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1.
An epidemiological survey on a Theileria parasite infection of cattle in Northeast China was carried out using allele-specific PCR and DNA sequence analysis of the major piroplasm surface protein (MPSP) gene. The results showed that 14 of 104 blood samples were positive for Theileria by PCR. Among the positive cases, co-infection with various combinations of C- and I-type parasites was detected in 12 samples; no B- and Thai-type parasites were detected by allele-specific PCR. Phylogenetic analysis based on the MPSP gene sequences revealed that Theileria parasites with the MPSP types 1, 2, and 4 were distributed in Northeast China.  相似文献   

2.
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   

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.
Theileria orientalis is a benign protozoan species that is widely distributed in Japan, yet sometimes causes serious economic losses in the livestock industry. In this study, we conducted a molecular survey based on genes encoding the major piroplasm surface protein (MPSP) and p23 for T. orientalis detected in cattle grazing in southern areas of Japan, consisting of 2 farms in Kumamoto prefecture (Aso and Kuma districts) and 3 farms in Okinawa prefecture (Ishigaki, Iriomote, and Yonaguni Islands). High prevalence rates of T. orientalis infection were shown in all the cattle populations using the diagnostic MPSP- and p23-PCR assays. Phylogenetic analyses revealed 4 MPSP genotypes and 3 p23 genotypes. Furthermore, MPSP genotype-specific PCR methods were developed in this study and wide distributions of 5-district genotypes of T. orientalis were observed for the examined farms. Our results indicate that at least 5 types of T. orientalis exist in Kumamoto and Okinawa prefectures of Japan and that genotype-specific PCR assays are highly applicable for the quarantine of transported cattle and for epidemiological surveys of bovine theileriosis in Japan.  相似文献   

5.
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   

6.
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   

7.
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   

8.
Theileria buffeli, generally a benign parasite of cattle, has been reported in animals from Texas, Missouri and North Carolina. To date, there have been no reports of the parasite in cattle residing in northern portions of the US. An 8-year-old cow (Maine Anjou x Angus cross-bred) in Michigan presented with hemoglobinuria and a packed cell volume of 9. Blood films stained with Giemsa showed numerous intraerythrocytic parasites morphologically consistent with T. buffeli. The parasite was confirmed to be T. buffeli by SSU rRNA gene sequence analysis (SSU rRNA sequence, Type A). This represents the first report of this parasite in an animal in Michigan.  相似文献   

9.
In the present study, we have surveyed the presence of a bovine Theileria protozoan, Theileria orientalis, in Mongolian cattle and engorging tick populations from selected provinces and districts in Mongolia. The percentages of infection in the cattle and ticks ranged from 8.8 to 66.6 and from 3.7 to 73.3, respectively, on a per district basis. The genetic diversity of T. orientalis isolates was also studied, based on the protozoan gene encoding a major piroplasm surface protein (MPSP). At least five genotypes (types 1, 3, 5, 7, and N-3) of T. orientalis were found to be circulating among the Mongolian cattle and tick populations. In particular, types 3 and N-3 were common in most of the districts examined, while a strong geographical relationship among the genotypes was not detected in the present study. This is the first epidemiological report describing the presence of T. orientalis infection in Mongolian cattle.  相似文献   

10.
Theileria orientalis is a benign bovine protozoan parasite that occasionally causes serious economic loss in the livestock industry. We report the findings of a molecular epidemiological survey of T. orientalis in 94 Vietnamese yellow cattle, 43 water buffaloes, 21 sheep, 21 goats and 85 blood-sucking ticks of cattle in the Thua Thien Hue province of Vietnam. The major piroplasm surface protein (MPSP) gene of T. orientalis was detected using polymerase chain reaction from 13 cattle (13.8%), 11 water buffaloes (25.6%), 1 sheep (4.8%) and 9 ticks (10.6%). Phylogenetic analysis using MPSP gene sequences showed the presence of seven genotypes, four previously categorized genotypes (Types 1, 3, 5 and 7) and three new genotypes (Types N-1, N-2 and N-3).  相似文献   

11.
Theileria parva is the causative agent of Corridor disease in cattle in South Africa. The African buffalo (Syncerus caffer) is the reservoir host, and, as these animals are important for eco-tourism in South Africa, it is compulsory to test and certify them disease free prior to translocation. A T. parva-specific real-time polymerase chain reaction (PCR) test based on the small subunit ribosomal RNA (18S rRNA) gene is one of the tests used for the diagnosis of the parasite in buffalo and cattle in South Africa. However, because of the high similarity between the 18S rRNA gene sequences of T. parva and Theileria sp. (buffalo), the latter is also amplified by the real-time PCR primers, although it is not detected by the T. parva-specific hybridization probes. Preliminary sequencing studies have revealed a small number of sequence differences within the 18S rRNA gene in both species but the extent of this sequence variation is unknown. The aim of the current study was to sequence the 18S rRNA genes of T. parva and Theileria sp. (buffalo), and to determine whether all identified genotypes can be correctly detected by the real-time PCR assay. The reverse line blot (RLB) hybridization assay was used to identify T. parva and Theileria sp. (buffalo) positive samples from buffalo blood samples originating from the Kruger National Park, Hluhluwe-iMfolozi Park, the Greater Limpopo Transfrontier Park, and a private game ranch in the Hoedspruit area. T. parva and Theileria sp. (buffalo) were identified in 42% and 28%, respectively, of 252 samples, mainly as mixed infections. The full-length 18S rRNA gene of selected samples was amplified, cloned and sequenced. From a total of 20 sequences obtained, 10 grouped with previously published T. parva sequences from GenBank while 10 sequences grouped with a previously published Theileria sp. (buffalo) sequence. All these formed a monophyletic group with known pathogenic Theileria species. Our phylogenetic analyses confirm the distinction between Theileria sp. (buffalo) and T. parva and indicate the existence of a single group of T. parva and two Theileria sp. (buffalo) 18S rRNA gene variants in the African buffalo. Despite the observed variation in the full-length parasite 18S rRNA gene sequences, the area in the V4 hypervariable region where the RLB and real-time PCR hybridization probes were developed was relatively conserved. The T. parva specific real-time PCR assay was able to successfully detect all T. parva variants and, although amplicons were obtained from Theileria sp. (buffalo) DNA, none of the Theileria sp. (buffalo) 18S rRNA sequence variants were detected by the T. parva-specific hybridization probes.  相似文献   

12.
In the present study, we tried to detect DNA for ribosomal RNA genes of piroplasma parasites from the liver or blood of 43 Japanese serows (Capricornis crispus) in Iwate Prefecture of Japan by polymerase chain reaction. Approximately 500-bp amplicons were obtained in 35 (81.4%) of the 43 samples by amplification for V4 hyper-variable regions of the 18S rRNA gene, and the amplicons were considered to be DNA of Theileria species. The complete nucleotide sequences (1,700 or 1709 bp) of the 18S rRNA gene were determined in 20 samples and were divided into 5 genotypes that were phylogenetically separated into two different lineages showing a polyphyletic relation. The Theileria DNAs of the two different lineages were considered to be those of distinct species.  相似文献   

13.
The 18S rRNA gene and the piroplasm major immunodominant protein gene (p33/34) of Theileria from various subspecies of sika deer in 8 different locations of Japan were analyzed. The similarity between 633 bp partial sequences of the 18S rRNA gene among various subspecies of sika deer was found to be between 99.7% and 100%. While the percent identities of the 412 bp partial p33/34 gene sequence and deduced amino acid sequences between Theileria of sika deer from Yamaguchi Prefecture and those found in deer from other Prefectures, were comparatively low, 68.7% to 70.1% and 64.1% to 70.0% respectively. These findings suggest that there are at least two genetically distinct strains of Theileria of sika deer in Japan.  相似文献   

14.
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15.
We previously reported that small wild rodents in Japan harbor two types of novel Babesia microti-like parasites (designated as Hobetsu and Kobe types), but not the type commonly found in the northeastern United States (U.S. type) where human babesiosis is endemic. To determine whether these new types of parasites are distributed in places surrounding Japan, an epizootiologic survey was undertaken in three geographically distant areas in northeastern Eurasia; South Korea, Vladivostok in Russia, and Xinjiang in China. Blood samples were collected from a total of 387 animals comprising 24 species. DNAs extracted from the samples were tested by nested PCR targeting babesial nuclear small-subunit rRNA gene (rDNA), which revealed that small rodents harboring B. microti exist in all three survey areas. Sequence analysis showed that all PCR-positive samples had rDNA sequences virtually identical to that of U.S.-type B. microti. However, when beta-tubulin gene sequences were compared, evident geographic variations were seen. By use of primers specific for each of the beta-tubulin genes of Kobe-, Hobetsu-, and U.S.-type parasites, a type-specific PCR was developed. Parasite with Hobetsu- or Kobe-type sequence was not detected from any of the three survey areas. These findings suggest that U.S.-type B. microti is widely distributed among small wild mammals in temperate zones of not only North America, but also Eurasia, whereas that Hobetsu- and Kobe-type parasites may be uniquely distributed in Japan.  相似文献   

16.
Six Theileria spp. from cattle, buffalo and black goat were identified in the Hubei province of China. In order to study the taxonomic status of these parasites, phylogenetic analysis of 18S rRNA genes were carried out. The 18S rRNA genes from each isolate were amplified by the polymerase chain reaction and the approximate 1.75 kb products were cloned and sequenced. Phylogenetic analysis of these gene sequences revealed that the five parasites from buffalo and cattle belonged to the Theileria sergenti/buffeli/orientalis group. The parasite from the Chinese goat (Macheng-Hubei, DQ286802) was closely related to Theileria luwenshuni isolated from sheep in the north of China. This represent the first report on the use of molecular phylogeny to classify Theileria spp. obtained in the Hubei province, showing that Theileria spp. from ruminants found in Hubei province belongs to the benign group of Theileria spp.  相似文献   

17.
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   

18.
Theileria orientalis is usually a benign parasite but some genotypes cause infection and economic losses to the cattle industry. This study was carried out to determine T. orientalis genotypes in cattle. T. orientalis positive 63 sample were analyzed by amplifying the MPSP gene region by PCR. As a result of the SSCP analysis, samples with different band profiles were sent to the sequence analysis and genotypes were determined. T. orientalis genotype-specific PCR was performed to determine the mix genotypes. Type 1 (chitose), type 3 and type 1-type 3 mix were found positive 11.1%, 46%, and 17.5% respectively. In addition, phylogenetic analysis was performed to separate the chitose genotypes, and two samples were found in chitose A, one sample was found in chitose B. Although chitose A genotype is suggested to be more pathogenic than chitose B, but there is little evidence for this. As a result of this study, we showed the presence of pathogenic genotype T. orientalis in Turkey. Therefore, extensive epidemiological studies are required to understand the geographic distribution, different genotypes and clinical pathologies of T. orientalis.  相似文献   

19.
There are very few studies on the diversity and public health significance of Cryptosporidium species in zebu cattle and water buffaloes in developing countries. In this study, PCR-restriction fragment length polymorphism and DNA sequence analyses of the small-subunit (SSU) rRNA gene were used to genotype Cryptosporidium specimens from 12 zebu cattle calves, 16 water buffalo calves, and four swamp deer (Cervus duvaucelii) collected from the buffer zone of the Chitwan National Park, Nepal. All Cryptosporidium specimens from cattle and buffaloes belonged to Cryptosporidium ryanae, whereas those from deer belonged to Cryptosporidium ubiquitum. Comparison of the SSU rRNA gene sequences obtained with those from earlier studies has identified a nucleotide substitution unique to all C. ryanae isolates from Nepal, in addition to some sequence heterogeneity among different copies of the gene. The finding of the dominance of a unique C. ryanae variant in both zebu cattle and water buffaloes in Nepal indicates that there is unique cryptosporidiosis transmission in bovine animals in the study area, and cross-species transmission of some Cryptosporidium spp. can occur between related animal species sharing the same habitats.  相似文献   

20.
A molecular epidemiological survey of the protozoal parasites that cause equine piroplasmosis was conducted using samples collected from horses and zebra from different geographical locations in South Africa. A total of 488 samples were tested for the presence of Theileria equi and/or Babesia caballi using the reverse line blot hybridization assay. Ten percent of the samples hybridized to the Theileria/Babesia genus-specific probe and not to the B. caballi or T. equi species-specific probes, suggesting the presence of a novel species or genotype. The small subunit of rRNA gene (18S; ∼1600 bp) was amplified and sequenced from 33 of these 488 samples. Sequences were compared with published sequences from the public sequence databases. Twelve distinct T. equi and six B. caballi 18S rRNA sequences were identified. Alignments demonstrated extensive sequence variation in the V4 hypervariable region of the 18S rRNA gene within T. equi. Sequence variation was also found in B. caballi 18S rRNA genes, although there was less variation than observed for T. equi. Phylogenetic analysis based on 18S rRNA gene sequences revealed three T. equi clades and two B. caballi clades in South Africa. The extent of sequence heterogeneity detected within T. equi and B. caballi 18S rRNA genes was unexpected since concerted evolution is thought to maintain homogeneity within repeated gene families, including rRNA genes, in eukaryotes. The findings reported here show that careful examination of variants of the 18S rRNA gene of T. equi and B. caballi is required prior to the development of molecular diagnostic tests to detect these parasites in horses. Species-specific probes must be in designed in regions of the gene that are both conserved within and unique to each species.  相似文献   

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