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1.
Accurate identification of the bovine pathogen Tritrichomonas foetus is sometimes complicated by the presence of other trichomonadid protozoa in clinical samples. A highly specific and reproducible approach for differentiating 3 common types of bovine trichomonadid protozoa found in the bovine preputial cavity, T. foetus, Pentatrichomonas hominis, and a Tetratrichomonas species, was developed using polymerase chain reaction (PCR) and restriction fragment length polymorphism (RFLP) analysis. Universal trichomonadid protozoa primers, TFR1 and TFR2, were used to amplify the 5.85 rRNA gene and internal transcribed spacer regions (ITSRs), and the products were digested with the restriction enzyme HpyCH4IV. Restriction fragment length polymorphism analysis was performed on 55 trichomonad isolates from bovine preputial washing and scraping samples. The RFLP results correlated 100% with 5.85 rRNA gene and ITSR sequence resultsand PCR results with primers specific for T. foetus. The results of this study demonstrate that PCR and RFLP analysis can be used in lieu of DNA sequencing to identify the specific trichomonadid protozoa isolated from the bovine preputial cavity.  相似文献   

2.
Preputial fluids from 567 virgin Angus and Hereford bulls, 1-2 years old, were inoculated into Sutherland medium, and approximately 8.4% produced cultures with a protozoan suggestive of Tritrichomonas foetus. Under brightfield microscopy, large numbers of single-celled motile organisms with multiple anterior flagellae, a posterior flagellum, axostyle, and a visible undulating membrane were detectable. Motility was jerky and rolling, as described for T. foetus. Air-dried smears of cultures stained with Giemsa or Diff-Quick + iodine revealed an organism similar to T. foetus, although somewhat more rounded. Several organisms appeared to have four anterior flagellae. Scanning electron microscopy (5000x) of representative samples revealed four anterior flagellae on most organisms, and an axostyle that was consistently longer than that seen in T. foetus. Using pan-trichomonal primers and T. foetus-specific primers in a polymerase chain reaction (PCR) assay, amplification products of 372bp were detected in all virgin bull isolates, but only with the pan-trichomonal primers. Positive control isolates of T. foetus yielded amplification products of the expected size (372 and 347bp) with the two sets of primers, respectively. We conclude that these protozoa are not T. foetus, and note the similarity of these findings with those reported earlier in North American beef cattle. Because in several countries there is no legal treatment for bovine trichomonosis, veterinarians recommend slaughter of bulls with positive preputial cultures. The existence of easily mis-identified non-T. foetus trichomonads in the bovine prepuce suggests that the current "gold standard" diagnostic test (culture of preputial scrapings or washings) should be augmented with a more specific confirming test, such as the PCR employed in this study.  相似文献   

3.
A 12-day-old nestling Gouldian finch ( Erythrura [Chloebia] gouldiae ) was presented for investigation of a mortality problem in nestling finches raised by Bengalese finch foster parents. On histological examination, large numbers of spores consistent with a microsporidian organism were present within the small intestinal mucosa. Electron microscopy and molecular studies (sequencing the 5' end of the ssu rRNA gene) further defined the organism as Encephalitozoon hellem . Sequence homology with other eukaryotes was determined using a BLASTN search from the NCBI GenBank database. The finch isolate sequences showed greater than 99% homology with those of previously reported human and avian isolates.  相似文献   

4.
A 12-day-old nestling Gouldian finch (Erythrura [Chloebia] gouldiae) was presented for investigation of a mortality problem in nestling finches raised by Bengalese finch foster parents. On histological examination, large numbers of spores consistent with a microsporidian organism were present within the small intestinal mucosa. Electron microscopy and molecular studies (sequencing the 5' end of the ssu rRNA gene) further defined the organism as Encephalitozoon hellem. Sequence homology with other eukaryotes was determined using a BLASTN search from the NCBI GenBank database. The finch isolate sequences showed greater than 99% homology with those of previously reported human and avian isolates.  相似文献   

5.
Trichomoniasis is a sexually transmitted disease of cattle and a large bowel diarrheal disease of cats caused by Tritrichomonas foetus. Recently, other species of trichomonads have been identified from the prepuce of virgin bulls. It is not clear whether these non-T. foetus isolates are common (nor) or is it clear whether they are also present on the prepuce of breeding bulls. To answer these questions, we first developed an immunofluorescent assay (IFA) with T. foetus-specific monoclonal antibodies for comparison with a T. foetus-specific PCR assay. Results showed that all PCR positive isolates were also IFA positive, whether the isolates were from cats or cattle and PCR negative isolates were IFA negative. Bovine non-T. foetus (non-Tf) trichomonad isolates were detected by both assays in 14 virgin bulls, 10 breeding bulls, 21 bulls of undetermined breeding status (presumably breeding bulls) and 2 cows. These isolates from virgin bulls were mostly Tetratrichomonas spp. whereas the non-Tf isolates from most breeding bulls and the two cows were Pentatrichomonas hominis. All T. foetus isolates were from breeding bulls or bulls of undetermined breeding status. This IFA test which discriminates between T. foetus and non-Tf may be useful as a diagnostic assay, since no effective legal treatment is available, bulls positive for T. foetus are culled. With increasing reports of T. foetus large bowel infection in cats, these monoclonal antibodies may also be useful for diagnosis of feline infection. Since two isolates of non-Tf trichomonads were obtained vaginas of breeding cows, it may be that these parasites are sexually transmitted like pathogenic T. foetus.  相似文献   

6.
Three different parasites of the phylum Parabasala (Tritrichomonas foetus, Trichomitus rotunda and Tetratrichomonas buttreyi) have been described in pigs. In a previous study (Mostegl et al., 2011) approximately 47% of 91 paraffin wax-embedded intestinal samples of pigs which were Trichomonas-positive by in situ hybridization using a probe with a broad reactivity spectrum contained other species than T. foetus. Out of these, intestinal trichomonads from three pigs (pigs 1-3) were further analyzed by gene sequencing of a part of the 18S ribosomal RNA (rRNA) gene using primer walking. Subsequently, the partial sequences achieved by the different primer pairs were combined to a sequence of about 1000 bp for each trichomonad. In all three pigs unique sequences were acquired which showed only moderate similarities to sequences available in the GenBank. Alignments and the BLAST analysis showed a high degree of homology between sequences of trichomonads from pig 1 and pig 3 with only 1% difference. These sequences were found to be 92% similar to Hypotrichomonas acosta, a trichomonad isolated from squamate reptiles. The trichomonad sequence detected in the intestine of pig 2 showed about 10% nucleotide differences compared to pigs 1 and 3. This sequence was 97% similar to two Trichomitus batrachorum (a frog symbiont) sequences. A phylogenetic analysis using the neighbor-joining and maximum likelihood methods supported the data of the BLAST analysis. These results suggest the presence of at least two as yet undescribed trichomonad species in the intestinal contents of pigs.  相似文献   

7.
对21株分离自河南及山西地区的鸡杆菌的16SrRNA基因序列进行研究,以此分析分离株的进化关系并确定其在鸡杆菌属中所属的具体种。采用PCR方法扩增其16SrRNA基因序列,然后克隆测序。用DNAStar软件对21个菌株的序列及GenBank中已公布的鸡杆菌属相关菌株序列进行同源性比较,结果发现21株分离株之间的核苷酸序列同源性为96.0oA~100%,同鸭源鸡杆菌F279(Gallibacteriuman atis F279)(AF228002)的同源性为95.3%~99.3%,同输卵管炎鸡杆菌F150(Gallibacterium salpingitidis F150)(EU424000)的同源性为88.3%~91.5%,同虎皮鹦鹉鸡杆菌F450(GallibacteriummelopsittaciF450)(EU339196)的同源性为90.3%~93.3%,同海藻糖发酵鸡杆菌52-S3-90(Gallibacteriumtrehalosi fermentans52-s3—90)(EU339199)的同源性为88.2%~91.4%,同多杀性巴氏杆菌CCUG179(P.multocida CCUG17977)(AF294411)的同源性为85.5%~88.8%,对21株细菌的序列同以上菌株的16SrRNA基因序列进行遗传进化树分析,显示21株细菌同鸭源鸡杆菌F279(AF228002)构成一个单独的大分支。结果表明,所有分离株均属于鸭源鸡杆菌,首次大量报道了来源于河南、山西省不同地区的鸡杆菌的16SrRNA基因序列,为鸡杆菌分类的研究提供了参考。  相似文献   

8.
鸡源致病性奇异变形杆菌的分离鉴定与遗传进化分析   总被引:2,自引:2,他引:0  
徐睿  李颜桃 《中国畜牧兽医》2018,45(9):2550-2558
为了解鸡源奇异变形杆菌的耐药情况、致病力和遗传特征,本试验从凉山地区分离得到2株细菌(YLF1、WS),通过培养特征、镜检特征和16S rRNA序列测定对分离菌进行鉴定及致病性试验;采用(K-B)法检测分离菌对14种常用抗生素(包括β-内酰胺类、头孢烯类、氨基糖苷类、四环素类、氟喹诺酮类、大环内酯类)的敏感性;并与GenBank中公布的21种不同来源的变形杆菌16S rRNA基因序列进行遗传进化分析。结果表明,YLF1、WS菌株均具有迁徙性和β-溶血生长特征,镜检为革兰氏阴性长短不一的杆菌或球菌,经16S rRNA基因鉴定与GenBank中奇异变形杆菌同源性均在99%以上,YLF1、WS菌株确定为奇异变形杆菌,均表现为多重耐药,耐药率分别为78.6%(11/14)和71.4%(10/14);雏鸡致死率均为80%;YLF1、WS菌株与日本人体分离株、中国新疆黄牛分离株和中国广东土壤分离株同源性最高,达99.9%;与来自中国河南、中国新疆及印度的鸡源奇异变形杆菌同源性较高(98.9%~99.3%),遗传关系密切。表明凉山地区鸡群中存在奇异变形杆菌感染,分离株有较高的致病力和较强的耐药性,也提示分离菌可能来源于环境、感染鸡或其他动物,同时存在人畜共患的潜在危险。  相似文献   

9.
2010年8月一批进口入境的裸鼠在隔离期间发生了疑似国外文献报道的过度角化性皮炎,为了确诊该病及鉴定该病的病原,本研究从患病裸鼠皮肤组织分离到一株革兰氏阳性杆菌。细菌纯化后经Biolog自动生物鉴定仪系统初步鉴定为牛棒状杆菌(C.bovis);提取细菌基因组,PCR扩增16S rRNA基因,测序结果经比对与GenBank中的C.bovis同源性在99%以上;培养物感染裸鼠没有出现临床症状,但组织学检查显示,感染裸鼠表皮棘皮层增厚,表现出轻微的C.bovis感染特有的棘皮症。由此可以确认这次入境裸鼠暴发的疫病为过度角化症,病原为C.bovis。本研究首次报道了在我国实验动物设施暴发的裸鼠过度角化症,提示裸鼠感染C.bovis导致的过度角化症是实验动物质量监测中不可忽视的传染病。  相似文献   

10.
Increased mortality (1.5% per week) and low egg production (5-10% lower than normal) were observed in a flock of domestic breeding Pekin ducks (Anas platyrhynchos). At necropsy, salpingitis and peritonitis were the most significant findings. Histologically, there was accumulation of necrotic debris in the lumen of the oviduct. Numerous bacteria and trichomonads were observed histologically in the lumen of the vagina and occasionally in the shell gland. Escherichia coli and a trichomonad were isolated from the oviduct. The trichomonads were oval (6-8 microm long, 4.5-6 microm wide) and had 4 anterior flagella and an undulating membrane extending over the entire length of the body, finishing in a long posterior flagellum. Morphology was consistent with trichomonads of the genus Tetratrichomonas. Comparative sequence analysis of the 5.8S ribosomal RNA gene and the flanking internal transcribed space regions of the trichomonad isolate did not closely match with available sequences of the same region of other trichomonadid protozoa.  相似文献   

11.
The prevalence of hematozoan infections (Hepatozoon canis and Babesia sp., particularly Babesia canis vogeli) in canids from Venezuela, Thailand and Spain was studied by amplification and sequencing of the 18S rRNA gene. H. canis infections caused simultaneously by two different isolates were confirmed by RFLP analysis in samples from all the geographic regions studied. In Venezuela, blood samples from 134 dogs were surveyed. Babesia infections were found in 2.24% of the dogs. Comparison of sequences of the 18S rRNA gene indicated that protozoan isolates were genetically identical to B. canis vogeli from Japan and Brazil. H. canis infected 44.77 per cent of the dogs. A representative sample of Venezuelan H. canis isolates (21.6% of PCR-positives) was sequenced. Many of them showed 18S rRNA gene sequences identical to H. canis Spain 2, albeit two less frequent genotypes were found in the sample studied. In Thailand, 20 dogs were analyzed. No infections caused by Babesia were diagnosed, whereas 30 per cent of the dogs were positive to hematozoan infection. Two protozoa isolates showing 99.7-100% identity to H. canis Spain 2 were found. In Spain, 250 dogs were studied. B. canis vogeli infected 0.01% of the animals. The sequence of the 18S rRNA gene in Spanish isolates of this protozoa was closely related to those previously deposited in GenBank (> 99% identity). Finally, 20 red foxes were screened for hematozoans employing semi-nested PCR and primers designed to detect Babesia/Theileria. Fifty percent of the foxes were positive to Theileria annae. In addition, it was found that the PCR assay was able as well to detect Hepatozoon infections. Thirty five percent of the foxes were infected with two different H. canis isolates showing 99.8-100% identity to Curupira 1 from Brazil.  相似文献   

12.
副猪嗜血杆菌16S rRNA基因的克隆及序列分析   总被引:2,自引:1,他引:1  
本研究旨在从分子水平对副猪嗜血杆菌湖南分离株进行鉴定,并用16S rRNA序列分析不同血型副猪嗜血杆菌之间的遗传关系。利用PCR扩增副猪嗜血杆菌的16S rRNA,应用ClustalX 1.81程序对序列进行比对,再用Phylip 3.67程序MP法和Mage 4.0程序NJ法绘制种系发育树,并用Puzzle 5.2程序构建最大似然树,同时利用DNAStar 5.0中的Megalign程序进行同源性分析。结果显示,所获得的16S rRNA序列长度均为783 bp,湖南分离株与已知5型副猪嗜血杆菌位于同一分枝。结果表明,湖南分离株属于5型副猪嗜血杆菌,为副猪嗜血杆菌的分子流行病学和其相关疾病的诊断奠定基础。  相似文献   

13.
Tritrichomonosis is a widespread, economically important venereal disease caused by Tritrichomonas foetus. The traditional diagnosis of this disease, which causes infertility and abortion in cattle, is based on the culture of the parasite. This process is time consuming, has low sensitivity, and is prone to contamination with intestinal or coprophilic trichomonadid protozoa, resulting in false positive diagnostics of T. foetus. In order to avoid the shortcomings of the traditional method, we developed a simple PCR assay based on TFR3 and TFR4 primers, which does not require parasite culturing. The sensitivity of the PCR assay resulted comparable to that of the classical method, being able to detect as few as five T. foetus parasites. In addition the method is highly specific. The analysis of preputial fluid washing samples showed that 58 out of 203 samples were positive by both, the PCR and the culture method (+/+), 9 samples were positive by PCR and negative by the traditional method (+/-) and only one sample resulted negative by PCR and negative by culture (-/+). The samples for the PCR assay can be stored for a week at 4 degrees C or 72h at room temperature. In summary, our study demonstrated that the PCR assay is an effective method for the diagnosis of T. foetus from preputial samples, and that it compares advantageously to the classical method.  相似文献   

14.
In August 2002, bovine anaplasmosis and concurrent infections with Mycoplasma sp. and piroplasms were reported in a cattle herd in an alpine region of Switzerland. The piroplasms were identified by PCR/sequencing of part of the 18S rRNA gene as Babesia bigemina and Theileria of the buffeli/sergenti/orientalis-complex, which have never been diagnosed in Switzerland before. The B. bigemina isolate was genetically characterised at two loci and compared with isolates from Italy, Spain, Turkey, Kenya and Mexico. Analysis of the internal transcribed spacer 2 (ITS2) of the rRNA genes revealed high polymorphism not only among the isolates but even within the isolates, and the presence of two types of the ITS2 in every isolate was confirmed. A dendrogram based on ITS2 sequences showed that the Swiss isolate was most closely related to a Spanish isolate but no sequences of the isolate from Switzerland were identical to any of the other isolates. The isolate from Italy was not positioned in the same cluster as the Swiss and the Spanish isolate. This had been anticipated as the nearest known endemic area of B. bigemina in Central Italy. Sequence analysis of the rhoptry-associated protein-1c gene (rap1c) confirmed the similarity of the Swiss and Spanish isolate. Hence, our molecular analyses of the Swiss B. bigemina isolate did not unequivocally track its geographical origin and the way of introduction remains obscure.  相似文献   

15.
A common quail (Coturnix coturnix) from a private keeping died unexpectedly and showed a moderate lymphocytic infiltration of the colonic mucosa associated with numerous protozoa-like objects at the pathological examination. These organisms were further identified using chromogenic in situ hybridization (ISH) and gene sequencing. ISH was performed on paraffin embedded tissue sections and produced a positive signal using a probe specific for the 18S ribosomal RNA (rRNA) gene of the order Trichomonadida, but remained negative with probes specific for the 18S rRNA gene of the common bird parasites Histomonas meleagridis, Tetratrichomonas gallinarum or Trichomonas gallinae. The trichomonads were found on the mucosal surface, inside the crypts and also immigrating into the lamina propria mucosae. DNA was extracted from the paraffin embedded tissue and the entire 18S rRNA gene, ITS-1 region, 5.8S rRNA gene, ITS-2 region and a part of the 28S rRNA gene were sequenced using primer walking. The acquired sequence showed 95% homology with Tritrichomonas foetus, a trichomonad never described in birds. A phylogenetic analysis of a part of the 18S rRNA gene or of the ITS-1, 5.8S and ITS-2 region clearly placed this nucleotide sequence within the family of Tritrichomonadidae. Therefore, the authors propose the detection of a putative new Tritrichomonas sp. in the intestine of a common quail.  相似文献   

16.
为研究上海地区犬感染细小病毒(Canine parvovirus,Cpv)的基因特点和基因型,参考GenBank上细小病毒3个基因型的全基因设计6对扩增引物进行PCR,分段扩增出目标片段,克隆于T载体上,测定序列并拼接,用MEGA软件、NJ法构建进化树。结果显示,犬细小病毒全基因为4758bp,命名为CPV-SH.提交到GenBank上的序列号为FJ792845,与GenBank中4神基因型爽细小病毒的VP2基因核苷酸序列同源性比较发现,CPV-SH克隆与2a亚型犬细小病毒核苷酸同源性为最高99.7%,与2型、2b亚型。2e亚型的同源性分别为98.8%、99.5%.99.5%。CPV-SH属于2a亚型犬细小病毒,与国内北京分离株CPV/BJ082亲缘关系最近,同源性为99.9%。  相似文献   

17.
The phylogenetic relationships of five isolates of Pasteurella multocida serotype B:2 belonging to buffalo, cattle, pig, sheep and goat were investigated by comparative sequence analysis of 16S rRNA gene. The 1468bp fragment of 16S rRNA gene sequence comparison showed that the isolates of cattle (PM75), pig (PM49) and sheep (PM82) shared 99.9% homology with the buffalo isolate (vaccine strain P52) whereas, the goat isolate (PM86) shared 99.8% homology with the vaccine strain. The 16S rRNA gene sequences of these isolates were also found monophyletic with type B reference strain NCTC 10323 of P. multocida subsp. multocida. The present study indicated the close relationships of haemorrhagic septicaemia causing P. multocida serotype B:2 isolates of buffalo and cattle with other uncommon hosts (pig, sheep and goat).  相似文献   

18.
In pigs, three different trichomonad species (Tritrichomonas foetus, Tetratrichomonas buttreyi and Tritrichomonas rotunda) have been described as commensals in the large intestine. The aim of this study was to gain further knowledge on the prevalence and pathogenicity of trichomonads in pigs by using a morphology-based approach. Chromogenic in situ hybridization (ISH) is a technique which allows direct localization of the protozoa in the intestinal tissue and correlation of the infection with pathologic changes. In the present study paraffin-wax embedded colon and ileum samples of 192 pigs were analyzed with this method. Using a probe specific for all known members of the order Trichomonadida (OT) 100 of the 192 pigs were tested positive. Thereof, about 10% showed moderate to high-grade parasitic load with trichomonads invading the lamina propria. Partial 18S ribosomal RNA gene sequencing of six of those animals showed a 100% sequence identity with T. foetus sequences. The majority of these animals were also tested positive for other enteropathogenic agents, such as Brachyspira sp., Lawsonia intracellularis, Escherichia coli, and porcine circovirus type 2. All OT-positive samples were further examined with another probe complementary to all known Tritrichomonas species sequences including T. foetus, T. augusta, T. mobilensis and T. nonconforma resulting in only 48 positives. These results suggest that T. foetus may not only be considered as an intestinal commensal but rather a facultative pathogen of pigs with a tendency for tissue invasion in the presence of other agents. Furthermore, the existence of other - yet to be identified - trichomonad species in the colon of pigs was shown.  相似文献   

19.
猪圆环病毒2型云南株分离鉴定及ORF2序列分析   总被引:1,自引:1,他引:0  
本研究根据GenBank中已经发表的猪圆环病毒2型基因序列,设计了2对PCV2特异性引物,从疑似断奶仔猪多系统衰竭综合征(postweaning multisystemic wasting syndrome,PMWS)感染病例中检测出3株云南省PCV2流行株,通过ve-ro细胞分离病毒,并用透射电子显微镜观察到了约17nm的病毒样粒子的存在。经同源性比较分析,3个分离株之间核苷酸同源性为99.5%~99.8%,与甘肃省PCV2分离株核苷酸同源性最低(90.7%),浙江省分离株核苷酸同源性最高(99.7%),与南美洲分离株核苷酸同源性最低(92.0%),瑞典分离株核苷酸同源性最高(99.4%),这可能与云南省猪种引进有关。  相似文献   

20.
The immune response in cattle infected with Tritrichomonas foetus   总被引:4,自引:0,他引:4  
Holando-Argentina calves (males and females) were experimentally infected with Tritrichomonas foetus var. Belfast (T. foetus) by introducing 10(7) protozoa into the preputial and vaginal cavities, in order to analyse the course of the immune response to infection. Samples of serum, vaginal mucus and preputial secretion were taken periodically and assayed by means of microagglutination of living protozoa. The serum antibody titre, which averaged 32 before infection and was equivalent to titres in a non-infected group, increased to 512 in the heifers 11 weeks later and to 128 in the bulls 4 months post-infection. Agglutinating antibodies were not detected in the preputial cavity, but heifers showed antibodies in the vaginal mucus and became trichomoniasis free after 4 months. Conversely, genital secretions from the bulls gave rise to positive cultures during the whole period of experimentation. The intradermal sensitivity was checked using a soluble antigen from T. foetus. The diameter of the papula increased up to three times in heifers, while in bulls the results were no different than those from the non-infected group. Serum antibodies were of the IgG2 subclass, while those isolated from vaginal mucus were characterized as IgG1, an opsonizing antibody. Heifers were refractory to challenge infection after 1 year. The poor immune response in bulls is consistent with their role as carriers of T. foetus.  相似文献   

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