首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 315 毫秒
1.
副猪嗜血杆菌国内流行血清型菌株的生物学特性比较研究   总被引:1,自引:0,他引:1  
本研究对我国最流行的HPS血清4、5、12、13和14型共16株细菌的菌体形态、生长速度、生化特性、小鼠毒力等生物学特性进行了比较研究。革兰染色镜检结果表明,除4型菌株H4L3外,同一血清型HPS的菌体形态比较一致;不同血清型HPS的菌体形态具有明显差异,且具有型特异性。培养结果表明,在TSA固体培养基上生长24h后的菌落平均直径大小依次为13型2.02mm、4型1.91mm、5型1.80mm、14型1.71mm、12型1.66mm,同一血清型的不同菌株之间无显著差别。生化试验结果表明不同血清型HPS的生化反应存在明显差异,即使是同一血清型的不同菌株之间也有较大差别。小鼠毒力试验结果表明,除4型外,毒力强弱依次为血清12型、14型、5型、13型,其LD50分别介于(2.74.6)×108、(4.34.6)×108、(4.37.9)×108、(1.07.9)×108、(1.01.3)×109、(2.31.3)×109、(2.32.8)×109 CFU之间,同一血清型的不同菌株之间无显著差别。在血清4型菌株中,H4L3的毒力明显偏强(LD50为3.6×108 CFU),其他菌株的LD50介于(1.42.8)×109 CFU之间,同一血清型的不同菌株之间无显著差别。在血清4型菌株中,H4L3的毒力明显偏强(LD50为3.6×108 CFU),其他菌株的LD50介于(1.41.6)×109 CFU之间。本研究为HPS不同血清型的快速鉴定、致病机理和疫苗研发等提供了理论依据。  相似文献   

2.
为弄清某规模化养猪场感染和流行的副猪嗜血杆菌(HPS)菌株的耐药性、血清型及基因型,本试验自该猪场发生浆膜炎和关节炎病猪的不同组织样品中分离到6株HPS菌株,通过细菌培养特性、生化试验和PCR扩增细菌16S rRNA基因片段并测序对分离株进行鉴定;进而鉴定分离株对不同类别抗生素的耐药性;最后对分离株进行血清分型和RAPD基因分型并分析两者的相关性。结果显示,自病猪不同组织脏器中分离鉴定了6株HPS菌株,体外培养具有典型"卫星生长"现象;生化试验结果符合HPS反应特性;PCR均可扩增出821 bp的HPS 16S rRNA基因片段,且序列与HPS一致。药敏试验结果显示分离株对头孢菌素类、青霉素类、氨基糖苷类、大环内酯类和四环素类抗生素敏感,而对喹诺酮类、磺胺类、林可霉素类和氯霉素类抗生素产生耐药性。琼脂扩散试验结果显示HPS分离株均为血清5型;RAPD分析显示HPS分离株与15个血清型参考菌株可分为4个基因型。本试验结果为HPS的流行病学调查及防控具有一定的借鉴价值。  相似文献   

3.
为调查研究河南规模化猪场副猪嗜血杆菌(HPS)流行优势菌株及其耐药性情况,2017-2018年从河南规模化猪场分离到30株HPS,根据菌株分离部位统计,肺脏、气管是HPS分离的首要组织部位,肺脏分离14株,占46.67%;气管分离11株,占36.67%。通过PCR分子血清型鉴定,河南流行的优势菌株为血清5,7,4型,其中血清型5型有9株,占30%;血清型7型有5株,占16.67%;血清型4型有4株,占13.33%。通过K-B纸片琼脂法药敏试验,30株分离菌株除对头孢噻呋100%敏感外,对其他17种常用抗生素都有不同程度的耐药现象,多重耐药现象突出,预防控制HPS病选药、用药方面更需慎重和规范。  相似文献   

4.
为在临床诊断中快速鉴定副猪嗜血杆菌(HPS)血清4型和13型等优势流行血清型,分子血清分型方法较常规的基于特异性抗血清的血清分型方法更加准确和高效。根据HPS血清4型脂多糖合成蛋白基因wcip4和血清13型糖脂转移蛋白基因gltP序列设计特异性引物,分别建立了简便快速鉴定HPS血清4型和13型的环介导等温扩增方法(LAMP)。特异性检测结果显示,HPS血清4型或13型参考菌株检测为阳性,而其他HPS血清型参考菌株及19种其他细菌检测均为阴性;敏感性检测结果显示,在25μL反应体系中,HPS血清4型和13型基因组DNA检测限分别为1 pg和2.5 pg。对已知血清型的22株HPS临床分离株检测结果显示,13株血清4型和5株血清13型分别检测均为阳性,而其他血清型分离株检测均为阴性。结果表明,建立的LAMP方法可用于HPS血清4型和13型的快速鉴定,有助于HPS优势流行血清型的快速调查及疫苗防控。  相似文献   

5.
为了了解闽西地区副猪嗜血杆菌(HPS)流行的主要血清型及毒力情况,试验对来自闽西地区的患病猪进行了副猪嗜血杆菌的分离鉴定及血清分型,并选取7株血清5型临床分离株进行小鼠毒力试验。结果表明:41株临床分离株中15株为血清5型,6株为血清4型,其余为1型4株、2型2株、12型1株、13型1株、未定型7株,5株存在血清型交叉。7株5型代表株在LD50(2×109cfu)时小鼠死亡率差异明显,其中LY02株小鼠致死率最高(80%),并可引起小鼠以支气管肺炎、肝炎、肾小球肾炎、心肌炎、脾炎为主的组织病理学变化。说明闽西地区HPS流行的主要血清型为5型(36.6%)和4型(14.6%),其中LY02血清5型代表株可能为高致病潜力株。  相似文献   

6.
宁夏部分地区鸡大肠埃希菌的分离与血清型鉴定   总被引:1,自引:0,他引:1  
为调查宁夏地区鸡大肠杆菌病的流行情况,采集宁夏4个地区的103个规模化鸡场疑似病料151份,通过病原菌分离鉴定及生化试验,鉴定出鸡大肠埃希菌109株,平均分离率为72.19%(109/151);动物试验证实,59株分离菌有致病性,占分离菌54.13%(59/109);对致病性菌株进行血清型鉴定,确定血清型种类13种38株,占致病性菌株64.41%(38/59);优势血清型分别为O15、O18、O78、O88,占定型菌株63.16%(24/38)。  相似文献   

7.
为筛选副猪嗜血杆菌最适培养基,将副猪嗜血杆菌血清5型标准株(Nagasaki菌株)接种固体培养基TSA、PPLO琼脂、巧克力琼脂、胰月示蛋白胨琼脂和液体培养基TSB、PPLO液体、胰月示蛋白胨和马丁肉汤,通过观察菌落大小和平板计数,筛选出副猪嗜血杆菌生长最适培养基。将Nagasaki菌株接种TSB培养基,取10h~16h不同培养阶段的培养物,腹腔接种豚鼠,确定副猪嗜血杆菌感染实验动物的最佳培养阶段。结果表明,TSA和TSB是副猪嗜血杆菌的最适培养基,副猪嗜血杆菌血清5型接种于TSB中,在37℃、200r/min培养10h~13h,菌数可达到10^9cfu/mL。  相似文献   

8.
从陕西省关中地区患多发性浆膜炎和关节炎猪场的32个样品中分离到6株细菌,并对其进行了形态观察、菌落纯培养、生化特性鉴定、PCR检测等,最终确定分离菌株均为副猪嗜血杆菌.该结果表明,关中地区存在副猪嗜血杆菌病流行;对副猪嗜血杆菌分离株最适培养基进行了筛选,将分离菌株分别接种于LB、TSA、巧克力琼脂等固体培养基上,接种12 h后通过观察菌落大小,筛选出最适合副猪嗜血杆菌生长的固体培养基TSA(加0.1 g/L NAD和50 mL/L的犊牛血清)和固体培养基巧克力琼脂(加0.8 g/L NAD).同时,将副猪嗜血杆菌分离菌株接种于LB、TSB等液体培养基中,培养至16h后,每隔4h分别取样,通过与麦氏比浊管对比确定菌液中的菌数,筛选出最佳液体培养基为TSB(加0.1 g/L NAD和50 mL/L的犊牛血清).  相似文献   

9.
为了解和掌握近年来副猪嗜血杆菌病在猪群中的流行情况,本研究2013年~2017年从河南及其周边省份的2445个病例样品中分离出531株副猪嗜血杆菌(HPS),总分离率为21.70%。通过PCR分型方法和KRG琼脂扩散分型方法对其中217个分离菌株进行了血清型鉴定。结果显示,河南及其周边省份流行最广的HPS血清型为4型(62株,28.57%),其次是5型(38株,17.51%)、12型(26株,11.98%)、13型(18株,8.29%)、7型(16株,7.37%)和14型(12株,5.53%),以及少量1型、2型、3型、8型、10型、11型和15型,未鉴定出6型和9型,未能定型的有24株(11.06%)。不同组织的分离结果显示,肺脏HPS的分离率最高,为21.51%(526/2445);其次是心血占18.75%(439/2341)和脑18.21%(57/313),淋巴结、关节液及肝脾中HPS的分离率均在10%以下。2013年~2017年,不同年份的HPS分离率介于18.12%~30.31%,不同月份的分离率介于15.64%~29.66%,其中夏季的分离率最低,冬季最高。HPS最常见的共感染菌是链球菌,占所有共感染病料样品的40.76%(128/314),其次是大肠埃希菌占30.89%(97/314)和多杀性巴氏杆菌占13.69%(43/314)。以上结果表明,近年来HPS在河南及周边省份猪群中仍广泛流行和致病;4型仍是最流行的血清型,但5型流行明显下降,7型和12型分离率明显上升;结果还表明该病的发生具有明显的季节性,且与其它病原菌的共感染情况非常严重。本研究对近年来HPS流行情况与规律、血清型分布及其协同感染情况进行了系统调查和分析,为客观评估副猪嗜血杆菌病的危害及其综合防控提供了参考依据。  相似文献   

10.
旨在明确副猪嗜血杆菌(HPS)临床分离株分离部位的组织分布,进而探讨其血清型和基因型的流行分布特点及相关性,为猪格氏病(Glässer's disease)的有效防控提供科学依据。针对临床分离鉴定的89株HPS,利用PCR技术鉴定血清型,统计各血清型HPS在不同分离部位的菌株分布数量;应用多位点序列分型(MLST)方法进行序列类型(ST)鉴定分析、位点多态性分析、BURST分群统计和UPGMA系统发育树聚类分析。89株HPS临床分离株共鉴定出9种血清型(1、2、4、5、7、11、12、13、14)以及未定型(NT),血清4、13、7和5型为优势血清型,分别占比28.09%、22.47%、13.48%和10.11%,有64株HPS分离于肺,占比71.91%;24种ST型,ST267、ST268、ST387和ST365为优势基因型,分别占比26.97%、21.35%、8.99%和5.62%,每个基因位点存在3~13个等位基因,多态性位点从3(g3pd)到71(6pgd)不等,BURST分析中划分为2个单个ST型和11个克隆群(CC),UPGMA系统发育树被分为4个分支,优势ST型处于2、3、4三个分支中,均对应具有毒力血清型的HPS分离株。HPS临床分离株流行血清型和基因型呈现多元化,具有明显的遗传异质性,同时,ST型与血清型存在一定的交叉性,且与HPS临床致病力相关。  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.
14.
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   

15.
Our particular attention in this article was given to natural mediators for macrophages isolated from the sites of tissue injury. A number of chemotactic factors, which may satisfy many criteria making them acceptable as inflammatory leucocyte chemotactic factors, has been separated. Among them, our laboratory has isolated three macrophage (monocyte) chemotactic factors (MCF-a, -b and -c). Their purification, characterization and functional specificity are discussed.  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.
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   

18.
The objective of this report was to characterize 20-year changes in proportion of calcium oxalate (CaOx) calculi and struvite calculi in dogs, and associations with breed, age, and sex. In this retrospective study, results of analysis of urinary calculi from dogs were reviewed for specimens received between July 1, 1981, and December 31, 2001. Breed, sex, age, year of submission of the specimen, and mineral type(s) were analyzed statistically. CaOx or Struvite or both were contained in 18,966 of 20,884 (91%) specimens. For both sexes, a 20-year statistically significant increase was observed in the proportion of calculus specimens that contained CaOx. The increase in this proportion was greater in females (1% to 31%) than in males (18% to 82%). From 1998 to 2001, when proportions may have plateaued, the odds of specimens containing CaOx were markedly higher in 18 breeds, markedly lower in 5 breeds, and not significantly different in 13 breeds compared with crossbreds. For both sexes, a 20-year statistically significant decrease was observed in the proportion of calculus specimens that contained struvite. This decrease in proportion was greater for males (79-16%) than for females (97-68%). From 1998 to 2001, when proportions plateaued, the odds of calculi containing struvite were markedly lower in 20 breeds, markedly higher in 1 breed, and not significantly different in 15 breeds when compared with crossbreds. Breed, age, and sex were associated statistically with CaOx or struvite urolithiasis. In conclusion, there appears to have been a long-term increase in the proportion of specimens of canine urinary calculi that contain CaOx as well as a long-term decrease in the proportion of specimens of calculi that contain struvite for both male and female dogs. The rate of change appeared to begin leveling off in the period 1998 to 2001. The recent proportion of dogs with either CaOx- or struvite-associated urolithiasis may depend on breed, age, and sex, and on interactions among these 3 factors.  相似文献   

19.
<正>1.INTRODUCTION Ensuring transportation network security is one Of the most daunting challenges confronting homeland security agencies today.Significant research has been dedicated.To model and analyze the vulnerability of transportation systems,while notably fewer studies propose specific strategies for deploying defensive technologies to safeguard these systems.  相似文献   

20.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号