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1.
从山东地区疑似新城疫病毒(NDV)感染鸽群中分离到两株新城疫病毒分别命名为pigeon/China/bz12和pigeon/China/bz11,经蚀斑纯化后测定其鸡胚平均死亡时间(MDT)分别为76.6 h、78.8 h,1日龄雏鸡脑内致病指数(ICPI)分别为1.98、1.95,符合NDV强毒特征.设计NDV F基因特异性引物,使用RT-PCR从纯化后鸡胚尿囊液中扩增获得了约1 662 bp基因条带,序列测定确认为NDV F基因,其氨基酸一级结构包含553位氨基酸残基,F0蛋白裂解位点含112-RQKRF-117氨基酸序列,具有NDV强毒株分子特性.依据yellow基因序列同源性对获得2株NDV分离株和42株NDV参考毒株基因型分型,结果显示,2株鸽源NDV分离株都属于基因Ⅶ型,其与基因Ⅶ型NDV不同分离株同源性达93.5%~99.8%,与鸡源强毒NDV分离株Chicken/China/SD8/2010同源性高达99.8%,表明这两株鸽源分离毒株可能来源于感染的鸡群.  相似文献   

2.
2011年从广东一疑似新城疫病毒感染的养禽场通过SPF鸡胚接种试验、HA及HI试验和动物回归试验,生物学毒力指标(MDT,ICPI)测定,分离到一株新城疫毒株,命名为GD-X1-2011,并对该毒株进行了F基因的序列测定分析.GD-X1-2011株的MDT为45 h<60 h,ICPI为1.88> 1.6,分离毒株具有血凝性且能被NDV La Sota标准阳性血清抑制,动物回归试验鸡出现典型的新城疫症状.毒株GD-X1-2011F基因的裂解位点序列为112R-R-Q-K-R-F117,属于强毒裂解序列,其F基因与基因Ⅶ型毒株SD-WF07-2011同源性为97.5%,与其他不同基因型毒株的同源性在83.6%~90.1%之间.进化树分析GD-X1-2011株属于基因Ⅶ型毒株.  相似文献   

3.
从产蛋下降鸭群分离到两株新城疫病毒(NDV)(命名为Duck/China/SD6/2008和Duck/China/SD7/2009),经蚀斑纯化后测定其鸡胚平均死亡时间为77.6h,F蛋白裂解位点氨基酸序列为112-RRQKRF-117,符合强毒NDV的特征。根据F基因(374bp)对2个NDV分离株和30个NDV参考株进行基因分型结果表明,2个分离株均属于基因Ⅶ型。F基因和HN基因核苷酸序列同源性比较显示,2个鸭分离株与基因Ⅶ型NDV分离株同源性为94.1%~99.7%和94.4%~97.1%,与同期分离的鸡源NDV强毒株Chicken/China/SD4/2008同源性最高,分别为99.3%~99.5%和99.5%~99.7%,表明这两个鸭NDV毒株可能来源于感染NDV的鸡群。  相似文献   

4.
近年来,我国相继有新城疫强毒株出现的报道,为分析这些强毒株与疫苗株之间的遗传进化关系,研究新城疫的流行病学特点,文章以华中农业大学病毒室分离的YM毒株基因组RNA为模板,利用RT-PCR扩增F基因的cD-NA,将其连接入pMD18-T载体,经筛选证明已获得鸡副黏病毒YM毒株F基因的阳性克隆子。核苷酸序列和氨基酸序列分析表明,YM毒株属于NDV基因Ⅶ型强毒株;F蛋白氨基酸序列与中国标准强毒株F48E9 F蛋白氨基酸序列同源性为86%,与弱毒疫苗Lasota/46株氨基酸序列同源性仅为83%,证明为变异株,且其重要的抗原位点343位氨基酸由Leu→Pro,免疫原性发生了较大变化。从基因进化树也可见,其与中国标准强毒株F48E9,弱毒疫苗Lasota/46株的进化关系较远,这从分子角度解释了为什么高免的鸡仍然暴发新城疫。  相似文献   

5.
试验从吉林省通化某地发病死亡鸭子病料中分离到1株具有血凝性的病毒,通过血凝试验、血凝抑制试验、血清中和试验及融合蛋白(F)基因的扩增测序,初步鉴定为新城疫病毒,命名为TH-1株。该病毒鸡胚平均死亡时间(MDT)、1日龄雏鸡脑内接种致病指数(ICPI)及6周龄鸡静脉接种致病指数(IVPI)分别为53.4 h、1.85和2.575,表明该新城疫病毒为强毒。F蛋白多肽裂解位点为112-RRQKRF-117,符合新城疫强毒株裂解位点氨基酸序列,进一步证明该毒株为新城疫强毒株。F基因核苷酸及氨基酸同源性比对发现,TH-1株与中国野鸭源新城疫病毒分离株mallard China HLJ株的同源性最高,核苷酸同源性达到了99.3%,同为新城疫基因Ⅶ型毒株,与目前新城疫流行的主要基因型Ⅶ型相一致,为鸭源新城疫的有效防制提供了理论基础。  相似文献   

6.
蛋鸡输卵管积液中新城疫强毒的分离鉴定与分子特征   总被引:1,自引:1,他引:0  
从病鸡输卵管积液中分离了一株新城疫病毒(命名为SHY06),经蚀斑纯化后测定其鸡胚平均死亡时间和1日龄雏鸡脑内致病指数分别为52 h和2.0,F蛋白裂解位点氨基酸序列为112-RRQKRF-117,符合强毒NDV的特征.根据F基因(1-374 bp)对SHY06和19个NDV参考毒株进行基因分型结果表明SHY06属于基因Ⅶ型.F基因氨基酸序列同源性比较显示SHY06与基因Ⅶ型NDV分离株同源性为97.5%~99.5%,与基因Ⅸ型NDV(F48E9等)同源性为91.7%~92.4%,与基因Ⅱ型(疫苗株LaSota等)同源性为89.2%. HN基因氨基酸序列同源性比较显示SHY06与近年来分离株同源性较高,为92.1%~99.7%,与疫苗株(LaSota)和标准强毒株(F48E9)同源性较低,分别为87.6%和89.9%.  相似文献   

7.
从山东济南某非典型新城疫发病鸡群中分离到一株新城疫病毒株(ShD-5—06),研究其生物学特性表明,该病毒具有新城疫强毒株的一些特征。从该分离株扩增出其F和HN基因,并与标准株进行同源性比较,为探讨NDV是否发生变异提供理论依据。本试验通过RT—PCR法特异性地扩增出F和HN基因全基因序列,并对其与已经发表的序列进行核苷酸序列测定和分析。结果表明,ShD-5—06株的F和HN基因开放性阅读框架(ORF)为1662bp和1716bp,分别编码489个和571个氨基酸。与国外发表的部分新城疫病毒强毒株和弱毒株之间相应序列进行比较,F基因核苷酸序列的同源性在84.1%~88.7%之间,氨基酸同源性在88.1%~93.3%之间;HN基因核苷酸序列的同源性在82.19,5~87.4%之间,氨基酸同源性在88.6%~90.9%之间;F蛋白裂解位点区(112~117)氨基酸组成与强毒株一致,说明NDV山东分离株(ShD-5—06)为新城疫强毒株。  相似文献   

8.
通过毒力测定、RT-PCR及F基因的序列测定与遗传进化分析,对2005-2008年从河北省部分地区的发病鸡群中分离到的10株新城疫病毒(NDV)进行了研究。各分离株经典毒力测定结果显示:MDT在37.6~54.4h之间,ICPI在1.71~2.0之间,IVPI值在2.16~2.8之间,均为新城疫病毒强毒株特征。F基因的序列测定表明,分离株之间的核苷酸序列具有77.4%~98.0%的同源性,与疫苗株Lasota的同源性为87.0%~98.9%,与国内标准强毒株F48E9同源性为89.7%~98.9%。推导其氨基酸序列分析表明,8个分离株的F蛋白的裂解位点氨基酸组成为112 R-R-Q-K-R-F117,具有NDV强毒株特征,与毒力测定结果相符,2个分离株的F蛋白的裂解位点氨基酸组成为112 G-R-Q-G-R-L117,与弱毒株特征相符。F基因分型和同源性比较显示:目前河北新城疫的流行以基因Ⅶ型为主(占70%),同时兼有基因Ⅱ型(占20%)和基因Ⅸ型(占10%)。  相似文献   

9.
从广东粤东地区某商品蛋鸡场的发病鸡群中分离到1株病毒(YS株),经血凝和血凝抑制试验确定为新城疫病毒(NDV).对该分离株的F蛋白氨基酸序列的分析结果表明,其F0裂解位点的氨基酸序列为1nR-R-Q-K-R-F117,且含有101K和121V,符合典型NDV强毒株的分子特点.遗传分析结果显示分离株属于基因Ⅶd亚型.F和HN基因的氨基酸相似性分析表明,分离株与基因Ⅶ型NDV Chicken/China/Shandong/02/2010株的相似性最高,均达到99%,而与常用疫苗株B1、V4、Clone30、Mukteswar和La Sota的相似性则较低,分别在86.8%~ 90.4%和87.2%~88.3%之间,说明分离株与经典的NDV毒株存在一定的差异.  相似文献   

10.
从四川省两个不同肉鸽养殖场的送检病鸽中分别分离出2株鸽源新城疫病毒(NDV),分别命名为Mianyang12505和sms12。致病性试验表明2株鸽源NDV均为弱毒,但融合蛋白(F)基因序列分析表明2个毒株均含有典型的强毒株F蛋白裂解位点112RRQKRF117;以F基因序列为基础构建遗传发育树,发现2株鸽源NDV属于基因Ⅵ型;F基因突变分析表明,鸽源NDVF基因突变率较大,且基因Ⅵ型和Ⅶ型存在规律突变;核酸和氨基酸序列同源性分析表明,国内鸽源NDV毒株核酸序列同源性为83.5%~99.7%,氨基酸同源性为85.6%~100%,且本研究分离的毒株与JS0722Pi同源性最高。  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.
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   

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.
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   

19.
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   

20.
<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   

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