首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 31 毫秒
1.
Benign Theileria parasites of cattle distributed in the Okinawa prefecture were characterized by allele-specific polymerase chain reaction (PCR) and DNA sequence analysis of the major piroplasm surface protein (MPSP) gene. Using universal or allele-specific primer sets, parasite DNA was amplified in 31 out of 48 blood samples obtained from beef cattle. Among the positive cases, mixed infections involving various combinations of I-, C-, and B-type parasites were detected in 24 (77.4%) samples. Phylogenetic analysis based on the MPSP gene sequences revealed that parasites with the MPSP types 1-5 and 7, exist within the Okinawa prefecture.  相似文献   

2.
During a year from 1999 to 2000, a total of 247 blood samples were collected from 214 cattle and 33 water buffaloes in 16 distinct geographical locations of Thailand and analyzed by allele-specific PCR amplification of major piroplasm surface protein (MPSP) genes of benign Theileria parasites. Four allelic MPSP gene types were determined namely C-type, I-type, B-type and Thai-type, which were originally designated from Japanese Theileria orientalis (Chitose, Ikeda), Australian T. buffeli (Warwick) and Thai T. sp. (Kamphaeng Saen), respectively. Only two allelic MPSP gene types were successively amplified from 204 (82.6%) blood samples. Among positive cases, 138 (67.6%) and 17 (8.3%) samples contained either Thai-type or C-type parasites, respectively, while 49 (24%) samples contained both types. However, nucleotide sequences of MPSP genes of Thai T. sp. amplified by C-type specific primers revealed higher (96.3%) similarity to Indonesian T. sp. rather than (87.8% similarity) to Japanese T. orientalis (Chitose) designated as C-type.  相似文献   

3.
Complete major piroplasm surface protein (MPSP) gene sequences of benign Theileria parasites were isolated from ticks of grazing cattle in Korea. A total of 556 tick samples were collected in five provinces: Chungbuk, Jeonbuk, Jeonnam, Gyeongbuk, and Jeju during 2010-2011. Fifteen samples from Chungbuk and Jeonnam were positive for the Theileria MPSP gene by PCR amplification using a specific primer set. A phylogenetic tree was constructed with the amplified gene sequences and 26 additional sequences published in GenBank. The benign Theileria parasites were classified into eight types, those isolated from Korean cattle ticks belonged to Types 1 (Ikeda), 2 (Chitose), 4, and 8. Types 2 and 4 were the most common types, with the rate of 40%, followed by Types 1 and 8 (with the rate of 13% and 7%, respectively). Nucleotide sequence identities of 23 theilerial MPSP sequences (15 MPSP gene sequences amplified and 8 sequences published) ranged from 67.3 to 99.8%. Multiple alignments of the deduced amino acid sequences also showed that each type was characterized by specific amino acids: 7 for Type 1, 9 for Type 2, 4 for Type 4, and 3 for Type 8.  相似文献   

4.
Twenty-eight field isolated Theileria parasite DNAs obtained from dairy and beef cattle in distinct geographical areas of Thailand were characterized by using polymerase chain reaction (PCR) amplification with six sets of oligonucleotide primers. Three sets of them were modified from two genes of immunodominant major piroplasm surface protein (MPSP) coding for 32 kDa (p32) of T. sergenti and 33/34 kDa (p33/34) of T. buffeli, and MPSP of Theileria spp.(Thai-isolate). The other three sets of primers were basically generated from three alleles of MPSP which were specific for Japanese T. sergenti-Ikeda stock (I-type), Japanese T. sergenti-Chitose stock (C-type) and Australian T. buffeli-Warwick stock (B1-type), respectively. The results indicated that 14 out of 28 isolates were amplified by the Thai-specific primer whereas 6 isolates were amplified by the p32 specific primer and the other 5 isolates were amplified by the p32 and Thai-specific primers. In addition, by using the allele-specific PCR, 14 out of 28 isolates contained C-type MPSP whereas 3 isolates contained B1 type parasites. Interestingly, 20 out of 28 isolates could be amplified by the Thai-specific primer. The majority of Theileria parasites distributed in Thailand contained Thai type parasites, whereas C-type parasites showed the mixed population with B1 and Thai type parasites. No I type parasite was detected.  相似文献   

5.
Bovine theileriosis was a kind of hemo-protozoan diseases that seriously hindered the sustainable development of cattle industry.In the present study, the infection of Theileria was detected using microscopic examination and species-specifc PCR of T.annulata, T.sergenti and T.sinensis from 18 blood samples collected from a breeding cattle farm in China.Then ITS and MPSP genes were amplified and cloned using universal primers of ITS and allele-specific primers of 4 major piroplasm surface protein (MPSP) from the positive samples.The sequences were used to make alignment, polymorphism and phylogeny analysis.The results showed that 3 samples were positive for Theileria and the 3 positive samples were all the T.sergenti infection.The amplification of allelic MPSP gene of T.sergenti from the 3 positive samples showed that two of them were single infection by Ikeda-type and another one was co-infection with both Chitose-type and Ikeda-type, while Buffeli-type and Thai-type were not detected.Moreover, on the basis of phylogenetic tree constructed with MPSP gene sequences, types 1 and 2 of MPSP were confirmed to be present in the cattle farm.The results revealed that there were T.sergenti infection in the breeding cattle farm, and these parasites at least with 2 allelic MPSP gene types were present, which indicated that the immune prevention and control of the disease became more complicated.Our research laid foundation of the further study on T.sergenti infection and disease prevention and control.  相似文献   

6.
牛泰勒虫病是严重危害养牛业可持续发展的血液原虫病,本试验采用血涂片镜检和特异性PCR检测技术,对中国某种牛场的18份血样进行了泰勒虫检测,然后分别用ITS基因通用引物和4种MPSP等位基因特异性引物自阳性样品中扩增出对应的基因,克隆测序后,进行序列比对和进化分析,确定泰勒虫基因型。结果显示,自18份牛血样中检出3份阳性样品,且全为瑟氏泰勒虫感染;3个阳性样品的瑟氏泰勒虫MPSP等位基因扩增结果显示,1个阳性样品为I (Ikeda) 和C (Chitose)型的混合感染,另2个样品为I型单一感染,而均无B (Buffeli)和Thai型;用扩增的MPSP基因测序,构建进化树,确认其感染的瑟氏泰勒虫存在MPSP 1型和2型。这些结果表明,该种牛场存在瑟氏泰勒虫感染,且同时存在2种MPSP等位基因型;MPSP等位基因的复杂性可能使该病的免疫防控更加困难。本试验结果为深入研究瑟氏泰勒虫感染情况及免疫防控提供了数据支持,并为养防一体做好监控。  相似文献   

7.
Benign Theileria species of cattle are found in most parts of the world. The major piroplasm surface protein (MPSP), a conserved protein in all Theileria species, has been used as a maker for epidemiological and phylogenetical studies of benign Theileria species. Parasites with Ikeda- or Chitose-type MPSP genes are dominant in Japan, but we report here mixed infection cases of Theileria parasites with an additional MPSP type parasite infecting cattle in Abashiri District, Hokkaido. The MPSP gene sequence found in the additional type was closely related to MPSP genes of Theileria parasites found in Southeast Asian countries, including Thailand (Narathiwat) and Indonesia (Java). Theileria parasites from the blood sample were also distinguishable from the Ikeda or Chitose type parasites by the small subunit (SSU) rRNA gene sequence analysis, and they are grouped into the SSU rRNA types C/D found in Korea, North America, and Spain. The present finding of mixed infections of cattle with three different types of Theileria makes epidemiological feature of bovine theileriosis in Japan more complex. We have designed a set of primers specific to this MPSP type in order to conduct further epidemiological study.  相似文献   

8.
The sensitivity of LAMP, PCR and microscopy to detect Theileria spp. and Trypanosoma congolense in field-derived bovine blood samples from Tanzania was evaluated and compared. No parasites were detected by microscopy. Furthermore, no bovine Theileria spp. were detected by LAMP and PCR from all the 24 samples collected from Arusha. Four and one out of 24 samples were positive for Theileria congolense infection by LAMP and PCR respectively while, 18 and nine out of 40 samples from Dar es Salaam were positive by LAMP and PCR for Theileria spp. Infection, respectively. Although all samples from Dar es Salaam were negative for Trypanosoma congolense infections by PCR, 12 out of 40 samples were LAMP positive. Whilst PCR is an established gene amplification method for the detection of Theileria and trypanosome parasites, this study introduces LAMP as an alternative molecular diagnostic tool that could be used in large-scale epidemiological surveys.  相似文献   

9.
为了解吉林省延边地区流行的羊泰勒虫种类,采用血涂片镜检和PCR方法对羊泰勒虫进行鉴定和遗传学分析。血涂片镜检观察发现,血涂片红细胞中存在圆形虫体。对羊泰勒虫MPSP基因生物信息学分析显示,MPSP编码的蛋白包含3个N-糖基化位点,14个潜在抗原表位,含有信号肽结构。建立系统进化树显示,分离到的3个虫株与Theileria luwenshunli(GQ281044)同源性为100%,亲缘关系较近,分离的羊泰勒虫为吕氏泰勒虫。由该试验结果可以得出,吉林省延边地区流行的羊泰勒虫为吕氏泰勒虫。  相似文献   

10.
A survey of Theileria parasites in cattle in eastern Turkey was carried out using specific polymerase chain reaction. A total of 252 blood samples were collected from clinically healthy cattle between June and July 2004. Of 252 blood samples examined, 41 (16%) were positive for piroplasms by microscopy, whereas 114 (45%) were positive for the presence of at least one species of Theileria by PCR. The percentages of positive animals for Theileria annulata and benign Theileria species (Theileria sergenti/buffeli/orientalis) were 39% (99/252) and 7% (18/252), respectively. By allele-specific PCR examination of 18 field isolates which were positive for benign Theileria parasites, 8 samples were only amplified by B-type specific primers and 10 samples were amplified by both of the B and C-type specific primers, indicating a mixed infection with B and C-type of the parasite. None of the field isolates was amplified by I-type specific primers. Three samples were co-infected with T. annulata and benign Theileria parasites. Two of them which were infected with B-type parasite were also infected with T. annulata, the other sample which was infected both of B and C-type parasites was also infected with T. annulata. A total of 724 ixodid ticks were collected from the cattle. Hyalomma anatolicum anatolicum was the dominant species with 32% (230/724) in the region. H. a. excavatum, Boophylus annulatus and Rhipicephalus bursa represented 25% (183/724), 19% (140/724) and 15% (112/724) of the total number of ticks, respectively. R. sanguineus was the minor species and represented 8% (59/724) of the tick population.  相似文献   

11.
A Theileria species was detected by PCR in blood samples collected from dogs in the Pietermaritzburg area and was also found in dogs presented at the Outpatients Clinic of the Onderstepoort Veterinary Academic Hospital (OVAH), in the Pretoria area, South Africa. In the Pietermaritzburg area, 79 of the 192 samples were positive, while 3 out of 1137 of the Onderstepoort samples were positive. Three positive samples from Pietermaritzburg were co-infected with Ehrlichia canis. PCR positive samples were further analysed by the Reverse Line Blot (RLB) and sequence analysis. Phylogenetic analysis of the 18S rRNA full-length gene sequences of one sample (VT12) from Pietermaritzburg and two samples from OVAH (BC281 and BC295) revealed a close relationship with sequences of Theileria species (sable). Clinical signs of the dogs that were examined at Pietermaritzburg and OVAH included an immune-mediated condition with severe thrombocytopenia. These findings identify a Theileria sp. in dogs for the first time in South Africa and add yet another microorganism to the growing list of haemoprotozoan parasites infecting dogs worldwide. The clinical significance of this infection in dogs is poorly resolved.  相似文献   

12.
套式PCR扩增山羊吕氏泰勒虫18S rRNA基因   总被引：1，自引：1，他引：0  
泰勒虫是一种危害动物的重要血液寄生性原虫,常寄生于牛、羊、骆驼和其他野生动物,在中国的东北、西北等地较为流行。采集安徽定远县某山羊场疑似焦虫病的山羊血样,首先采用血涂片法检查,再用Blood DNA&Tissue kit提取血液基因组,参照Kim和Wei的方法设计2对引物用于泰勒虫18S rRNA基因的扩增,并对该方法进行敏感性和特异性分析。结果显示:血涂片检查明显可见红细胞内有典型的虫体,大小为0.6~2μm,初步怀疑为泰勒虫(Theileria);PCR扩增可扩增出359 bp大小目的片段,与预期结果相一致;基因序列同源性表明,该泰勒虫分离株基因与已报道泰勒虫毒株(JQ926740.1)核苷酸同源性最高,可达99.72%;在遗传进化方面,所分离的泰勒虫和吕氏泰勒虫(Theileria luwenshuni)Nanjingdong(JQ926740.1)最接近,而且在一个分支上。本试验所建立的套式PCR具有良好的特异性,且敏感性较高,最低测出量是3.8 fg/μL。本次分离的羊血液原虫为吕氏泰勒虫。  相似文献   

13.
  相似文献   

14.
羊泰勒虫PCR检测方法的建立和初步应用   总被引：1，自引：0，他引：1  
利用羊泰勒虫18SrRNA基因的序列特点,设计合成种特异性引物,建立羊泰勒虫PCR检测方法,该方法能特异性扩增398bp的羊泰勒虫18SrRNA基因片段,而对羊巴贝斯虫、羊无浆体、牛环形泰勒虫和牛伊氏锥虫的基因组DNA没有扩增带出现。对羊泰勒虫基因组DNA的最小检测量为0.12fgDNA。通过检测124份临床样品,24份为羊泰勒虫感染阳性,其余为阴性。结果表明,建立的PCR检测方法具有极高的敏感性和特异性,可用于羊泰勒虫病和临床健康带虫羊的诊断。  相似文献   

15.
为建立特异、敏感、快速的二温式PCR诊断方法,根据牛环形泰勒虫裂殖子表面抗原(tams1)基因,设计了一对特异性引物,扩增出大小为154bp基因片段,经克隆、测序分析,与已知基因序列的相似性为96%。用建立的牛环形泰勒虫病二温式PCR诊断方法,对从新疆牛环形泰勒虫病流行地区采集的50份全血样品进行诊断,阳性率为88%,而血涂片检出的阳性率只有58%。经试验验证,该方法具有特异性高、敏感性强、重复性和稳定性好等优点。表明本试验所建立的二温式PCR诊断方法可用于牛环形泰勒虫病的临床诊断、隐性感染检测和流行病学调查。  相似文献   

16.
Ge Y  Pan W  Yin H 《Veterinary parasitology》2012,186(3-4):466-469
Theileriosis is an important tick-borne hemoprotozoan disease, which can cause severe economic loss in animal husbandry. In this paper, one hundred peripheral blood samples of goats and sheep from southeastern China were examined for the Theileria infection. A region of Theileria 18S rRNA gene was amplified by nested PCR in 26 samples. All the nested PCR amplicons were cloned and sequenced. Alignment analysis has shown that these sequences are highly homologus to each other with identities from 99.2% to 100%. Blast the sequences against NCBI database indicated 99% homology with Theileria sp. China 1 (Theileria luwenshuni). Phylogenetic tree has also shown that the newly identified Theileria are in the same clade with T. luwenshuni. The results have revealed a relatively high prevalence of Theileria in some areas of southeastern China and little genetic diversity in these infections.  相似文献   

17.
Piroplasms are tick-transmitted, intracellular, hemoprotozoan parasites that cause anorexia, fever, anemia, and icterus. Theileriosis is caused by Theileria sergenti and causes major economic losses in grazing cattle in Japan and Korea. In May 2003, we examined the antigenic diversity of the major piroplasm surface protein (MPSP) gene in 35 healthy Jeju black cattle that were born and raised at the National Institute of Subtropical Agriculture. On microscopic examination of Giemsa-stained blood smears, 9 of 35 cattle had intra-erythrocytic piroplasms. Hematological data were within normal range for all 35 cattle. Amplification of DNA from all blood samples using universal MPSP gene primers showed mixed infections with C, I, and B type Theileria spp. Type C was identified in 20 of 35 blood samples, and type B was identified in 17 samples. Allelic variation was seen in type B.  相似文献   

18.
A survey of Theileria parasite infection in cattle in Cambodia and Vietnam was carried out by using allele-specific polymerase chain reaction. A total of 137 blood samples from draught animals in Cambodia and 40 blood samples from dairy cattle in Vietnam were analyzed. In Cambodia, 69 out of 137(50.4%) samples were PCR-positive containing mainly the Thai and the C type parasites. In Vietnam, 11 (27.5%) samples were positive and all were of the Thai type parasite.  相似文献   

19.
为寻求快速、有效检测羊泰勒虫的PCR方法,本试验建立了检测羊泰勒虫18SrRNA基因和表面蛋白基因的两种常规PCR方法和一种检测18SrRNA基因的半套式PCR方法,并从其敏感性和临床样本检出率等方面进行了比较。结果显示:上述方法检测羊泰勒虫基因组DNA的最小检测量分别为1.6fg/μL、16fg/μL和0.016fg/μL;检测临床样本阳性检出率分别为31.37%(16/51)、17.64%(9/51)和45.10%(23/51)。3种方法中,检测18SrRNA基因的半套式PCR方法敏感性和临床样本检出率最高,其次为检测18SrRNA基因的常规PCR方法,最后为检测表面蛋白基因的常规PCR方法。结果说明,所建立的半套式PCR方法是一种较好的羊泰勒虫检测方法。  相似文献   

20.
Between September 2010 and November 2011, 350 EDTA blood samples were received from 73 Australian cattle herds, as cases suspected to be infected with Theileria orientalis. Beef cattle were predominantly affected, with Angus and Angus-crossbred cattle representing 48% of smear positive samples examined. DNA extracts were tested in conventional polymerase chain reaction (PCR) assays for genes encoding the p32, Ikeda, Chitose and Buffeli major piroplasm surface proteins (MPSP). PCR findings were compared with results of clinical pathology examinations of stained blood smears for parasitaemia and packed cell volume (PCV). PCR testing was much more sensitive than clinical pathology examinations in detecting T. orientalis infections, and concurrent testing of neat and diluted extracts gave significantly more PCR positive results than testing of neat extract alone. Significant associations and correlations were shown between PCR results of p32 and Ikeda assays with PCV levels indicative of anaemia, and with the level of parasitaemia estimated by smears. A high proportion of samples had concurrent Ikeda and Chitose infection, and significantly more clinical cases of theileriosis were associated with the Ikeda MPSP type as the sole infection, compared with sole infection with types Chitose or Buffeli. The findings indicate Ikeda type organisms were significantly associated with clinical parameters of theileriosis in cattle herds in eastern Australia, and that this type is most likely to be responsible for outbreaks of theileriosis experienced in affected Australian herds. In New South Wales, 11 of 14 regulatory districts yielded Ikeda positive samples, with five (Mid-Coast, Cumberland, Central North, Hume and Lachlan) containing 234/307 (76%) of the Ikeda positive samples.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号