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1.
鸭疫里氏杆菌免疫原性研究   总被引:6,自引:1,他引:5  
本研究应用电镜对Ⅰ型鸭疫里氏杆菌荚膜进行了初步观察,在电镜下,负染的菌体周围呈一电子透明层;未经抗体处理的细菌超薄切片,荚膜在菌体周围呈松散的絮状结构,而应用同源抗体处理后,荚膜呈一均匀层。同时在超薄切片中还看到细菌的空泡和外膜结构。采用十六烷基三甲基溴化铵(CTAB)成功地提取了培养物上清液中的荚膜成分,经过测定比较,加入5mM CTAB时效果最佳。  相似文献   

2.
黄连汤对鸭疫里默氏菌的抑菌作用及对菌体形态的影响   总被引:2,自引:1,他引:1  
研究中药复方黄连汤水提醇沉浓缩物(Ethanol extracts ofCoptidis rhizomadecoction,EeCrd)对鸭疫里默氏菌(Riemerella anatipestifer,RA)的体外抑菌规律及其对菌体形态的影响。黄连汤经水提醇沉后,减压浓缩,制成含生药176g.L-1的EeCrd原液。用PBS将原液倍比稀释成88、88×2-1、88×2-2……88×2-9g.L-1等11个梯度浓度的药液。用纸片扩散法和液体倍比稀释法研究EeCrd完全抑菌时的最小抑菌浓度和不完全抑菌时的亚抑菌浓度;取88和88×2-3g.L-1EeCrd浓度组药液分别作用17和3、6、17h后的细菌,用透射电镜观察菌体形态的变化。纸片扩散法和液体倍比稀释法测定的EeCrd完全抑制RA时的最小浓度均为88×2-2g.L-1,不完全抑菌时亚抑菌浓度为88×2-3g.L-1;88×2-4g.L-1以上稀释度EeCrd基本无抑菌活性;50μL的88g.L-1浓度组的EeCrd作用RA17h后,RA菌体浓缩,变小,最终死亡;50μL的88×2-3g.L-1浓度组的EeCrd作用RA3、6、17h后,RA菌体长度变长,细胞壁变薄,菌内颜色变浅,皱褶减少,纹理不均匀,菌体干瘪、折叠、弯曲,最终死亡。EeCrd可能通过破坏RA外膜结构来抑制细菌增殖。  相似文献   

3.
本研究应用电镜对Ⅰ型鸭疫里氏杆菌的荚膜进行了初步观察,在电镜下,负染的菌体周围呈一电子透明层;未经抗体处理的细菌超薄切片,荚膜在菌体周围呈松散的絮状结构,而应用同源抗体处理后,荚膜则呈一均匀层。同时在超薄切片中还看到细菌的空泡和外膜结构。采用十六烷基三甲基溴化铵(CTAB)成功地提取了培养物上清液中的荚膜成分,经过测定比较,加入5mMCTAB时效果最佳。  相似文献   

4.
本研究建立了检测鸭疫里默氏杆菌(Rimerrlla anatipestifer,RA)抗体的全菌体抗原间接ELISA方法,最佳血清稀释倍数为1:100。以RA1的甲醛灭活全菌体为包被抗原,棋盘滴定法试验确定其最适抗原包被浓度为5×10^8CFU/mL。与全菌体裂解抗原和重组P25蛋白为包被抗原的间接ELISA方法相比较,三者均可检测不同血清型RA标准阳性血清,结果符合性良好。用该方法检测雏鸭接种鸭疫里默氏杆菌蜂胶灭活疫苗后血清抗体水平的变化,发现免疫后10天抗体水平开始上升,二免后10天抗体水平达到峰值。  相似文献   

5.
间接免疫组化法检测鸭疫里默氏杆菌感染和抗原定位   总被引:8,自引:1,他引:8  
应用鸭源血清1型鸭疫里默氏杆菌(RA)作为抗原。免疫兔制备兔抗RA的IgG。建立了检测雏鸭感染鸭疫里默氏杆菌的间接免疫酶组织化学法。该法检测大肠杆菌(O1、O8、O79、O138)、鸭沙门氏菌、多杀性巴氏杆菌(5:A)感染发病死亡雏鸭组织。不出现阳性反应,而检测RA感染发病死亡雏鸭组织出现特异性阳性反应;检测RA人工发病死亡雏鸭。可在心脏、肝脏、肺脏、肾脏、十二指肠、盲肠、直肠、脾脏、法氏囊、胸腺、胰脏、脑和腺胃检测到RA抗原,RA抗原分布于细胞浆、组织间隙和血液;检测RA人工感染病例与RA肝脏分离符合率为100%,检测临床可疑病例的血清1型RA的阳性率(92.96%)比细菌分离率(75.12%)高。该法具有特异、直观和敏感的特点,可用于雏鸭RA人工感染和临床感染的诊断、检测及RA抗原定位和RA致病机理的研究。  相似文献   

6.
抗鸭疫里氏杆菌OMP单克隆抗体间接ELISA筛选方法的建立   总被引:1,自引:0,他引:1  
鸭传染性浆膜炎病原为鸭疫里氏杆菌(riemerella anatipestifer,RA).目前世界上报道的RA血清型共有21型,且血清型有变化和增多的趋势,RA各血清型间无交叉免疫保护作用[1-3].许多研究表明:RA的抗原类型为荚膜抗原和菌体抗原,血清型不同,荚膜及菌体表面免疫原蛋白也不相同.苏敬良等通过超速离心法提取了RA其外膜蛋白并研究了其免疫原性,认为44 kD的外膜蛋白是其主  相似文献   

7.
3型鸭疫里氏杆菌的分离与鉴定   总被引:3,自引:0,他引:3  
采集福州市北郊某番鸭场接种过1型和2型鸭疫里氏杆菌(RA)双价灭活疫苗而发病死亡的雏鸭肝,从中分离到1株RA,经对分离菌培养特性、形态观察和血清型鉴定,属3型RA。  相似文献   

8.
通过超薄切片和透射电子显微镜技术对鸭病毒性肠炎病毒(DEV)CH强毒株在鸭胚成纤维细胞(DEF)中的形态结构进行了研究。结果发现,DEVCH强毒株病毒核酸呈圆形颗粒状,直径35~45nm,在胞核内常集中分布;病毒核衣壳呈圆形.直径90~100nm.在胞核和胞浆内都有分布;DEV核衣壳可根据所含核酸形态的差异分为空心核衣壳、内壁附有颗粒型核衣壳、同心圆形核衣壳和实心核衣壳;成熟的病毒粒子具有囊膜和皮层结构.呈圆形.直径150~300nm,存在于胞浆空泡内;DEV可在DEF中分别形成胞浆内和胞核内包涵体结构;伴随子代病毒在细胞内的出现,胞浆内迁出现豆英状、马蹄形、半圆形、圆形、同心圆形等与病毒发生有关的电子致密结构。  相似文献   

9.
鸭疫里氏杆菌不同血清型广西株的分离鉴定   总被引:9,自引:0,他引:9  
从广西部分地区9个发病鸭场的病料中分离出9株疑似鸭疫里氏杆菌,经培养特性、形态、染色性及生化反应特性等鉴定为鸭疫里氏杆菌(RA)。RA血清型分型试验结果表明,9株分离菌中有7株(GX1、GX2、GX3、GX4、GX5、GX6、GX8)属血清型Ⅰ型;另2株(GX7、GX9)与GX1株的阳性血清无交叉凝集反应,GX7、GX9株制备的阳性血清也无交叉凝集反应,表明这2株菌既非Ⅰ型又不属同型的RA。经致病性试验,GX1株具很强的致病力,能使北京鸭和本地麻鸭发病死亡,GX7和GX9株仅能使北京鸭发病死亡,而不致本地麻鸭发病。结果表明,广西存在着不同血清型的RA,而且有的菌株致病性很强。  相似文献   

10.
为研究鸭疫里默氏菌(RA)对SPF鸭的致病性,本实验室从不同省份疑似RA感染鸭场分离到4株细菌,经菌落形态观察、染色镜检、生化鉴定确定为RA。药敏试验表明这4个分离株对嗯诺沙星、氧氟沙星和先锋霉素V相对敏感,但对卡那霉素和庆大霉素均耐药。外膜蛋白A(OmpA)基因的克隆测序结果显示,4个RA分离株的ompA基因全长均为1 164 bp,编码387个氨基酸;核苷酸同源性为89%~100%。将5×108cfu的HLG1分离株经颈部皮下接种SPF鸭,病死SPF鸭的心、肝、脾、肺、脑和肾具有典型的病变。RA的分离鉴定技术为SPF鸭群RA的检测和监测以及为培育和净化SPF鸭作为RA的致病机理和疫苗研究中的实验动物模型奠定了基础。  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.
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   

16.
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   

17.
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   

18.
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   

19.
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   

20.
Infectious diseases have always been a terrible scourge for humans. The appearance of these plagues, as they were called without distinction, was generally connected to various conditions: asters, climatic changes or religious reasons. The concept of contagious, and then infectious, diseases came slowly. Variolation, i.e. transmission of ‘virulent’ matter to induce a natural disease and the immunity against it, was brought from Constantinople to England by Lady Montague, in 1721. This ‘variolation’ technique was also often performed in veterinary medicine against diseases like sheep-pox or pleuropneumonia. As ‘vaccination’ is the term generally accepted for ‘immunisation’, variolation can be the word designating such a technique. The second period of the history of immunisation began, in 1880, with the studies of Pasteur and his collaborators. A great number of bacterial vaccines were developed: dead, live but attenuated or only parts of pathogens. The viruses were produced in animals, then in eggs and at last, in tissue cultures. Second generation vaccines appeared with genetic engineering: recombinant vaccines, vector vaccines, nucleic acids vaccines, and markers vaccines, among others. These novel technologies can permit the development of new ones and improve the quality of the vaccines already existing.  相似文献   

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