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1.
正禽白血病是由禽白血病病毒引起的严重危害我国养鸡业的重要肿瘤性疾病。不同亚群的禽白血病病毒可以引起鸡淋巴细胞瘤、髓细胞瘤、血管瘤、成红细胞瘤等多种类型肿瘤发生,A、B亚群主要引起鸡经典的淋巴细胞瘤,J亚群禽白血病病毒主要引起髓细胞瘤、血管瘤为主的肿瘤~([1])。过去十几年给我国养鸡业造成了巨大威胁,而其他亚群的禽白血病病毒引起病例报道较少。近年来,随着各种外在条件的变化,禽白血病病毒不同毒株和不同亚群之间交叉重组时有发生,  相似文献   

2.
<正>禽白血病是由禽白血病病毒引起的禽类的多种类型肿瘤性疾病的总称,该病在临床上表现形式多种多样,包括淋巴细胞性白血病、成红细胞性白血病、成髓细胞性白血病和髓细胞性白血病等。禽白血病/肉瘤病毒群中A、B、C、D、E和J 6个亚群来源于鸡,其中E亚群为内源性病毒,其他的5个亚群为外源性病毒。在20世纪80年代之前,禽白血病病毒亚群的变异都较小。但随后,在美国、以色列和法国等国家的肉鸡中陆续发生J  相似文献   

3.
家禽血管瘤的发生与防制   总被引:2,自引:1,他引:1  
近几年来,与J亚群白血病病毒相关的禽白血病在我国禽群中广泛流行,其中,与禽白血病J亚群病毒(ALV-J)密切相关的血管瘤性疾病在我国蛋鸡群中呈蔓延趋势.本文就血管瘤的病原及发病机理、流行病学、临床症状、病理变化及防制的相关知识作一系统介绍.  相似文献   

4.
1禽白血病的来源 国内J亚群禽白血病主要来源于美国进口种鸡,由于外国血统的引进,使得J亚群白血病在国内蛋鸡、肉鸡均造成感染.而A、B亚群目前还没有明确的追溯证据.由于禽白血病是种禽垂直传播的,因此在种禽选育工作中对该病的控制显得十分重要.  相似文献   

5.
正禽白血病是由禽白血病病毒(Avirus leukosis virus, ALV)引起的禽的淋巴细胞白血病、成红细胞白血病、髓性细胞白血病等多种肿瘤性疫病。宿主范围广,不同品种和品系的禽对病毒的感染差别较大。主要流行A、B、C、D、J、K和E亚群禽白血病,且外源性病毒较内源性病毒传染性和致病性强。目前我国很多地方品种鸡均有不同程度的单独或混合感染A、B、J、K亚群禽白血病。  相似文献   

6.
禽白血病是由反转录病毒(禽白血病/肉瘤病毒群)引起的以造血组织细胞异常增生为特征的肿瘤性疾病.根据病毒囊膜糖蛋白的特性可分为10个亚群(A~J).其中J亚群禽白血病病毒(ALV-J)自1989年英国Payne[1]在肉鸡群中首次发现以来,在世界各地肉鸡群中陆续暴发了J亚群禽白血病.  相似文献   

7.
禽白血病是由禽白血病病毒(Avian Leukosis Virus, ALV)引起的以造血细胞恶性增生为主的一类传染病,包括淋巴细胞性白血病,成红细胞性白血病,成髓细胞性白血病和骨髓细胞瘤病.1988年,Payne等从肉仔鸡中分离出一种新型的禽白血病病毒亚群即J亚群(ALV-J),1997-1998年间,禽白血病J亚群世界范围内的流行,给世界养禽业带来了巨大的经济损失.鸡群感染ALV-J后造成广泛的免疫抑制,从而继发其它病毒和细菌的感染,给生产带来巨大的损失.因此,在未来数年内,研究和控制禽白血病免疫抑制问题可能成为家禽业的主要任务之一.本文就白血病的病原及其产生免疫抑制的危害进行了概述,并且从基因水平上分析了ALV-J引起免疫抑制的主要机理.  相似文献   

8.
为了解禽白血病病毒在商品蛋鸡中的流行情况,试验采用病理剖检、聚合酶链式反应(PCR)以及间接免疫荧光试验(IFA)等方法对送检的疑似禽白血病病毒感染的商品蛋鸡进行了病毒分离与鉴定,并对分离株的致瘤相关基因gp85基因进行测序,与国内外各亚群禽白血病病毒进行对比。结果表明:分离、鉴定到1株J亚群血管瘤禽白血病病毒,命名为FJ0610;分离株gp85基因核苷酸序列同源性在11.5%~94.5%之间,其中与血管瘤禽白血病毒株ZH-08株同源性最高,而与E亚群毒株同源性最低;基于gp85核苷酸序列的系统进化分析表明FJ0610株的gp85序列与ZH-08株的亲缘关系最近。  相似文献   

9.
采用ELISA检测ALV-Ag P27抗原的方法,对崇仁麻鸡禽白血病进行净化,结果表明该方法的净化效果显著。经过一个世代禽白血病的净化,净化种鸡群比非净化种鸡群在存活率、产蛋性能、种蛋受精率以及后代商品鸡生长性能等方面都有较大辐度的提高,可显著提高养殖效益,种鸡群进行禽白血病净化对提高养鸡经济效益意义重大。  相似文献   

10.
为了解禽白血病、禽网状内皮组织增生症和鸡传染性贫血在本地鸡群的感染情况,对宁波市7个区、县的15个鸡群进行了3种疫病4种抗体的血清学检测。结果显示:362份被检血清中,AB亚群禽白血病病毒(ALV-AB)抗体阳性率为55.0%,J亚群禽白血病病毒(ALV-J)抗体阳性率为21.5%,禽网状内皮组织增生症病毒(REV)抗体阳性率为32.0%,鸡传染性贫血病毒(CAV)抗体阳性率为66.8%;15个鸡场AB亚群禽白血病和鸡传染性贫血共感染率为100.0%;12个鸡场共感染了3种免疫抑制性疫病,混合感染率高达80.0%。调查结果表明免疫抑制病在宁波市鸡群中非常普遍。  相似文献   

11.
传染性支气管炎是一种急性、高度接触性传染病,被世界动物卫生组织(OIE)列为B类疫病,对世界养禽业的发展造成了严重威胁.目前,传染性支气管炎的主要预防措施仍然是接种疫苗,但由于传染性支气管炎病毒具有血清型众多、变异速度快且交叉保护性弱等特点,使得传染性支气管炎的防制一直是养禽业面临的重大难题.文章主要对传染性支气管炎病毒的分子生物学特征及其弱毒疫苗的发展历程和免疫策略等方面进行了阐述,以期为新型传染性支气管炎弱毒疫苗的开发及应用提供科学参考.  相似文献   

12.
Infectious bronchitis (IB) is an acute and susceptible infectious disease,which has been classified as B loemia and causes a grave threat to the poultry industry.Now,the primary prevention measures of IB are vaccine inoculation.With the diversity of infectious bronchitis virus (IBV) serotype and easy variation,and the weakness of cross protection,the prevention and control of IB were a major problem in poultry industry.In this ariticle,it summarized the molecular biological characteristics, and the development and immunization strategy of the attenuated vaccine of IB to provide scientific references for the research and application of IB attenuated vaccine.  相似文献   

13.
以4种决明属植物草决明(Cassia obtusifolia)、望江南(C.occidentalis)、伞房决明(C.corymbosa)、双荚决明(C.bicapsularis)为材料,采用盆栽控水试验,设置轻度干旱、重度干旱和正常灌水处理,研究了干旱胁迫对4种决明属植物的叶绿素含量、光合作用参数和叶绿素荧光特性的影响。结果显示,1)干旱胁迫导致4种决明属植物的叶绿素含量下降,望江南的下降幅度最小,说明望江南在水分减少的情况下仍具有较高的光合作用能力,伞房决明的叶绿素含量在3种处理下都趋于最高水平,表明伞房决明光能吸收、转换和传递能力较强;2)干旱胁迫导致4种决明属植物气孔导度(Gs)降低,气孔限制值(Ls)升高,伴随着胞间CO2浓度(Ci)降低,净光合速率(Pn)下降,表明是气孔因素造成的,此后,除草决明外其它3种植物的Ci均升高,Ls均下降,这是非气孔因素造成的;在干旱胁迫下望江南具有较高的光合速率,伞房决明具有相对较高的气孔开放度;3)干旱胁迫导致4种决明属植物的最大荧光(Fm)和光化学效率(Fv/Fm)下降,初始荧光(Fo)上升,表明PSⅡ结构受到破坏或者植物进行了热耗散。光化学淬灭系数(qP)和电子传递速率(ETR)下降,而非光化学淬灭系数(NPQ)上升,说明干旱胁迫对PSⅡ造成伤害,但其能够有效地避免或减轻因PSⅡ吸收过多光能而引起的光抑制和光氧化。望江南表现的最稳定,说明望江南具有较强的抗旱性。  相似文献   

14.
为探讨喹乙醇急性中毒雏鸡血液生化指标的变化情况,。将200只5日龄伊莎公鸡雏随机分为2组,对照组饲喂基础饲粮,试验组饲喂基础饲粮+150mg/kg喹乙醇。在染毒后5、10、15d,对相关血液生化指标进行检测。结果表明,喹乙醇中毒时,在各时间点,试验组血清K+含量均高于对照组,在15d差异显著(P<0.05);试验组血清中Ca2+、PO43-、Na+含量均低于对照组,在15d差异均显著(P<0.05);试验组血清ALB、TP含量均低于对照组,ALB在15d差异显著(P<0.05),TP在10d和15d差异显著(P<0.05);试验组血清ALP、GOT、GPT活性高于对照组,GOT、GPT在15d差异显著(P<0.05)。结果显示喹乙醇中毒能够引起雏鸡相关血液生化指标的改变,喹乙醇有一定的蓄积毒性。  相似文献   

15.
刘鸽 《中国乳业》2021,(12):94-99
对新疆石河子地区某规模化奶牛场的712 头澳系荷斯坦泌乳牛进行乳房炎患病率调查。调查结果显示,40 头奶牛患临床型乳房炎,患病率为5.62%。从剩余的未表现出临床乳房炎症状的672 头奶牛中随机选出180 头奶牛,共682 个乳区(720 个乳区中有38 个瞎乳头),分别进行兰州乳房炎检测(LMT)和乳样体细胞数(SCC)检测。经LMT诊断发现,180 头奶牛中有56 头患隐性乳房炎,患病率为31.11%;经SCC检测发现,180 头奶牛中有60 头患隐性乳房炎,患病率为33.33%。数据分析发现:各乳区患乳房炎阳性率差异不显著(P>0.05),说明各乳区阳性率之间没有必然规律;6岁以上奶牛的乳房炎患病率与2~3岁、4~5岁的患病率相比差异显著(P<0.05),说明6岁及以上奶牛乳房炎的患病率要高于2~3岁、4~5岁奶牛;6胎及以上的奶牛乳房炎患病率与其他胎次之间差异极显著(P<0.01),说明6胎及以上奶牛的乳房炎患病率要远高于1胎、2胎、3胎、4胎、5胎奶牛。  相似文献   

16.
In the present study, 1‐cell stage mouse embryos were cultured with or without glucose, and their development to the blastocyst stage was compared. Embryos cultured in a glucose‐free medium had a higher percentage of development to the 8‐cell stage, and they had higher developmental speeds compared with those cultured in a glucose‐containing medium. The percentages of embryos that developed to the early blastocyst stage, blastocyst stage and expanded blastocyst stage were much lower than those developed in a glucose‐containing medium. This suggests that the culture of 1‐cell stage embryos in a glucose‐containing medium inhibits development at the 8‐cell stage, and that glucose is necessary for blastocyst formation. Previous reports indicate that, from the 1‐cell stage to the 4‐cell stage, glucose inhibits embryo development. In the present study, exposure of early embryos to a glucose‐free medium improved subsequent embryo development, and there was no difference in the percentage of development to the stages ranging from the 8‐cell stage to the expanded blastocyst stage between embryos cultured in a glucose‐free medium from the 1‐cell stage to the 2‐cell, 4‐cell and 8‐cell stage. This indicates that embryo development is improved when a 1‐cell stage embryo is exposed to a glucose‐free medium before and during the 2‐cell stage, and glucose only has an inhibitory effect on embryo development during conversion from the 1‐cell stage to the 2‐cell stage.  相似文献   

17.
Wnt3a在不同毛色羊驼皮肤中的表达和定位   总被引:2,自引:0,他引:2  
本研究旨在探索Wnt3a在羊驼皮肤中的表达与定位.以不同毛色的成年羊驼为研究对象,应用荧光定量PCR技术分析不同毛色羊驼皮肤Wnt3a基因的相对表达量,并运用Western blotting及免疫组织化学法对Wnt3a蛋白在不同毛色羊驼皮肤中进行表达和定位研究.结果:荧光定量PCR结果显示棕色羊驼中Wnt3a mRNA相对表达量是白色羊驼的2.9702倍;Western blotting结果表明,羊驼皮肤组织组蛋白提取物中存在相对分子质量约39 ku的产物,棕色羊驼皮肤平均蛋白表达量显著高于白色羊驼;免疫组织化学结果显示Wnt3a在羊驼皮肤毛囊的根鞘和毛球部呈阳性表达,根据光密度值分析得出Wnt3a在棕色和白色羊驼毛囊中的表达差异显著(P<0.05).通过以上研究显示Wnt3a可能与羊驼毛色形成具有相关性.  相似文献   

18.
A delayed union metacarpal stress fracture was repaired in a horse, using lag-screw fixation in conjunction with dc electrical stimulation. Twelve weeks after surgery, radiographic and scintigraphic evaluations revealed that the fracture line was not discernible and that there was a decrease in radiopharmaceutic uptake, as compared with that in previous bone imaging studies. In this horse, DC stimulation of a delayed union stress fracture in a bone resulted in a healing pattern similar to that in human beings with delayed union fractures when treated with electrical stimulation.  相似文献   

19.
An investigation of a small outbreak of abortion in mixed-age cows in a dairy herd in Somerset produced circumstantial evidence that a leptospire belonging to the Pomona serogroup was the causative agent. Although the initial epidemic involved more than 30 per cent of the herd, agglutination titres did not persist in the majority of animals and bacteriological monitoring produced no evidence that this leptospire could establish endemic infection in dairy cattle. An isolate recovered from the kidney of a cow which aborted was found to be similar to mozdok, a serovar maintained by free-living species in continental Europe, and it is probable that free-living species also maintain the Pomona serogroup organisms that have been isolated in England. Clinical disease caused by infection of domestic stock with Pomona serogroup organisms other than pomona has not been recognised in other countries but this may be because of the presence of endemic infection with pomona, a serovar that causes a very similar clinical and serological response.  相似文献   

20.
Blood coagulation is a basic physiological defense mechanism that occurs in all vertebrates to prevent blood loss following vascular injury. In all species the basic mechanism of clot formation is similar; when endothelium is damaged a complex sequence of enzymatic reactions occurs that is localized to the site of trauma and involves both activated cells and plasma proteins. The reaction sequence is initiated by the expression of tissue factor on the surface of activated cells and results in the generation of thrombin, the most important enzyme in blood clot formation. Thrombin converts soluble fibrinogen, via soluble fibrin monomers, into the insoluble fibrin that forms the matrix of a blood clot as well as exerting positive-feedback regulation that effectively promotes additional thrombin generation that facilitates the rapid development of a thrombus. Both spontaneous and trauma-induced haemorrhagic episodes can develop in all mammals with inherited or acquired abnormalities in one or more of the coagulant proteins. Experimental studies with plasma from a wide range of species have led to the conclusion that there are extensive differences in the rates of thrombin generation and fibrin formation among species. However, current evidence suggests that at least some of these quantitative differences are likely due to the use of non-species specific laboratory reagents. Although the individual proteins involved in the procoagulant pathways exhibit similar functions in all animals, differences in amino acid sequence cause incomplete homology and varying degrees of immunological cross-reactivity for the same protein across species.  相似文献   

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