲狮和亚洲黑熊体内的蛔虫样品为研究对象,提取样品的总DNA,以保守引物对核糖体DNA内转录间隔区(ITS)序列进行PCR扩增、测序及网上比对。结果表明,美洲狮体内样品获得与GenBankTM公布的狮弓首蛔虫相似性很高的ITS-1、ITS-2和5.8S序列,亚洲黑熊体内样品获得与GenBankTM公布的转移拜林蛔虫相似性很高的ITS-2序列,并首次获得样品的ITS-1与5.8S序列。序列分析结果表明,美洲狮体内蛔虫样品为狮弓首蛔虫,亚洲黑熊体内蛔虫样品为转移拜林蛔虫。  相似文献   

15.
Single-strand conformation polymorphism (SSCP) was used to genetically differentiate morphologically indistinguishable first-stage larvae (L(1)) of the six species of elaphostrongyline nematodes. A partial fragment (317-336bp) of the first internal transcribed spacer (pITS-1) plus 5' flanking region (76bp of the 18S gene) of the nuclear ribosomal DNA (rDNA) was amplified from individual L(1) of known identity and subjected to SSCP. The results showed that the four species of elaphostrongylines found in North American cervids, Parelaphostrongylus tenuis, P. andersoni, P. odocoilei and Elaphostrongylus rangiferi, could be distinguished from one another based on their distinct (i.e. species-specific) SSCP profiles. In addition, E. alces, a species that occurs in moose in Fennoscandinavia, also had a distinct SSCP profile with respect to the other species of elaphostrongylines. However, the SSCP profiles of E. cervi could not be distinguished from those of E. rangiferi because of a lack of interspecific sequence differences in this region of the ITS-1. The distinct SSCP profiles for the other species were consistent with the interspecific differences in ITS-1 sequences, which ranged from 2 (between P. tenuis and P. andersoni) to 59bp (between genera). The pITS-1 SSCP approach was also used to identify unknown elaphostrongyline L(1) from different hosts and localities in North America. The ability to distinguish between L(1) of the four elaphostrongyline species that occur in North American cervids has important diagnostic and epidemiological implications.  相似文献   

16.
Nematodes of the family Heligmonellidae (Heligmosomoidea; Trichostrongylina) reside in the digestive tracts of rodents and lagomorphs. Although this family contains large numbers of genera and species, genetic information on the Heligmonellidae is very limited. We collected and isolated adult worms of three species in Japan that belong to the family Heligmonellidae, namely Heligmonoides speciosus (Konno, 1963) Durette-Desset, 1970 (Hs) from Apodemus argenteus, Orientostrongylus ezoensis Tada, 1975 (Oe) from Rattus norvegicus and Lagostrongylus leporis (Schulz, 1931) (Ll) from Pentalagus furnessi, and sequenced the entire internal transcribed spacer regions, ITS-1 and ITS-2 of ribosomal DNA. ITS-1 of Hs, Oe and Ll was 426, 468 and 449 bp in length, and had a G+C content of about 41, 41 and 37 %, respectively. ITS-2 of Hs, Oe and Ll was 297, 319 and 276 bp in length and had a G+C content of about 38, 40 and 28%, respectively. The data of Hs, Oe and Ll were compared with those of two other known species within the family Heligmonellidae, Calorinensis minutus (Dujardin, 1845) (Cm) and Nippostrogylus brasiliensis (Travassos, 1914) (Nb), and with those of two species of Heligmosomidae (Heligmosomoidea), Heligmosomoides polygyrus bakeri and Ohbayashinema erbaevae. Phylogenetic analysis placed Hs, Oe and Ll in the same clade with Cm and Nb, forming a Heligmonellidae branch in both ITS-1 and ITS-2, separate from the Heligmosomoidea branch. These results demonstrated that the ITS-1 and ITS-2 sequences are useful for differentiating the Heligmonellidae nematode species. This study is the first to describe the ITS-1 and ITS-2 sequences of Hs, Oe and Ll.  相似文献   

17.
湖南省猬迭宫绦虫ITS及5.8S rDNA的克隆及序列分析   总被引:1,自引:1,他引:0  
利用聚合酶链反应(PCR)扩增猬迭宫绦虫rDNA的ITS-1、5.8S及ITS-2片段,将PCR扩增出的片段纯化后克隆至pGEM-T Easy载体,重组质粒通过菌落PCR鉴定后,对阳性菌落进行序列测定并进行序列分析。结果显示,所获得的ITS及5.8S rDNA序列总长存在一定差异,为1 369~1 393 bp,包含部分的18、28S及全部的ITS-1(662~687 bp)5、.8S(138 bp)及ITS-2(457~475 bp)序列。由于猬迭宫绦虫ITS序列种内相对保守,种间差异较大,故可作为种间遗传变异研究的标记。  相似文献   

18.
根据Genebank网站公布的蜜蜂球囊菌ITSl.5.8s,ITS2 rDNA保守序列(U68313)设计出一对特异性引物ASCU和ASCD,可特异性的扩增蜜蜂球囊菌ITSI,5.8srRNA,ITS2序列上大小为471 bp的片段.优化了PCR最佳反应条件和体系;特异性试验结果表明与蜜蜂幼虫芽孢杆菌、蜂房蜜蜂球菌、蜜蜂败血杆菌无交叉反应,具有良好的特异性.敏感性试验结果表明敏感性可达7CFU/mL的蜜蜂球囊菌.通过将定量的蜜蜂球囊菌添加到蜂蜜、花粉、蜂胶和蜂王浆等蜂产品中进行模拟检疫,结果显示所建立的PCR检测方法适用于上述蜂产品中蜜蜂球囊菌的检疫.该方法与病原菌分离培养等传统检疫方法相比较,具有快速、灵敏、特异等优点,可用于蜜蜂及蜂产品中白垩病的进出口检疫及快速诊断.  相似文献   

19.
The aim of this study with horses and a few ponies naturally infected with tapeworms was to confirm in clinical trials the efficacy and safety of a praziquantel horse paste 9%. The field trials were conducted in 1997 and 1998 in Canada, France, Germany and New Zealand. A secondary aim of the study in Canada was to determine if a 24h post-treatment fecal sample provides the best estimate of the prevalence of tapeworms in horses when using a fecal examination technique. Fecal samples were taken from each of 1062 animals at least three times pre-treatment (PRT). In Canada, fecal samples were examined using the Cornell-Wisconsin centrifugal flotation technique, and in France, Germany and New Zealand using a centrifugation/flotation technique. In each trial, the animals were randomized into two treatment groups: praziquantel horse paste 9% at 1mg/kg body weight (BW) and untreated. Fecal samples were taken from each animal nine times post-treatment and over a period of 5 weeks. In Canada, a fecal sample was taken also at 24h after treatment. Personnel examining the samples were "blinded" to treatment groups. On the day of treatment, each treated animal was examined for adverse reactions to the paste 10min after treatment and then hourly for 4h. Thereafter, each animal was examined once daily for 5 weeks. In Canada, Germany and New Zealand, the only tapeworm egg found was Anoplocephala perfoliata. In France, A. perfoliata was the most common species and a few animals had A. magna and Paranoplocephala mamillana. The prevalence of A. perfoliata among animals sampled in Canada, France, Germany and New Zealand was 51.8, 34.4, 13.1 and 26.2%, respectively. A total of 248 animals were treated with the praziquantel paste and all except one accepted it readily. There were 292 animals completing the study, 219 treated and 73 untreated. In Canada, Germany and New Zealand, the efficacy of the praziquantel horse paste 9% against A. perfoliata was 100%. In France, the efficacy against A. perfoliata, A. magna and P. mamillana was 90.9, 100 and 100%, respectively. The best estimate of prevalence for A. perfoliata in a herd was derived from fecal samples taken 24h after treatment. At 24h, 22 of 23 treated horses were positive, whereas on any day pre-treatment fewer horses were positive. Adverse reactions observed were mild to moderate colic and in only two treated horses.  相似文献   

20.
The objective of this study was to confirm the presence of seven species of Eimeria involved in chicken coccidiosis in Australia by comparing internal transcribed spacer 1 (ITS-1) sequences, ITS-1 polymerase chain reaction (PCR) methods and to apply phylogenetic analysis to assess evolutionary relationships of Australian isolates. Twenty-two distinct ITS-1 regions of 15 Australian Eimeria isolates were sequenced, and analysed using maximum parsimony, distance and maximum likelihood methods. Poor bootstrap support, resulting from high ITS-1 sequence heterogeneity between all species groups, resulted in polychotomy of the Eimeria species in all three trees generated by these analyses. Percentage identity analyses revealed two distant ITS-1 lineages in both E. mitis and E. maxima at the same levels that separate the two species E. tenella and E. necatrix. One E. maxima lineage consisted of Australian isolates, the other American isolates, with one European sequence (originating from the same isolate) in each lineage. One Australian E. praecox sequence was only distantly related (33% variation) to three E. praecox sequences from Australian and European isolates. Short and long ITS-1 variants were isolated from both E. tenella (cloned line) and E. necatrix isolates with deletions (106 and 73 bp, respectively) in the short variants within the 3' region of the ITS-1 sequence. ITS-1 sequences of strains of both E. brunetti and E. acervulina species varied the least. Apart from E. maxima, all of the ITS-1 sequences of the six remaining individual species clustered to the exclusion of other species in all phylogenetic trees. Published ITS-1 tests for E. necatrix, E. acervulina, E. brunetti and E. tenella, combined with three new tests for E. mitis, E. praecox and Australian E. maxima amplified all respective Australian isolates specifically in a nested format using conserved ITS-1 PCR products as template to improve the sensitivity. All PCR tests were confirmed against a collection of 24 Australian chicken Eimeria isolates and contaminating species were detected in some instances. In conclusion, once the genetic variation between species and strains is determined, the ITS-1 is a good target for the development of species-specific assays, but the ITS-1 sequences alone do not seem suitable for the confirmation of phylogenetic inferences for these species. This study reports the first attempt at the analysis of the phylogeny and sequence comparison of the Eimeria species involved in chicken coccidiosis in Australia.  相似文献   

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