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1.
将PCR扩增的鸡大肠杆菌1型菌毛蛋白结构基因(pilA)用地高辛标记成核酸探针与分属28个血清型的50个鸡大肠杆菌分离株进行斑点杂交,阳性率达84%,用甘露糖敏血凝试验(MSHA)检测阳性率为72%,表明核酸杂交比MSHA法更敏感。  相似文献   

2.
导致鸡发生败血症的大肠杆菌一般具有F1(I型)菌毛(由Pil同源基因群编码)和/或P菌毛(由pap同源基因群编码),这些菌毛通常被认为与感染和定殖有关。本实验以3株致病大肠杆菌(E.coli)O1(Pil^+/pap^+)、O2(pil^+/pap)和O78(pil^+/pap^+)通过气管内注射1.5周龄鸡,旨在探讨由不同毒力因子引起传染的动力学变化及其菌毛在体内的表述,感染后3~144小时剖检  相似文献   

3.
用地高辛标记鸡大肠杆菌P型菌毛结构基因(papA)制成核酸探针,作斑点杂交试验,检测28个血清型鸡大肠杆菌50个菌株与该探针的同源性。结果表明有5个菌株被检测为阳性,阳性率为10%。  相似文献   

4.
鸡大肠埃希氏菌菌毛分类方法的研究   总被引:1,自引:0,他引:1  
用D-甘露糖敏感血凝特性(MSHA/MRHA)及聚合酶链反应(PCR)扩增2种方法对鸡大肠埃希氏茵茵毛进行分类,证明MSHA/MRHA具有方便,快速及较可靠的特点,但不太敏感;PCR则具有快速速、敏感、准确、可靠的优点,用PCR对鸡大肠埃希氏茵进行分类是一种十分有效的新方法。  相似文献   

5.
从禽病原性大肠杆菌分离株TK3(O1)提取I型菌毛免疫BAIB/c小鼠,取其脾细胞与小鼠骨髓瘤细胞融合,获得4株能稳定分泌针对I型菌毛的单克隆抗体杂交瘤细胞株,分别命名为aB6、bG5、cF3和cG3。单克隆阻断甘露糖敏血凝试验,免疫胶体金和Western blot试验证明,单抗是I型菌毛特异的。这些单抗培养上清及腹水的ELISA效价为分别为10^-2~10^-3和10^-5~10^-6;腹水的平  相似文献   

6.
应用RT-PCR技术,从分泌具有中和活性的抗A型产气荚膜梭菌α毒素单克隆抗体(McAb)的杂交瘤细胞1A8中,扩增出抗体VH和VL基因,用linker(G1y4Sir3) 3基因,将VH和VL基因连接成SeFV基因,并将其克隆至pGEM-T载体中。经核甘酸序列分析证实,VH和VL基因及linker基因拼接正确,基因全长729bp,经计算机分析,VH和VL基因均为新发现的基因序列,符合功能性重排的鼠抗体可变区基因特征。  相似文献   

7.
用提取的 A 型产气荚膜梭菌 α毒素包涵体免疫 B A L B/c 小鼠后, 取小鼠脾细胞与 S P2/0 骨髓瘤细胞进行融合和克隆化,经间接 E L I S A 筛选,共获得 1 A8、1 C3、1 D5、1 D8、1 F1、1 H1 和 2 E3 7 株稳定分泌单克隆抗体( M c Ab)的杂交瘤细胞株。经鉴定,7 株 M c Ab 的 Ig 亚类有 Ig G1(1 D8)、 Ig G3(1 A8、1 C3 和 2 E3)和 Ig M(1 D5、1 F1 和 1 H1)。细胞培养上清和腹水抗体效价分别为 1∶512~1∶1 024 和 1∶106 ~1∶108 。尤为重要的是,2 E3 杂交瘤细胞株分泌的 M c Ab 不仅能够中和 α毒素的磷脂酶 C活性和溶血活性,而且能够对致死性腹腔感染小鼠产生良好的被动保护作用。  相似文献   

8.
以人工合成的针对血清I号马立克氏病病毒(MDV1)A抗原基因(gA)部分序列的两端寡聚核苷酸为聚合酶链反应(PCR)的引物,分别对马立克氏病病毒血清I型(京-1株,MD11/75C株);2型(SB-1株);3型(火鸡疱疹病毒的FC126株)毒株和GA株BamHI B片段的PACY184克隆重组质粒DNA进行基因扩增反应及其敏感性试验。结果表明,该引物不仅对MDV1具有较强的特异性,而且由此引物引导  相似文献   

9.
鸡大肠埃希氏菌菌毛表达、血凝谱及粘附特性研究   总被引:4,自引:0,他引:4  
对6株具有不同致病性的鸡大肠埃希氏菌分离株体外菌毛的表达、对13种不同红细胞血凝谱及血凝方式、对鸡胚成纤维细胞(CEF)及在体内外对1日龄鸡气管组织的粘附特性进行了研究,结果表明,具有致病性的菌株,在体外适宜的条件下,能表达菌毛,非致病性菌株不表达。不同菌株的血凝谱及血凝方式具有差异,除中等致病性菌株MG30e对大鼠红 细胞(RBCF)的凝集不能被D-甘露糖抑制,表现为抗甘露糖型血凝(MRHA)外,  相似文献   

10.
HIV—2gag基因在重组痘苗病毒中的表达   总被引:1,自引:1,他引:0  
以痘苗病毒HA基因为侧翼,将HIV-2gag基因部分序列(简称G1)和全部序列(简称G2)分别插入牛痘病毒A型包涵体(ATI)和串联10个(与HA基因反向)或16个(与HA基因同向)痘苗病毒P7.5组成的复合型启动子下游,构建了4个重组痘苗病毒表达载体质粒。经脂质体转染、鸡红细胞吸附试验筛选和免疫荧光鉴定,获得4株能稳定表达目的蛋白的重组痘苗病毒。实验结果表明,以HA基因为侧翼构建重组病毒的重组率约为0.1%,阳性重组率为25%~100%。实验中还发现,以HA基因为侧翼的重组痘苗病毒能够引起细胞融合,其可作为筛选重组痘苗病毒的另一种标志。Westernblot结果表明,表达的Gag蛋白能被HIV-2血清中的特异性抗体所识别,并能诱导小鼠产生抗HIV-2Gag抗体。  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.
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