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牛病毒性腹泻病诊断方法的研究进展 总被引:9,自引:0,他引:9
牛病毒性腹泻病毒(Bovine viral diarrhea virus.BVDV)也称牛病毒性腹泻一黏膜病病毒(Bovine viral diarrhea-mueosal disease virus,BVD—MDV),在分类学上属黄病毒科(Flaviviridae),瘟病毒属(Pestivirus)BVDV与属内的猪瘟病毒(Classical swine fever virus.CSFV)及羊边界病毒(Border disease virus,BDV),在血 相似文献
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<正>猪瘟(Classical swine fever,CSF)是由猪瘟病毒(Classical swine fever virus,CSFV)引起的猪的一种高度接触性传染病,其流行广、传染性强、致死率高,所以国际兽疫局将之列为A类传染病。我国从20世纪50年代起广泛应用猪瘟兔化弱毒疫苗预防注射,基本上控制了猪瘟的流行。近年来,猪瘟的流 相似文献
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猪瘟诊断和防制研究进展 总被引:9,自引:0,他引:9
猪瘟(Classical swine fever,CSF)是严重威胁养猪业、具有重要经济意义的病毒性疾病之一,被国际兽疫局(OIE)列为A类的15种传染病之一。其特征是小血管壁变性,内脏器官多发性出血、坏死和梗塞。该病的病原是猪瘟病毒(CSFV),CSFV在分类上属于黄病毒科(Flaviviridae)瘟病毒属(Pesti-virus),同属的还有牛病毒性腹泻病毒(Bovine viral diarrhea virus,BVDV)和绵羊边界病病毒(Border disease virus,BDV), 相似文献
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猪瘟又称经典猪瘟(Classical Swine Fever,CSF),是由猪瘟病毒(Classical swine fever virus,CSFV)引起猪的高度致死性、接触性传染病,是世界粮农组织和各国政府密切关注的主要传染病之一。多年来一直使用兔化弱毒疫苗株免疫,免疫效果一直都很好,但是近些年来,我国猪瘟的流行形势和发病特点已经发生了很大的变化,尤其是妊娠母猪带毒综合征、仔猪胎盘垂直传播及先天免疫耐受,同时还存在其它多种非典型的发病特点。 相似文献
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猪瘟病毒(Classical swine fever virus, CSFV)与牛病毒性腹泻病毒、羊边界病病毒、长颈鹿瘟病毒均为黄病毒科,瘟病毒属的成员,其基因组为单股正链RNA,大小约12300个核苷酸,其5^+端非编码区由373个核苷酸组成,3^+端非编码区约由229~244个核苷酸组成。开放阅读框编码一个大约3900氨基酸残基的多聚蛋白,该多聚蛋白在翻译过程中和(或)翻译后,在病毒编码的蛋白酶和宿主细胞酶的作用下,分解成为结构蛋白和非结构蛋白。[第一段] 相似文献
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猪瘟病毒E2基因在昆虫细胞中的分泌表达及活性检测 总被引:2,自引:0,他引:2
猪瘟病毒(Classical swine fever virus,CSFV)E0和E2囊膜糖蛋白是CSFV主要保护性抗原蛋白,均能诱导机体产生CSFV的中和抗体,保护机体免受强毒的攻击。尤其是E2糖蛋白,既是人们研究CSFV新型疫苗的主要对象,也是建立CSFV血清学检测方法的首选抗原,同时还是研究CSFV抗原变异的主要区域。鉴于E2基因在CSFV感染、复制和免疫方面的重要作用,因此一直是猪瘟病毒研究的热点。 相似文献
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魏静 《四川畜牧兽医学院学报》2009,(4):28-32
在现代法律秩序中,商会自治规范是制定法的基础和必要的补充,甚至在某些方面替代了制定法;商会自治规范主要包括商会组织规范、行为规范、惩罚规范以及争端解决规范等;其效力仅及于其内部成员;商会自治规范和制定法之间存在冲突,但也存在整合的基础。 相似文献
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本文概述了猪的毛色类型、猪的毛色遗传模式,着重综述了猪毛色基因分子基础的研究进展,指出存在问题并就未来发展方向做了思考。 相似文献
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REASONS FOR PERFORMING STUDY: Centesis of the bicipital bursa using an 8.9 cm long spinal needle has been reported but the alternative of employing a 3.8 cm long hypodermic needle requires validation. OBJECTIVE: To compare the efficacy of 2 different methods of centesis of the bicipital bursa and to evaluate the usefulness of ultrasonographic imaging to determine the location of solution administered when centesis of the bursa is attempted. METHODS: For Trial 1, 6 clinicians, who had no previous experience of centesis of the bicipital bursa, attempted to inject a solution composed of an aqueous radiopaque contrast medium and physiological saline solution (PSS) into the bicipital bursae of 2/12 horses using the previously described distal approach to inject one bursa and a proximal approach to inject the contralateral bursa. The bicipital tendon and bursa were examined ultrasonographically before and after injection; and both shoulders were examined radiographically to identify the location of the medium. In Trial 2, another 6 clinicians, also with no previous experience of centesis, repeated Trial 1, using 6 horses, but the radiopaque contrast medium was mixed with air instead of PSS. RESULTS: Accuracy of centesis using the proximal approach was 39% and that of the distal approach 28%. Ultrasonographic examination of the shoulder allowed the location of solution and air to be accurately predicted in all 12 shoulders examined. CONCLUSIONS: Clinicians who have had no previous experience performing centesis of the bicipital bursa are unlikely to be successful in centesis using either approach. Radiographic examination after injecting a radiopaque contrast medium may be necessary to assess the success of centesis especially if bursal fluid is not obtained during centesis. Injecting air along with the radiopaque contrast medium provides more accurate ultrasonographic confirmation of centesis and better radiographic definition than does injection without air. 相似文献
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Effects of size of ingestively masticated fragments of plant tissues on kinetics of digestion of NDF
Ingestively masticated fragments were collected and sized via sieving. Different sizes of esophageal masticate and ruminal digesta fragments, and ground fragments of larger masticated pieces were incubated in vitro, and undigested NDF remaining at intervals of up to 168 h of incubation was determined. The ruminal age-dependent time delay (tau) for onset of digestion of NDF was positively correlated (P < 0.004) with the mean sieve aperture estimated to retain 50% of the fragments between successive sieve apertures (MRA). Degradation rate of potentially degradable NDF (PDF) and level of indigestible NDF were not related (P > 0.10) to MRA of masticated and ground fragments. Estimates of tau were positively related to MRA, with slopes of bermudagrass < corn silage < ruminal fragments of corn silage. It was concluded that fragment size-, and consequently, ruminal age-dependent onset of PDF degradation of a mixture of different fragment sizes results in an age-dependent rate of degradation of the more rapidly degrading of two subentities of PDF. Models are proposed that assume a tau before onset of simultaneous degradation of PDF from two pools characterized as having gamma-modeled age-dependency and age-constant rates. The ruminal age-dependent pool seems to be associated with the faster-degrading pool, and its rate parameter increases with range in MRA in the population of fragments. Conceptually, the ruminal age-dependent rate parameter for PDF degradation seems to represent a composite of several effects: 1) effects of the size-dependent tau; 2) range in MRA of the population of ingestively masticated fragments; and 3) subentities of PDF that degrade via more rapid age-dependent rates compared with subentities of PDF that degrade via age-constant rates. The estimated fractional rates of ruminative comminution of ingestively masticated fragments (0.060 to 0.075/h) were of a magnitude similar to the mean fractional rates of PDF digestion (0.030 to 0.085/h), which implies that ruminative comminution may be first-limiting to fractional rate of PDF digestion. The in vivo roles of ingestive and ruminative mastication of fragments on PDF degradation must be considered in any kinetic system for estimating PDF digestion in the rumen. These results and others in the literature suggest that the rate of surface area exposure rather than intrinsic chemical attributes of PDF may be first-limiting to degradation rate of PDF in vivo. 相似文献
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以国际标准强毒R株人工感染非免疫产蛋鸡,定时扑杀,分别从鼻窦、眶下孔、气管、肺、气囊、卵巢和输卵管分离MG,并收集感染鸡所产蛋分离MG。结果表明,人工感染48小时后上、下呼吸道及肺已被全面感染,96小时气囊已被感染,120小时输卵管已能分离到MG,卵巢始终分离不到MG。人工感染鸡自144小时便能在其所产蛋中分离出MG。药物治疗能在72小时内消除感染,油乳剂苗则需24天后逐渐降低蛋内MG分离率,药物卵内注射、种蛋药浴、高温处理均能杀死卵内MG,但以研制的种蛋浸泡剂药浴效果为最好。 相似文献