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维生素E是机体内具有广泛生理功能的重要脂溶性维生素和营养性抗氧化剂,广泛存在于体内储脂器官和生物膜上,具有免疫调节、阻止自由基对组织攻击和维持膜结构的稳定等重要作用。有关维生素E缺乏对雏鸡红细胞影响方面的研究未见有文献报道。本试验用人工建立的维生素E缺乏症雏鸡模型,通过对雏鸡红细胞G-6-PD活性和血红蛋白(Hb)含量的检测,旨在探讨维生素E缺乏对雏鸡红细胞的影响,为揭示维生素E缺乏对雏鸡红细胞的损伤机制提供依据。 相似文献
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细胞凋亡是生物有机体在进化过程中形成的一种主动性细胞死亡方式,它受细胞外微环境和细胞内遗传物质的调控.透射电镜下观察发现,维生素E缺乏雏鸡免疫细胞具有典型的凋亡特征[1],但其凋亡机制尚不清楚.p53是一种促凋亡基因,bcl-2是一种抗凋亡基因,二者在细胞凋亡过程中具有重要的调控作用.维生素E缺乏对雏鸡脾脏淋巴细胞凋亡基因p53和bcl-2mRNA表达的影响未见有文献报道.本研究通过建立维生素E缺乏雏鸡模型,采用半定量RT-PCR法检测脾脏淋巴细胞内p53和bcl-2mRNA表达水平,旨在揭示维生素E缺乏雏鸡淋巴细胞凋亡的基因调控机制. 相似文献
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试验旨在研究饲粮中维生素E缺乏对雏鸡生长性能、脾脏组织和脾脏淋巴细胞形态结构、脾脏淋巴细胞凋亡相关蛋白和基因表达水平的影响。选取1日龄雄性雏鸡160羽,随机分为2组,饲粮维生素E缺乏试验组的预混料中不添加维生素E,对照组额外添加维生素E(30 mg/kg),每组各80羽,每组10个重复,每个重复8羽,试验期40 d。结果表明:试验组雏鸡平均日增重低于对照组(P<0.05),耗料增重比高于对照组(P<0.05);试验组雏鸡脾脏组织和脾脏淋巴细胞中维生素E含量低于对照组(P<0.05);试验组雏鸡脾脏组织和脾脏淋巴细胞结构出现损伤;试验组雏鸡脾脏淋巴细胞中Caspase-3活性高于对照组(P<0.05);试验组雏鸡脾脏淋巴细胞中Bcl-2的mRNA表达量低于对照组(P<0.05),p53和Caspase-3的mRNA相对表达量高于对照组(P<0.05)。由此可见,饲粮中维生素E缺乏将导致雏鸡生长性能显著降低;维生素E缺乏通过提高脾脏淋巴细胞中Caspase-3活性,影响Bcl-2、p53和Caspase-3基因表达诱导脾脏淋巴细胞凋亡。 相似文献
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雏鸡,主要是所患的脑软化症,渗出性素质及吐绶鸡雏、鸭雏所患的肌营养不良症是一种常发的疾病。因而必须掌握早期诊断维生素缺乏症的方法。经专家们研究已知用维生素可以确保家禽红细胞不受羟尿酸溶血而保持稳定。我们还研究了.氏及氏(1948)等人的报道,据称,在大鼠和家兔中由于维生素E在机体中的缺乏而降低了红细胞对羟尿酸溶血的抵抗力,这种生物现象表明维生素E在细胞膜的构造和机能上,尤其是在类脂化合物的部分起着制约作用。 相似文献
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<正>1维生素E在蛋种鸡生产中的应用1.1维生素E对鸡繁殖机能的影响维生素E与鸡繁殖性能密切相关。维生素E能通过调节垂体前叶分泌促性腺激素,调节鸡性功能。公鸡缺乏维生素E时睾九变性萎缩,精子运动异常,甚至不能产生精子;母鸡卵巢机能下降。种蛋所含的维生素E对于保证胚胎正常发育是必需的。种鸡可通过受精卵向雏鸡转移维生素E,卵黄囊阶段雏鸡(1~5日龄)所需的维生 相似文献
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鸡维生素E与硒缺乏症的防治 总被引:3,自引:0,他引:3
维生素E和硒是鸡生长发育过程中的重要物质,在生理上具有一定的协同作用,具有抑制不饱和脂肪酸氧化的作用,以保护生物膜结构免遭新陈代谢产生的过氧化物的氧化破坏。维生素E和硒缺乏会引起机体广泛的功能障碍,主要表现为脑软化症、渗出性素质和白肌病。一、病因1.饲料发霉变质、维生素E和硒添加不足或搅拌不匀,都易于造成缺乏症。2.维生素E与硒之间有一定的互补关系,任何一方的缺乏,都会造成机体对另一方的需要量增加,因此两者往往同时发生缺乏,单一缺乏较少见。3.鸡患球虫病、慢性消化道疾病、肝胆功能障碍时,会影响维生素E的吸收和转运,… 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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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
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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