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1.
用鸡痘病毒载体表达马立克氏病病毒(MDV)糖蛋白B(gB)基因构建成重组鸡痘病毒(rF-PV)。以MDV GA或Md5和RBIB混合攻毒,在不同品种的鸡中评价rFPV-gB/R单价苗和与火鸡疱疹病毒(HVT)组成的二价苗的免疫保护效力。试验结果表明,MDV疫苗和FPV母源抗体阴性的SPF鸡和母源抗体阳性的商品鸡中,rFDV-gB/R均能提供免疫保护作用,且其中一种商品蛋鸡中rFPV-gB/R与HVT液氮苗或HVT冻干苗结合使用,均有显著的免疫协同保护作用。免疫学研究指出,rFPV-gB/R与常规疫苗一样,可显著地降低疫苗免疫攻毒鸡的病毒血症和羽囊排毒。  相似文献   

2.
用鸡痘病毒载体表达马立克氏病病毒(MDV)糖蛋白B(gB)基因构建成重组鸡痘病毒(rFPV)。以MDV GA或Md5和RBIB混合攻毒,在不同品种的鸡中评价rFPV-gB/R单价苗和与火鸡疱疹病毒(HVT)组成的二价苗的免疫保护效力。试验结果表明,MDV疫苗和FPV母源抗体阴性的SPF鸡和母源抗体阳性的商品鸡中,rFDV-gB/R均能提供免疫保护作用,且其中一种商品蛋鸡中rFPV-gB/R与HVT液氮苗或HVT冻干苗结合使用,均有显著的免疫协同保护作用。免疫学研究指出,rFPV-gB/R与常规疫苗一样,可显著地降低疫苗免疫攻毒鸡的病毒血症和羽囊排毒。  相似文献   

3.
用表达马立克氏病病毒(MDV)Ⅰ型疫苗株CVI988/Rispens 糖蛋白B(gB)基因的重组鸡痘病毒(rF-PV-gB/R)和鸡痘病毒(FPV)疫苗株282E4 免疫1 日龄不同品种的鸡,来评价2 种病毒株的安全性及免疫性。试验结果表明,rFPV gB/R和FPV 282E4 免疫鸡后对FPV 强毒攻击均可提供100% 的保护,对有FPV母源抗体的商品蛋鸡安全无毒性,而对无母源抗体的SPF鸡的毒性则不同。斑点杂交和Southern 杂交证实,rFPV-gB/R 中无氨苄青霉素的抗性基因。  相似文献   

4.
本文对高效表达鸡马立克氏病(MD)血清Ⅰ型疫苗毒株CVI988/Kispem gB基因的重组鸡痘病毒(rFPV—gB/R)和火鸡疱疹病毒(HVT)组成MD二价冻干疫苗时MD超强毒株(vvMDV)Md5和RB1B攻击后的免疫保护效果,实验室免疫效力试验的结果表明,HVT rFPV—gB/R二价冻千苗时超强毒株Md5和RB1B攻击时的免疫保护效果明显优于HVT冻干苗,接近CVI988/Rfispens的水平,本研究证明HVT rFPV—gB/R二价冻干疫苗是一种安全、方便、高效的疫苗。  相似文献   

5.
鸡马立克氏病Z4+HVT二价苗的免疫效力试验   总被引:2,自引:1,他引:1  
用鸡马立克氏病(MD)血清Ⅱ型和Ⅲ型病毒制备了几种二价苗和单价苗。在实验室以高度易感的SPF鸡和商品鸡进行疫苗的免疫效力试验。结果表明,马立克氏病病毒(MDV)血清Ⅱ型毒株和Ⅲ型毒株之间存在协同保护作用。由血清Ⅱ型和Ⅲ型病毒组成的二价苗免疫效果明显优于单价苗。在以SPF鸡进行的免疫效力试验中,Z_4+HVT、SB_1+HVT、HVT、Z_4和SB_1的保护指数分别为78.9、78.6、41.7、46.7、和45.0;在以商品鸡进行的免疫效力试验中,Z_4+HVT、SB_1+HVT、HVT、Z_4和SB_1的保护指数分别为93.9、88.1、64.3、69.4和60.8。我们还用琼扩试验检查了强毒攻击后不同时期鸡羽囊排毒情况,发现Z_4+HVT二价苗抑制排毒的作用要比SB_1+HVT二价苗强。  相似文献   

6.
将表达鸡γ干扰素基因、表达MDV gB基因、共表达MDV gB和鸡γ干扰素基因的重组鸡痘病毒进行组合免疫观察在SPF鸡、狼山鸡中的免疫保护作用。在狼山鸡中随rFPV-gB剂量的减少,保护效力逐渐下降,而在SPF鸡中10^4与10^6PFU的rFPV-gB提供相同的保护效力,但存在减缓增重的副反应;在所有的疫苗组合中,由10^6PFU的rFPV-gB、10^5PFU的rFPV-IFN-Ⅱ和4000PFU HVT组成三价疫苗的保护效力最高且不影响增重,表明鸡γ干扰素既或降低重组鸡痘病毒的减缓增重的副反应,又具有免疫佐剂作用,与重组鸡痘病毒及HVT配合成疫苗是预防MD有效的冻干制剂。  相似文献   

7.
为了评价表达鸡马立克氏病病毒gB基因重组鸡痘病毒(rFPV-gB/R)的遗传稳定性,我们将纯化后的重组病毒在CEF单层上连续传30代,引起细胞病变的速度和形态均未发生明显变化;覆盖含X-Gal的琼脂引起的空斑均为蓝色;间接免疫荧光实验证明rFPV-gB/R中的gB基因始终能稳定表达;序列测定结果表明,重组病毒在细胞上连续传30代、在SPF鸡上连续传5代后,gB基因序列没有发生任何变化;以0、10、20、30代重组病毒制成冻干疫苗进行的实验室免疫效力实验表明,细胞连续传代后rFPV-gB/R仍然保持了原有的免疫原性。可见重组鸡痘病毒gB基因的结构和免疫原性都是高度稳定的。为了评价rFPV-gB/R的生物安全性,我们将rFPV-gB/R通过SPF鸡连续传5代,检测病毒在鸡体的存在部位及其消长、生长繁殖性能和毒力变化;将rFPV-gB/R免疫鸡与未免疫鸡同笼饲养,攻击FPV-102E6强毒,以检测rFPV-gB/R感染鸡的接触传染性。结果显示,rFPV-gB/R在鸡体的存在时间大约为7d,在体内仅存在于接种部位;鸡体传代后痘病毒毒力有一定程度下降,gB基因核苷酸序列未发生任何变化;同居未免疫SPF鸡在痘病毒强毒攻击后全部发痘,可见重组病毒免疫鸡没有接触传染性,能在鸡体内稳定地传代,rFPV-gB/R具有高度的生物安全性。  相似文献   

8.
使用马立克氏病(MD)二价苗或火鸡疱疹病毒苗(HVT)与新城疫(ND)疫苗联合免疫肉鸡和蛋鸡,MD二价苗与ND苗联合免疫组对MD的免疫力离于HVT与ND联合免疫组。各组对ND的免疫力与单独用ND苗免疫比较,没有明显差异。MD二价苗和ND死、活苗联合接种肉鸡,对ND可获终生保护,对MD保护率亦高于HVT免疫组。  相似文献   

9.
马立克氏病(Marek’。Disease,简称MD)是严重危害养鸡业的主要传染病之一。预防接种是控制该病的有效手段。但是近年来在有些以HVT疫苗免疫过的鸡群中,MD发病率仍然较高。本文就以MD单价苗、二价苗和三价苗免疫不同的鸡群所产生的不同效果进行观察与分析。正材料与方法1.二疫苗单价苗为HVT冻干疫苗,病毒为血清皿型HVT-FC126株,由南京生物制品厂生产。二价苗为MDVI型几株和HVT-FC126珠制备的细胞苗,由江苏家禽研究所生产、三价苗为MDV致弱株814株、Z#和HVT-FC126组成的细胞苗,由哈尔滨兽医研究所生产。1.2试验…  相似文献   

10.
传染性喉气管炎新城疫鸡痘重组病毒免疫效力的研究   总被引:1,自引:2,他引:1  
在表达鸡传染性喉气管炎病毒(ILTV)糖蛋白gB基因和新城疫病毒(NDV)F基因的重组鸡痘病毒(rF-PV-gB-F)安全性检验合格后,以5.0×101~5.0×104PFU不同含量按0.1mL/鸡的剂量免疫100只30日龄SPF鸡,30d后分组分别用ILTVWG株和NDVF48E9株强毒进行攻击。免疫鸡抗鸡痘病毒抗体都转为阳性,痘反应和接种剂量有关,重组疫苗的最小反应剂量为50PFU。重组疫苗可以诱发对新城疫和传染性喉气管炎的保护,0.1mL/鸡的接种量在500~5000PFU浓度范围内的免疫效果最好,对于ILTV攻击的发病保护率在70%以上,对NDV强毒攻击的抗死亡保护率可以达到80%,这为进一步考察疫苗的免疫效力试验以及进行田间试验奠定了基础。  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.
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.
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   

18.
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   

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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