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1.
实验在大肠杆菌产生的志贺样毒素2型变异体(Shiga-like toxin Ⅱ e,Stx2e)研究的基础上,设计了一对特异性引物,通过优化,建立了以PCR为基础,高效快速检测猪水肿病的PCR试剂盒.该试剂盒扩增的阳性条带为172 bp的特异性DNA片段,最低检出菌体量为120 CFU,在-20℃至少可保存12个月,重复性良好.应用猪水肿病PCR快速检测试剂盒对22份新鲜样本进行了检测,结果显示,其中的5个样本含Stx2e阳性大肠杆菌,PCR检测结果与剖检、细菌学和生化检验结果相一致.  相似文献   

2.
本研究旨在建立一种快速鉴定致猪水肿病大肠埃希菌的多重PCR检测方法.分别针对大肠埃希菌16S rDNA、志贺毒素Stx2e A亚基和菌毛F18ab A亚基保守序列设计合成3对特异性引物,优化多重PCR反应条件,并进行特异性和敏感性检测.结果显示,阳性对照菌株扩增产物大小分别为1 062、733和313 bp.特异性和灵敏性检测结果表明,与肠炎沙门菌、多杀性巴氏杆菌、胸膜肺炎放线杆菌、副猪嗜血杆菌、支气管败血波氏杆菌和猪链球菌等猪常见致病菌均无交叉反应;菌体直接扩增法最低检出量为1 875 CFU.利用建立的多重PCR检测方法对分离收集的128株大肠埃希菌进行鉴定,得到36株致猪水肿病大肠埃希菌,其中30株既有菌毛F18ab又产志贺毒素Stx2e,另外6株仅产志贺毒素Stx2e.结果表明,本试验所建立的多重PCR检测方法对致猪水肿病大肠埃希菌的快速诊断和流行病学调查具有一定的应用价值.  相似文献   

3.
猪传染性胸膜肺炎放线杆菌PCR检测试剂盒的研制   总被引：1，自引：1，他引：0  
根据GenBank中猪传染性胸膜肺炎放线杆菌apxⅣA基因序列,设计了1对引物,通过对PCR反应条件进行优化,研制了检测猪传染性胸膜肺炎放线杆菌的PCR试剂盒。该试剂盒扩增的阳性条带为600 bp,特异性与敏感性结果显示,该PCR检测试剂盒的最低核酸检测量为50 CFU/mL,而对金黄色葡萄球菌、链球菌、多杀性巴氏杆菌、鼠伤寒沙门氏菌、副猪嗜血杆菌、大肠杆菌的扩增结果均为阴性。-20℃至少可保存12个月,且重复性良好。应用该PCR试剂盒对41份临床样本进行了检测,其PCR检测结果与细菌学检测结果相一致。结果表明,猪传染性胸膜肺炎放线杆菌PCR检测试剂盒能够对APP临床样品进行快捷、灵敏、准确的检测。  相似文献   

4.
本试验分别针对志贺样毒素Ⅱ型变异体(SLT-Ⅱe)B亚基和F18ab茼毛fedA亚基保守序列设计2对引物,扩增长度分别为230 bp和510 bp,通过条件优化,建立了一种快速鉴定致猪水肿病大肠杆菌同时确定其致病因子的二重聚合酶链式反应(PCR)检测方法,对阳性扩增产物测序,结果都有很高的保守性.特异性试验和灵敏性试验表明:与其他6种猪常见致病菌(产毒多杀性巴氏杆菌、胸膜肺炎放线杆菌、波氏杆菌、副猪嗜血杆菌、沙门菌和链球菌)无交叉反应,菌体直接扩增法最低检出量为101cfu(D600为0.002).通过该二重PCR检测方法对2004-2006年自猪肺、脑组织中分离的216株大肠杆菌进行鉴定,得到6株致猪水肿病大肠杆菌,其中3株既具有菌毛又产水肿毒素,另外3株仅产水肿毒素;菌毛阳性菌株占毒素阳性菌株的50%.  相似文献   

5.
猪水肿病毒素即Ⅱ型志贺毒素变异体e亚型(Shiga toxin 2e,Stx2e)。采用吖啶橙/溴化乙锭(AO/EB)双荧光染色法和四甲基偶氮唑盐(MTT)比色法,比较了从患水肿病猪粪便样品中分离的28株大肠杆菌所产志贺毒素对Vero细胞的毒性作用。结果显示,MTT比色法检测的细胞比活力与AO/EB染色法检测的正常细胞与早期凋亡细胞比率之和呈正相关。将28株菌株产生的Stx2e作用于Vero细胞,均能抑制Vero细胞的生长,并诱导Vero细胞的凋亡;其中8株病原菌所产Stx2e毒素对Vero细胞的毒性作用强于O157∶H7。这些毒素的毒力差异可能与其A亚基基因的结构变异有关。结果提示,贵州分离的产Stx2e大肠杆菌的毒力存在一定差异,其中部分菌株的毒力作用较强,应加强对养殖场仔猪的保护。  相似文献   

6.
根据GenBank中的牛结核分枝杆菌IS6110的基因片段,设计了1对引物,通过对PCR反应条件进行优化,研制了用于检测牛结核病的PCR试剂盒,该试剂盒扩增的阳性条带为317 bp;敏感性结果显示,该PCR检测试剂盒的最低核酸检测量为1.025 pg/μL;特异性试验表明,仅结核分枝杆菌扩增结果为阳性,副结核分枝杆菌、胸膜肺炎放线杆菌、大肠杆菌、巴氏杆菌、沙门氏菌、金葡萄球菌、链球菌的扩增结果均为阴性。-20 ℃至少可保存12个月,且重复性良好。应用该PCR试剂盒对24份临床样本进行了检测,其PCR检测结果与结核菌素试验检测结果相一致。结果表明,牛结核病PCR检测试剂盒能够对牛结核临床样本进行快捷、灵敏、准确的检测。  相似文献   

7.
水肿病是能由产志贺样毒素型大肠杆菌产生的Stx2e毒素引起的一种细菌传染病,对断奶仔猪有较高的致死率,常造成较大的经济.当前,Stx2e毒素影响病原菌与靶细胞之间的相互作用机制不明确,Stx2e基因缺失株作为后选疫苗的潜力有待确认.本研究中我们利用Red重组系统构建了大肠杆菌1522 (serotype O139:K12:H1)和1525 (serotype O157:H19)的Stx2e基因缺失株,并通过PCR检验,DNA测序手段以及Vero细胞毒性试验在细胞水平加以验证.研究发现,在同样的培养条件下,1522△Stx2e株的生长特性与原型株相比没有差异,其分解发酵糖类和氨基酸的能力也未发生改变,但是相较野生株,Stx2e基因缺失株粘附猪肠上皮细胞IPEC-J2的能力大幅度降低,可达30％.将表达K99菌毛操纵子基因克隆入1522△Stx2e中,该重组菌能够同时表达K99菌毛和自身的F18菌毛基因,且该重组株的粘附IPEC-J2细胞能力相较原型株增强近l倍.  相似文献   

8.
根据乙型肝炎S基因序列,设计套式PCR引物,通过优化建立了以PCR为基础,高效快速检测奶牛乙型肝炎的PCR试剂盒。该试剂盒扩增的阳性条带为500bp、250bp的特异性DNA片段,建立的奶牛HBV病毒套式PCR能检测到初始模板69.8个拷贝的病毒,在-20℃至少可保存12个月,重复性良好,快速、准确、特异。应用奶牛乙型肝炎PCR快速诊断试剂盒对100份奶牛血清样本进行了检测,结果显示,其中的9个样本奶牛乙型肝炎病毒DNA阳性。  相似文献   

9.
为建立猪源产肠毒素性大肠杆菌(ETEC)的快速准确诊断方法,根据Gen Bank收录的ETEC耐热肠毒素(STⅡ)基因序列设计1对特异性引物,采用SYBR GreenⅠ荧光染料建立ETEC荧光定量PCR诊断试剂盒,并验证该检测法的敏感度、特异性、重复性及试剂盒长期保存的稳定性。结果显示:该诊断试剂盒的最低灵敏限度达1.0×101拷贝/μL,特异性强,对羊源、牛源产肠毒素性大肠杆菌基因未检出;用该试剂盒检测猪场分离的149株临床样品,同时与传统的分离培养后普通PCR比较,该方法检出率高;试剂盒于-20℃保存3~6个月对阳性标准品拷贝数无影响。本研究研制的试剂盒在临床检测大肠杆菌比传统检测方法快且结果表明建立的试剂盒适合于ETEC的检测,为该病的快速诊断和防治提供基础。  相似文献   

10.
正猪水肿病是一种肠毒血型大肠杆菌病,常发生于断奶后两周内的仔猪,然而年龄稍大一点的猪也能受到感染。在丹麦,该病由产志贺毒素Stx2e(vero-toxin 2e)的溶血性F18-阳性大肠杆菌引发。丹麦每年通过实验室可诊断出30~50例新病例。全面介绍的两部内容中的第一部分。1临床症状此病的临床症状为眼睑与前额水肿、神经失调以及突发死亡。该病可以通过用预防断奶后仔猪腹泻的相同措施(低蛋白日粮、限  相似文献   

11.
试验选用96头平均体重14.82 kg左右的杜×长×大断奶仔猪,随机分成4组,每组3栏,每栏8头(公母各半)。对照组饲喂基础日粮,试验1、2、3组分别添加1%80目白术、0.2%白术多糖和1%微米白术。试验期30 d。结果表明:在生长性能方面,与对照组相比,1%微米白术添加组可显著提高日增重(P0.05)、降低饲料增重比和腹泻率,而且效果优于1%80目白术组和0.2%白术多糖组,在肠道形态和肠道微生态区系方面,与对照组相比,日粮添加1%80目白术、0.2%白术多糖、1%微米白术均可不同程度的提高十二指肠和空肠的绒毛高度,加深十二指肠和空肠的隐窝深度,并且增加肠道微生态区系的多样性,其中以1%微米白术添加组的效果最佳。  相似文献   

12.
Sissay, M.M., Uggla, A. and Waller, P.J., XXXX. Prevalence and seasonal incidence of nematode parasites and fluke infections of sheep and goats in eastern Ethiopia. Tropical Animal Health and Production, XXXX. A 2-year abattoir survey was carried out to determine the prevalence, abundance and seasonal incidence of gastro-intestinal (GI) nematodes and trematodes (flukes) of sheep and goats in the semi-arid zone of eastern Ethiopia. During May 2003 to April 2005, viscera including liver, lungs and GI tracts were collected from 655 sheep and 632 goats slaughtered at 4 abattoirs located in the towns of Haramaya, Harar, Dire Dawa and Jijiga in eastern Ethiopia. All animals were raised in the farming areas located within the community boundaries for each town. Collected materials were transported within 24 h to the parasitology laboratory of Haramaya University for immediate processing. Thirteen species belonging to 9 genera of GI nematodes (Haemonchus contortus, Trichostrongylus axei, T. colubriformis, T. vitrinus, Nematodirus filicollis, N. spathiger, Oesophagostomum columbianum, O. venulosum, Strongyloides papillosus, Bunostomum trigonocephalum, Trichuris ovis, Cooperia curticei and Chabertia ovina), and 4 species belonging to 3 genera of trematodes (Fasciola hepatica, F. gigantica, Paramphistomum {Calicohoron} microbothrium and Dicrocoelium dendriticum) were recorded in both sheep and goats. All animals in this investigation were infected with multiple species to varying degrees. The mean burdens of adult nematodes were generally moderate in both sheep and goats and showed patterns of seasonal abundance that corresponded with the bi-modal annual rainfall pattern, with highest burdens around the middle of the rainy season. In both sheep and goats there were significant differences in the mean worm burdens and abundance of the different nematode species between the four geographic locations, with worm burdens in the Haramaya and Harar areas greater than those observed in the Dire Dawa and Jijiga locations. Similar seasonal variations were also observed in the prevalence of flukes. But there were no significant differences in the prevalence of each fluke species between the four locations. Overall, the results showed that Haemonchus, Trichostrongylus, Nematodirus, Oesophagostomum, Fasciola and Paramphistomum species were the most abundant helminth parasites of sheep and goats in eastern Ethiopia.  相似文献   

13.
1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.  相似文献   

14.
Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.  相似文献   

15.
Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.  相似文献   

16.
Genetic variations in chromosome Y are enabling researchers to identify paternal lineages, which are informative for introgressions and migrations. In this study, the male‐specific region markers, sex‐determining region‐Y (SRY), amelogenin (AMELY) and zinc finger (ZFY) were analysed in seven Turkish native goat breeds, Angora, Kilis, Hair, Honaml?, Norduz, Gürcü and Abaza. A SNP in the ZFY gene defined a new haplotype Y2C. All domestic haplogroups originate from Capra aegagrus, while the finding of Y1A, Y1B, Y2A and Y2C in 32, 4, 126 and 2 Turkish domestic goats, respectively, appears to indicate a predomestic origin of the major haplotypes. The occurrence of four haplotypes in the Hair goat and, in contrast, a frequency of 96% of Y1A in the Kilis breed illustrate that Y‐chromosomal variants have a more breed‐dependent distribution than mitochondrial or autosomal DNA. This probably reflects male founder effects, but a role in adaptation cannot be excluded.  相似文献   

17.
The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.  相似文献   

18.
The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.  相似文献   

19.
The purpose of this study was to determine the frequency of different tumor types within a large cohort of cats with intracranial neoplasia and to attempt to correlate signalment, tumor size and location, and survival time for each tumor. Medical records of 160 cats with confirmed intracranial neoplasia evaluated between 1985 and 2001 were reviewed. Parameters evaluated included age, sex, breed, FeLV/FIV status, clinical signs, duration of signs, number of tumors, tumor location(s), imaging results, treatment, survival times, and histopathologic diagnosis. Most of the cats were older (11.3 +/- 3.8 years). Primary tumors accounted for 70.6% of cases. Metastasis and direct extension of secondary tumors accounted for only 5.6 and 3.8% of cases, respectively. Twelve cats (7.5%) had 2 or more discrete tumors of the same type, whereas 16 cats (10.0%) had 2 different types of intracranial tumors. The most common tumor types were meningioma (n = 93, 58.1%), lymphoma (n = 23, 14.4%), pituitary tumors (n = 14, 8.8%), and gliomas (n = 12, 7.5%). The most common neurological signs were altered consciousness (n = 42, 26.2%), circling (n = 36, 22.5%), and seizures (n = 36, 22.5%). Cats without specific neurological signs were common (n = 34, 21.2%). The tumor was considered an incidental finding in 30 (18.8%) cats. In addition to expected relationships (eg, meninges and meningioma, pituitary and pituitary tumors), we found that lesion location was predictive of tumor type with diffuse cerebral or brainstem involvement predictive of lymphoma and third ventricle involvement predictive of meningioma.  相似文献   

20.
Comparison of different tests to diagnose feline infectious peritonitis   总被引：1，自引：0，他引：1  
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