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1.
根据Gen Bank上已发表的H3N2亚型的猪流感病毒NS基因序列,设计合成一对引物,对四个猪流感病毒广东株提取RNA,运用RT-PCR方法获得了4株H 3N2亚型猪源流感病毒广东分离株A/Swine/Guangdong/01/04(H 3N2)、A/Swine/Guangdong/02/04(H 3N2)、A/Swine/Guangdong/03/04(H 3N 2)、A/Swine/Guangdong/04/04(H3N2)的NS基因序列,并对所得序列进行比较分析.序列分析表明,四个毒株NS基因的核苷酸序列与参考毒株的NS基因相似性高迭90%以上,说明近年来广东的H 3N2亚型猪流感病毒NS基因变异较小.遗传进化关系表明本实验四个毒株的NS基因和香港2000-2002年间的猪流感病毒的NS基因与1998-2002年间美洲流行的人流感病毒的NS基因在遗传进化树中位于同一个分支,这说明它们可能有着相近的亲缘关系.  相似文献   

2.
从湖南分离得到一株H5N1亚型禽流感病毒(AIV),首先设计合成两对HA和NA基因特异性引物,采用两步法RT-PCR,对鸭流感病毒株 A/Duck/HunanWugang/2/2004(H5N1)(简称DK/HNWG/2/04)的表面蛋白基因进行序列测定,并与国内外已经发表的H5N1亚型毒株表面蛋白基因进行序列分析和比较.结果表明,HA和NA基因全长分别约为1.7 kb和1.4 kb,分离株与14个参考毒株HA基因的同源性为95.9%～98.0%,NA基因的同源性为87.0%～98.4%.根据HA基因核苷酸序列推导HA裂解位点氨基酸,发现分离株的裂解位点包含多个碱性氨基酸,符合高致病性禽流感的特征.  相似文献   

3.
2008年从湖北省分离到1株H3N8亚型马流感病毒A/equine/Hubei/6/08。以2002年美国KENTUKY株为模板设计HA基因测序引物,进行RT-PCR,然后测定该分离株的HA基因核苷酸序列。经NCBI上Blast同源性比较发现,与A/equine/Newmarket/5/2003(H3N8)同源性较高为98.7%。HA蛋白遗传进化分析表明该毒株隶属于H3N8亚型马流感病毒中的美洲系福罗里达亚系。该株与OIE现在推荐的疫苗候选株A/equine/Kentuck-y/5/2002(H3N8)HA1蛋白氨基酸序列比对发现有3处氨基酸替换位点;与OIE以往推荐的疫苗候选株A/e-quine/Kentucky/1/1994(H3N8)比对发现有11处氨基酸替换位点。研究结果表明该分离株可作为中国研制马流感疫苗的候选株。  相似文献   

4.
为了解广东猪流感病毒(SIV)的流行变异情况,2010年11月从广东某规模猪场采集流感症状的猪鼻拭子60份,接种10日龄SPF鸡胚,分离到1株猪流感病毒,通过流感分型RT-PCR和HI试验鉴定为H3N2亚型SIV,命名为A/swine/Guangdong/L22/2010(H3N2),进行全基因序列测定及相似性分析发现,该分离株有低致病性流感分子特征,该毒株的8个基因片段连同最近广东猪群流行的流感毒株与2000年前后H3N2人流感病毒有较高的同源性.系统遗传演化显示,该病毒分离株可能是由1999年人源H3N2流感病毒A/Moscow/10/99(H3N2)进化而来.  相似文献   

5.
对3株H1N2亚型猪流感病毒(SIV):Sw/GX/17/05、Sw/HN/1/05和Sw/GX/13/06的血凝素(HA)、核蛋白(NP)、神经氨酸酶(NA)、基质蛋白(M)和非结构蛋白(NS)基因进行克隆和序列分析.结果显示:3株分离毒株HA、NP、NA、M和NS基因之间核苷酸同源性分别为91.3%～98.0%、98.4%～98.8%、97.4%～98.3%、98.8%～99.8%和98.1%～98.4%.遗传进化分析显示:分离毒株与美国分离的三源基因重排H1N2 SIV具有较近的亲缘关系;在HA、NP、M和NS基因进化树中,3株分离毒株均位于古典H1N1亚型SIV群,在NA基因进化树中,3株分离毒株则位于人流感病毒群.HA和NA基因推导氮基酸序列分别与代表毒株古典H1N1 SIV A/swine/Maryland/23239/1991(H1N1)和人H3N2流感病毒A/Buenos Aires/4459/96(H3N2)比较分析显示:HA(95.4%～96.1%)和NA(96.6%～97.2%)具有较高的氨基酸同源性;糖基化位点、抗原位点和受体结合位点(HA)处氨基酸存在一定的差异,这些氨基酸差异对病毒生物学特性的影响有待于进一步研究.  相似文献   

6.
用RT-PCR方法扩增了H9N2亚型猪流感病毒河南株(Swine/Henar/Y1/09)和H9N2亚型猪流感病毒上海株(Swine/Shanghai/Y1/09)的8个基因片段,进行测序分析.结果表明,这两株猪流感病毒HA基因长度均为1701 bp,编码566个氨基酸,HA切割位点序列均为R-S-S-R-G,属非高致病性毒株;这两个毒株的HA蛋白均有8个潜在的糖基化住点.两个分离株的NA基因长度为1401 bp,编码467个氨基酸,这两个毒株均在茎区63、64、65位发生氨基酸缺失.两株猪流感病毒HA基因的同源性为96.6％,NA基因的同源性为98.6％.两株毒株的8个基因片段系统发生树分析表明它们均为重组体,与2008年上海地区健康鸡群中分离的H9N2亚型毒株(Ck/Shanghai/Y 1/2008)8个基因片段均分别属于同一个基因群.  相似文献   

7.
本研究从广东省某猪场采集37份疑似猪流感症状的猪鼻拭子样品,接种于9日龄SPF鸡胚并收集尿囊液,通过血凝试验、血凝抑制试验和RT-PCR鉴定,分离得到一株猪流感病毒,经RT-PCR分别扩增8个基因片段,进行基因测序及序列分析,与GenBank收录的参考毒株比对并构建进化树。结果显示,分离毒株为H1N1亚型猪流感病毒,将其命名为A/swine/Guangdong/2/2018(H1N1)。遗传进化分析显示,分离株8个片段的核酸序列与A/swine/Guangdong/L3/2009(H1N1)对应序列的同源性均达99%以上,与经典型H1N1亚型猪流感病毒处于同一分支。分离毒株HA的裂解位点为PSIQSR↓GL,符合低致病性流感病毒分子特征。HA基因受体位点为190D、225G和226Q,表明本毒株既可以结合SAα-2,6-Gal型人类流感病毒SA受体,也有结合SAα-2,3-Gal型禽类流感病毒SA受体的可能,在28、40、104、304、498、557位氨基酸处有6个潜在糖基化位点;NA蛋白在50、58、63、68、98、146、235位氨基酸处有6个潜在糖基化位点,NA蛋白氨基酸序列活性中心位点为119E、199D、223I、275H、293R、295N,氨基酸分析位点未出现突变,表明本分离株对神经氨酸酶抑制剂类药物的敏感性较高,但在M2蛋白中,31位氨基酸由敏感型的(S)突变为抗药的(N),提示可能对金刚烷胺类药物产生耐药性。开展猪流感病毒分离鉴定与遗传进化分析将为广东地区的猪流感流行和变异情况提供重要信息。  相似文献   

8.
3株H9N2亚型禽流感病毒HA基因变异分析   总被引：2，自引：0，他引：2  
对近10年来在同一地区分离到的3株H9N2亚型禽流感病毒血凝素(HA)基因进行扩增和序列分析,探讨H9N2亚型流感病毒变异情况.3个毒株的HA基因全长1 683bp,编码560个氨基酸;其裂解位点均为R-S-S-R,属于低致病力毒株;推导的HA基因氨基酸序列均含7个相同的潜在糖基化位点,受体结合位点为禽源性流感病毒特异性序列,左侧臂氨基酸均为NGQQG,右侧臂均为GTSKA.3个分离株与参考株核苷酸与氨基酸同源率均较高,仅有一些非关键位点突变.它们均属欧亚种系,与A/Duck/Hong Kong/Y280/97代表株亲源关系较近.研究结果从分子水平上证明H9N2亚型禽流感病毒近年来未发生较大变异.  相似文献   

9.
为对2012年广州规模化养猪场疑似流感病料中分离鉴定的2株猪流感病毒A/swine/Guangdong/1519/2012(H3N2)(简称GD1519)和A/swine/Guangdong/1520/2012(H3N2)(简称GD1520)进行遗传进化及分子特征分析,对两株病毒进行了全基因组的测序分析。通过对其8个基因片段的基因来源进行分析,构建系统进化树,遗传进化分析结果显示GD1519 HA、PB2、PA和NP基因片段均来源于近期人源H3N2亚型Moscow/99-like亚分支;其NA和PB1基因片段来源于早期人源H3N2亚型Victoria/75-like亚分支;其M和NS基因片段来源于近期人源H3N2亚型New York/99-like亚分支。GD1520病毒的HA基因片段来源于近期人源H3N2亚型Moscow/99-like亚分支;其NA和PB1基因来源于近期人源H3N2亚型New York/99-like亚分支;其PB2、PA、NP、M和NS基因片段均来源于早期人源H3N2亚型Victoria/75-like亚分支。分析结果暗示2株病毒可能均由不同时期的类人源H3N2亚型流感病毒间基因重排而产生的新型H3N2亚型猪流感病毒。本研究结果进一步证明猪可能是不同来源流感病毒的基因"混合器",开展猪流感病毒相关分子流行病学研究具有重要的公共卫生意义。  相似文献   

10.
为了解广西各地区宠物犬流感病毒(CIV)的流行情况,本研究从9个地级市宠物医院采集了326份犬鼻拭子样品,经RT-PCR检测为CIV阳性后对其进行MDCK细胞分离病毒,并对分离株进行全基因组测序和序列分析。结果表明获得2株CIVs分离株,均属于人源谱系,与Moscow/10/99(H3N2)人流感病毒株的同源性大于99%。8个基因节段的核苷酸序列遗传演化分析显示,这2株CIVs与人源H3N2亚型猪流感病毒(SIV)最为相近,同在Moscow/99分支。HA1蛋白氨基酸位点分析显示aa190~aa196位点处仍保留SIV的受体相关结合位点(DQISVYA),但却改变了流行于人类的部分受体结合位点(DQTSLYT)。本研究为有效预防人-犬流感病毒传播提供了实验依据。  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.
Tropical Animal Health and Production -  相似文献   

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   

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