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1.
Tritrichomonas foetus is recognized as the causative agent of venereal trichomoniasis in cattle. It is characterized by embryonic and early fetal death and post-coital pyometra, and feline trichomoniasis, manifest as chronic, large bowel diarrhea. Many of the infected cats are less than 2 years old and specific routes of transmission remain unknown. We recently demonstrated that feline isolates of T. foetus can successfully infect heifers, resulting in pathologic changes similar, but not identical to those previously reported as representative of bovine trichomoniasis. In this study, we experimentally infected six cats less than 1 year of age with a bovine (D-1) isolate of T. foetus and one cat with a feline (AUTf-1) isolate of T. foetus. Within 2 weeks, the cat infected with the feline (AUTf-1) isolate was culture positive for trichomonads in weekly fecal samples. At the end of 5 weeks, only one cat infected with the bovine (D-1) isolate was fecal culture positive for trichomonads. At necropsy, the intestine of each cat was removed and divided into five sections (ileum, cecum, anterior, medial and posterior colon). Contents from each section were collected and cultured. The cat infected with the feline (AUTf-1) isolate was culture positive in the ileum, cecum, medial and posterior colon. Two cats infected with the bovine (D-1) isolate were culture positive in the cecum only. Additionally, each intestinal section was submitted to a pathologist for histopathological examination. The combined results indicate that there are demonstrable differences between the feline (AUTf-1) and bovine (D-1) isolates regarding their infectivity in cats.  相似文献   

2.
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   

3.
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   

4.
旨在进一步鉴定从1例长期慢性腹泻猫粪便中新分离到的1株毛滴虫，分别对其进行了分离与体外培养、形态学观察及18S rRNA基因序列相似性分析。形态学观察结果显示，分离株毛滴虫呈梨形或纺锤形，且具有3根前鞭毛和1根后鞭毛，为胎儿三毛滴虫形态结构。18S rRNA基因序列与GenBank中三毛滴虫基因序列比对及系统进化树结果显示，分离的猫源毛滴虫序列与胎儿三毛滴虫MH400076.1处于同一分支，且相似性达到了99%。综合判定，从患有长期慢性腹泻猫的粪便中分离到的毛滴虫为胎儿三毛滴虫。  相似文献   

5.
To further identify a new strain of Trichomonad isolated from the feces of a cat with chronic diarrhea, isolation and cultivation, morphological observation and gene homology analysis of 18S rRNA of the Trichomonad were accomplished in this study. Morphological observation showed that the Trichomonas was shaped pear or spindle, with 3 anterior flagella and 1 posterior flagella. The results of phylogenetic tree construction showed that Trichomonas isolated in this study is Trichomonas foetus, which is in the same evolutionary branch and is closely related to the sequence MH400076.1 in GenBank with 99% sequence similarity. Based on the above identification results, this Trichomonas isolated from cats with long-term chronic diarrhea is T. foetus.  相似文献   

6.
To explore the prevalence of Theileria equi (T.equi) infection in horse in Guizhou province, the antibody level and 18S rRNA gene were detected from blood samples of Guizhou pony, Southwest horse and Yili horse using competitive ELISA and PCR methods.Giemsa-stained blood smear was prepared to observe T.equi in red blood cells.Intact protozoans of T.equi were observed in red blood cells of horses at Giemsa-stained slide smears with a detection rate of 12.5%.The 18S rRNA gene fragment of T.equi was detected in Guizhou pony, Southwest horse and Yili horse, and the consistent rates with the known nucleotide sequence were 97% to 100%.The PCR result indicated that the positive rates of T.equi in Guizhou pony (76.62%) and Yili horse (73.81%) were similar, which were higher than that in Southwest horse (33.33%).Furthermore, the antibody levels against T.equi in Guizhou pony (24.68%) and Southwest horse (12.12%) were lower than that in Yili horse (31.71%).A weak correlation between the antibody level and the blood physicochemical indexes was calculated from Guizhou pony and Southwest horse, including weak positive correlations with neutrophils numbers, gamma-glutamyl transferase and creatine kinase levels, and weak negative correlations with the numbers of red blood cell, white blood cell, platelet and lymphocyte and contents of hemoglobin.It suggested that a higher proportion of T.equi infection present in three herds.  相似文献   

7.
3个马群感染马泰勒虫的分子病原学调查   总被引：1，自引：0，他引：1  
试验采用显微镜观察、PCR和竞争性酶联免疫吸附试验(competitive enzyme-linked immunosorbentassay,cELISA)等方法对贵州矮马、西南马和伊犁马的马泰勒虫病的感染状况进行研究。结果显示,从32份新鲜的血液涂片中,观察到形态完整的马泰勒虫(Theileria equi)虫体,检出率12.5%。从贵州矮马、西南马及伊犁马3个马群血液总DNA中都检测到马泰勒虫的18S rRNA基因片段,与已知序列的同源性为97%~100%;相比之下,贵州矮马与伊犁马的阳性率相近,分别为76.62%和73.81%,西南马较低,仅为33.33%。另外,经cELISA检测,与伊犁马(31.71%)相比,贵州矮马和西南马血液中抗马泰勒虫抗体的阳性率较低,分别为24.68%和12.12%,并与两个马群的血液理化指标存在一定的联系:与中性细胞数量、γ-谷氨酰转移酶和肌酸激酶的含量呈弱正相关;与红细胞、白细胞、血小板、淋巴细胞数量及血红蛋白含量呈弱负相关。这些研究结果提示3个马群中均存在较高比例的马泰勒虫感染。  相似文献   

8.
All the calves born (116) into 3 Maasai cattle herds in the Trans-Mara Division of Kenya, between August 1978 and October 1979, were recruited into a monthly health study which concentrated on theileriosis. Twenty-two of the calves died before they were 6 months of age, but the mortality only increased to 25% by the time the calves reached 18 months of age. The mean birth weight of calves was 17.5 kg while at 190 days post-birth the mean weight was 53.4 kg. The main causes of mortality were starvation (7.8%), neonatal diarrhoea (2.6%), chronic indigestion (2.6%) and theileriosis (2.6%) due to Theileria parva and T. mutans infections. The calves were infected with ticks from birth (mostly Rhipicephalus appendiculatus and Amblyomma spp.) and the first Theileria schizonts were detected on Day 17 post birth and reached a maximum of 18.4% of calves in the 11th week post-birth. Seasonal peaks of macroschizont incidence occurred in February and July. All calves had patent Theileria piroplasm infections by the time they were 5 months old and 44% had shown patent Theileria macroschizont infections by 6–7 months of age. Generally low parasitosis of Theileria piroplasms and schizonts occurred. Serology using the indirect fluorescent antibody test showed a high proportion of calves received antibodies against T. mutans and T. parva from their dams by way of colostrum. The majority of calves also had active antibody responses against T. mutans and T. parva by the time they were 6 months of age. There was a correlation between the pre-patent period of piroplasms and active antibody responses to T. mutans and between the prepatent period of schizonts and an antibody response to T. parva. Eighteen older calves developed T. velifera infections. “Turning sickness” due to Theileria infection in the brain was detected in older cattle. Other blood parasites such as Trypanosoma vivax, T. congolense, Anaplasma marginale and Babesia bigemina occurred at patent levels at a lower incidence than Theileria spp. and did not cause disease problems in the calves. The calf population was highly resistant to theileriosis since they had a 100% morbidity, but only 2.6% mortality. Theileria infections would appear to have an important effect on the growth of calves but this and many aspects of the epidemiology of theileriosis in the area required more intensive sampling.  相似文献   

9.
The objective of this work was to study cellular changes in the epithelium of the mare’s oviduct. Oviductal samples were taken from mares at different reproductive stages for optical microscopy and Hoechst 33258 staining. Glandular-like structures were observed in 100% of the oviducts. These structures were of the tubular type and were formed by ciliated and nonciliated epithelial cells arranged in a way similar to the epithelial surface. The amount of structures decreased progressively from the ampulla to the isthmus, but did not change through the different reproductive stages. Histological changes in the epithelium of the oviduct were observed associated with the reproductive stages. In the ampulla, the amount of ciliated cells decreased in the anovulatory phase compared with other reproductive stages. Cords of connective tissue lined by epithelium (trabeculae) and dividing completely the lumen of the oviduct were found in 50% of the oviducts. Epithelial cells projected toward the lumen as large vesicles of cytoplasm, sometimes containing a nucleus. The amount of cells presenting nuclear protrusion varied throughout the oviduct, with highest incidence in the ampulla, decreasing progressively toward the isthmus (P < .05). In addition, nuclear protrusions were higher in number during the anovulatory and luteal phases than in the other reproductive stages (P < .05). These nuclear protruding cells appeared to be extruding from the epithelium and showed no signs of apoptosis based on the histological and fluorescent stains used. The existence of these gland-like structures in the oviductal mucosa should be considered when studying the oviductal physiology in mares.  相似文献   

10.
A study was conducted to determine the incidence of trypanosome infections in cattle in tsetse-free and tsetse-infested zones of the Amhara Region of northwest Ethiopia. A total of six sentinel herds were established and the cattle observed during a period of 8 consecutive months. The prevalence of seropositive cattle was high in both the tsetse-free and tsetse-infested zones. The average monthly incidence of trypanosome infection, determined using molecular diagnostic tools, was 20.9% and 25.7% in the tsetse-free and the tsetse-infested zones, respectively. In the tsetse-free, Trypanosoma vivax was responsible for 90.9% of the cattle trypanosome infections. In the tsetse-infested zone, Trypanosoma congolense and T. vivax contributed almost equally to the trypanosome infections in cattle. Trypanosome infection, regardless of species, resulted in anaemia as evidenced by a significant decrease in the packed cell volume of the infected animal. The outcome of this longitudinal study suggests that control of trypanosomiasis in the Amhara Region cannot be achieved by tsetse control alone. Supplemental measures to include drug therapy and biting fly control are discussed.  相似文献   

11.
旨在探究终末宿主肝环状RNA （circRNAs）在犬弓首蛔虫诱导致病过程中的潜在调控作用。18只6~7周龄的比格犬被平均分为3组（感染后0.5 d组、感染后1 d组和感染后36 d组），每组包括感染和对照各3只，分别于感染后对应的时间点收集肝样品。提取感染和对照组肝的总RNA，利用高通量RNA测序，构建circRNA文库，对差异表达的circRNAs进行分析，并对差异表达circRNAs的亲本基因进行GO注释和KEGG富集分析。随机选取9个差异表达circRNAs进行实时荧光定量PCR验证。结果显示，与对照组相比，在感染后0.5、1和36 d分别有94、103和84个犬肝的差异表达circRNAs。Venn图显示，3个感染阶段没有共同表达的差异circRNAs；GO和KEGG分析显示，差异表达的circRNAs参与了宿主肝免疫与炎症的相关通路，其中差异表达的circRNA novel_circ_0016108、novel_circ_0016184和novel_circ_0027468与犬弓首蛔虫引起的天然免疫相关；novel_circ_0002212参与了犬弓首蛔虫引起的肝炎症反应；novel_circ_0002212和novel_circ_0019907在宿主肝抵抗犬弓首蛔虫侵袭的过程中发挥作用。RT-qPCR验证结果显示大多数差异表达的circRNAs与高通量测序结果一致。结果表明，肝circRNAs在犬弓首蛔虫感染终末宿主的过程中发挥着重要作用，这为进一步探究犬弓首蛔虫与宿主之间的相互作用提供了新的信息，并且也为促进疾病干预措施的制定提供参考。  相似文献   

12.
Theileria parva is the causative agent of a lethal tick-borne disease of cattle occurring in eastern, central and southern Africa. Variations in the sensitivity of the serological and molecular tests with seasonal vector occurrence and discrepancies between low PCR prevalence and high T. parva vector density are a setback to estimate true prevalences. Therefore, the objectives of the present studies were to evaluate (1) the sensitivity of three serological tests (IFAT, ELISA and SELISA) and one molecular test (PCR) in the diagnosis of chronic T. parva infections in four different agro-ecological zones of Rwanda and (2) the effect of tick challenge and animal's age on the sensitivity of PCR. Blood samples from 635 bovines were collected in four agro-ecological zones of Rwanda. All sera were screened using the IFAT, ELISA, SELISA and PCR. The binary results of the four diagnostic tests were introduced separately for each agro-ecological zone in a Bayesian model to estimate the prevalence of T. parva infections and the sensitivity of the four diagnostic tests. All test specificities were set to 100%. The estimated T. parva prevalence was much higher (83–85%) than estimations based on single diagnostic tests. The estimated sensitivity of serological tests was relatively constant and ranged from 57 to 75% in the various areas. The sensitivity of PCR showed more pronounced variations, ranging from 66% in the low T. parva transmission (high land) zones compared to 24% in the highly vector infested (low land) zones. Calves and adult cattle (n = 194) were also sampled in regularly and irregularly dipped herds in the low land region. The apparent T. parva prevalence detected by PCR was significantly higher in calves than in adult cattle and in herds regularly treated with acaricides, while no significant differences were found with IFAT. The conditional probability that a sample was positive at PCR while it was positive at IFAT was significantly lower in adults. The implication of these findings in the use of diagnostic assays for epidemiological studies is discussed.  相似文献   

13.
为了解吕氏泰勒虫在中国不同地区山羊和绵羊中的流行情况,本研究应用基于吕氏泰勒虫18S rRNA基因位点的PCR检测方法,对采自中国河南、甘肃、陕西、山西、贵州、云南、新疆7个地区的281份羊血液样品进行检测,并对阳性样品测序以进行序列分析。结果显示,羊吕氏泰勒虫总感染率为35.23%（99/281）。不同采样点羊吕氏泰勒虫感染率差异极显著（P<0.01）,其中河南省羊吕氏泰勒虫感染率最高（98%,49/50）,新疆最低（0）。绵羊和山羊吕氏泰勒虫感染率分别为51.67%（31/60）和30.77%（68/221）,差异极显著（P<0.01）;放牧羊吕氏泰勒虫感染率（41.55%,86/207）极显著高于舍饲羊（17.57%,13/74）（P<0.01）;羊吕氏泰勒虫感染率在春、夏、秋及冬四季分别为56.00%（28/50）、42.75%（59/138）、9.43%（5/53）和17.50%（7/40）,差异极显著（P<0.01）;≥ 12月龄和<12月龄羊吕氏泰勒虫感染率分别为33.50%（67/200）和39.51%（32/81）,差异不显著（P>0.05）。此外,遗传进化分析表明,本研究获得的羊吕氏泰勒虫分离株与中国流行的吕氏泰勒虫分离株同源性高达99.60%以上,且位于同一分支上。本研究为进一步了解中国不同地区羊吕氏泰勒虫的流行现状及分布提供了重要参考依据。  相似文献   

14.
The Brazilian Pantanal is a 138 000 km2 tropical seasonal wetland located in the center of South America bordering Bolivia and Paraguay. The Pantanal contains approximately 1100 cattle ranches, 3 million cattle, 49 000 horses and a unique diversity of wildlife. Cattle ranching is the most important economic activity in the Pantanal. This study explores the direct financial impacts of the adoption of seven treatment strategies for the control of Trypanosoma evansi in the Brazilian Pantanal. T. evansi adversely affects the health of the horse population in the region. Horses are indispensable to the cattle ranching industry in the Pantanal. Estimated costs include risk of infection, costs of diagnosis, alternative treatments, collecting animals for treatment, and costs of animal losses. The estimated total cost of T. evansi to the Pantanal region's cattle ranchers is about US$2.4 million and 6462 horses/yr. Results indicate that one preventive and two curative treatment strategies are financially justifiable. The best available technology for the treatment of T. evansi from an economic perspective is a curative treatment employed year-round. This treatment represents an annual net benefit of more than US$2 million or US$1845/ranch and spares about 5783 horses. It represents an annual net benefit of over US$200 000 and 600 horses relative to the currently most widely adopted strategy.  相似文献   

15.
Two studies (one pilot and one cross-sectional) were conducted in the two main livestock-rearing areas of Costa Rica using an improved method (In-Pouch TF) for the detection of Trichomonas foetus infection in bulls. Herd prevalence rates of 6.7% (6/98) and 15.9% (10/63), and bull prevalence rates of 3.9% (6/153) and 6.2% (14/225) were found in the pilot and cross-sectional studies, respectively. Adjusted prevalences in the cross-sectional study were 18.4% and 7.2% for aarms and bulls, respectively. Breed (Bos taurus) and age (over 4 years) were the main risk factors identified using random-effects logistics regression. The nature of the disease and the high prevalence indicated that trichomoniasis could have a serious economic impact on cattle production in Costa Rica.  相似文献   

16.
The effect of controlled amounts of exercise on the outcome of Trypanosoma evansi infection was studied in groups of swamp buffaloes (Bubalus bubalis) experimentally infected with T. evansi. Daily body temperature, packed cell volume (PCV) and parasitaemia measurements were obtained from each animal for up to 110 days after infection. Exercise did not appear to exacerbate the effect of T. evansi infection in that similar temperature, PCV and parasitaemia profiles were obtained with both exercised and rested animals. Trypanosoma evansi infection, however, had a marked effect on temperature and PCV profiles, both of which could adversely affect an infected animal's work output and work tolerance.  相似文献   

17.
本研究旨在筛选具有抗弓形虫活性的萜类化合物,并进行体外活性评价。对26个萜类化合物进行体外抗弓形虫增殖作用的筛选,采用CCK-8法确定活性化合物对Vero细胞的毒性和安全浓度,Giemsa染色进一步确定对弓形虫的活性,通过细胞免疫荧光、Giemsa染色和生物化学发光法评价活性化合物对弓形虫的体外活性。结果表明,26个萜类化合物中,桧烯对弓形虫有显著的活性,桧烯对RH-2F的IC50为90.76 μg·mL-1,Giemsa染色和细胞免疫荧光的结果表明,桧烯对细胞内的两种弓形虫虫株都有显著的抗增殖作用,并且对弓形虫的入侵有极显著的抑制作用（P<0.001）。综上表明,桧烯对弓形虫的入侵和细胞内增殖具有显著的抑制作用,可作为潜在的抗弓形虫先导化合物。  相似文献   

18.
Theileria sergenti piroplasms were purified from different parasitemia peaks of cattle infected with parasitized erythrocytes or sporozoites during persistent infection. Their activities with monoclonal antibodies 13F5 and C9, which recognize 23 kDa and 32 kDa piroplasm surface proteins, respectively, were analyzed. Antigenic differences were observed among parasites from different parasitemia peaks during persistent infection when cattle were infected with sporozoites. Results of two-dimensional polyacrylamide gel electrophoresis showed that the 23 and 32 kDa proteins were expressed in all samples tested, regardless of their reactivities with the monoclonal antobodies. In contrast, parasites obtained from cattle inoculated with parasitized erythrocytes showed no antigenic alteration over a 2 month observation period. The results suggest that antigenic alteration of T. sergenti during persistent infection is related to whether the parasites proliferate through extraerythorocytic schizont stage in cattle or sporozoite and other sexual stages in tick vector.  相似文献   

19.
Over a period of one year, from February 1979—February 1980, the abomasa of four dairy cows were examined each week for the presence of parasitic nematodes. Based on the identification of adult male worms, Ostertagia ostertagi (94%) and Trichostrongylus axei (75%) were the most prevalent species, and Haemonchus contortus was absent. Total worm burdens varied from zero (one cow) to 100 890. The geometric mean total number was 3011. The geometric mean number of arrested larval stages was 685. Of the adult worm burden, more than 85% consisted of O. ostertagi, about 12% of T. axei the remaining 3% was other species. No relationship could be found between worm burdens and the age of the cow, the weight of the abomasum or the milk yield.

The adult Ostertagia burden was highest in the period July–September. The numbers and the percentages of arrested larvae were highest in winter, lowest in summer. Besides those of O. ostertagi, small numbers of arrested larvae of T. axei were observed from September onwards. Cows from farms with a zero-grazing system had significantly fewer worms than cows from other farms independently of the time of the year.  相似文献   


20.
弓形虫和新孢子虫是两种亲缘关系接近的顶复亚门原虫，二者之间存在一定程度的交叉免疫保护作用，这种作用可能是基于交叉反应抗原产生的。本研究旨在表达并鉴定弓形虫和新孢子虫的交叉反应抗原TgMIC17A，通过将其应用于小鼠的免疫保护试验，评估该抗原对弓形虫和新孢子虫感染产生的交叉免疫保护作用。对TgMIC17A进行基因克隆和原核表达，通过免疫印迹试验鉴定其反应原性和交叉反应性。重组蛋白免疫小鼠后测定血清特异性IgG抗体水平，评价其免疫原性。二免后，分别用1×103个弓形虫Pru速殖子、1.5×107个新孢子虫Nc1速殖子攻虫，对小鼠的体重变化、存活率进行监测，并在攻虫30 d后检测各组存活小鼠的脑荷虫量，评价TgMIC17A重组蛋白免疫小鼠后对弓形虫和新孢子虫的交叉免疫保护效果。结果显示，rTgMIC17A可以被弓形虫和新孢子虫的阳性血清识别，相较于未免疫组小鼠，免疫组小鼠体内可产生高水平特异性IgG抗体(P＜0.01)，且感染弓形虫或新孢子虫的脑荷虫量均显著降低(P＜0.01)。本研究克隆并表达了TgMIC17A，鉴定其为新孢子虫和弓形虫的交叉反应抗原。该抗原可以刺激小鼠产生较好的体液免疫反应，并对弓形虫和新孢子虫的感染产生一定的交叉免疫保护作用，可以为弓形虫和新孢子虫共感染的防治，以及筛选具有交叉免疫保护力的重组疫苗提供可借鉴的研究资料。  相似文献   

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