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半胱胺不同添加方式对育肥猪胴体品质及血液生化指标的影响 总被引:1,自引:0,他引:1
动物体内几乎所有的激素都直接或间接参与生长的调节,而其中最重要的是由下丘脑-垂体-靶腺构成的神经内分泌生长轴。生长激素是该调控的核心,它能够促进肌肉组织蛋白质的合成,抑制脂肪组织葡萄糖的摄入和脂肪的合成。生长抑素(SS)是由神经系统和胃肠道产生的,它对单胃动物的生长激素(GH)、甲状腺素(T3、T4)、胰岛素等代谢激素起抑制性调节作用。半胱胺(CS)是辅酶A的组成成分,可破坏SS分子的二硫键,解除SS对GH等激素的抑制,从而促进动物的生长发育。然而,CS对SS的作用具有剂量和时间的依赖性,随着使用时间的延长,其效应逐渐减弱,一般… 相似文献
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文浩 《上海畜牧兽医通讯》2003,(6):17-17
生长激素可调节动物体内的营养分配 ,促进组织蛋白合成 ,减少脂肪沉积 ,提高增重速度和饲料转化率。研究表明 :生长激素 (GH)的合成和分泌受下丘脑生长激素释放因子(GRF)和生长抑素 (Somatostation ,SS)的双重控制 ,GH的释放量取决于这两种肽类的兴奋和抑制程度。生长抑素是由神经系统和胃肠道产生的 ,它对单胃动物的生长激素 (GH)、甲状腺素 (T3、T4 )和胰岛素等代谢激素起抑制性调节作用。Szabo等 (1981)报道 ,口服半胱胺 (Cysteamine ,CS)能有效降低大鼠下丘脑、胃和十二指肠的SS免疫活性。因此 ,通过半胱胺对生长抑素的影响 ,有… 相似文献
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半胱胺不同添加方式对育肥猪胴体品质及血液生化指标的影响 总被引:5,自引:0,他引:5
动物体内几乎所有的激素都直接或间接参与生长的调节.而其中最重要的是由下丘脑-垂体-靶腺构成的神经内分泌生长轴,生长激素是该调控的核心它能够促进肌肉组织蛋白质的合成.抑制脂肪组织葡萄糖的摄入和脂肪的合成.生长抑素(SS)是由神经系统和胃肠道产生的它对单胃动物的生长激素(GH)、甲状腺素(T3、T4),胰岛素等代谢激素起抑制性调节作用。 相似文献
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半胱胺在畜牧生产中的应用 总被引:4,自引:0,他引:4
动物的生长受到多种激素的调节,生长激素、甲状腺激素(T3、T4)、胰岛素和性激素均对动物生长起着重要的作用,但起核心作用的激素是生长激素(GH)。在动物体内生长激素的生成、释放受到下丘脑生长激素释放因子(GHRF)和生长抑素(SS)的双重调节,GHRF促进GH的分泌,SS抑制GH的分泌。研究表明,半胱胺(Cysteamine,CS)能够有效降低生长抑素的活性,提高生长激素、胰岛素、甲状腺激素等激素的含量,促进畜禽的生长,在畜牧生产中具有良好的应用前景。 相似文献
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半胱胺对滩羊血清中几种激素水平的影响 总被引:2,自引:0,他引:2
生长抑素(SS)耗竭剂——一半胱胺(cysieamine,CS),即β-巯基乙胺,是CoA的组成成分,相当于半胱胺酸的脱羧产物。据研究,CS能使动物饥体组织SS免疫活性明显下降、血液中SS浓度降低及GH均值和基线水平升高。半胱胺通过消耗体内SS,促进大鼠、兔、肉用仔鸡、猪和羊等动物生长,提高饲料转化率的研究已经比较深入,但CS对宁夏滩羊生长相关激素的影响的研究还很少。现就CS对滩羊血清中生长激素(GH)、 相似文献
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动物的生长发育受神经内分泌系统的调节,其中最重要的是由下丘脑-垂体-靶腺构成的神经内分泌生长轴(the somatotmpic axis)。生长激素(Growth Hormone,GH)是该调控的核心,它能够促进肌肉组织蛋白质的合成,抑制脂肪组织葡萄糖的摄入和脂肪的合成。生长抑素(Somatostatin,sS)是由神经系统和胃肠道产生的,它对单胃动物的生长激素(GH)、 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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乳酸杆菌作为益生菌广泛用于人和动物.本文综述了乳酸杆菌改善宿主健康的机制.乳酸杆菌可通过产生抗菌物质如乳酸、过氧化氢、细菌素,或者通过竞争营养或肠道黏附位点来抑制致病菌;通过诱导黏附素的分泌或阻止细胞凋亡而增强肠道的屏障功能,从而保护肠道.文章重点讨论了乳酸杆菌表面成分(表面蛋白、脂磷壁酸和肽聚糖)与肠道受体(C型凝集素受体、Toll样受体和Nod样受体),阐述了他们结合后启动免疫调节信号,调控肠道免疫功能以发挥改善健康作用的机制. 相似文献