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锌是动物机体内的必需微量元素，它自从Tucker和S0lmon（1955）首先证实锌为猪生理所必需物质，缺乏会出现皮肤不完全角化症以来，经众多的研究表明，锌广泛分而于机体组织中，是许多重要酶的组分，参与机体蛋白质的合成和核糖核辞、脱氧核糖核田和其它物质的代射；同时对促进骨骼、角质生长，强化垂体前叶激上的活性，增强机体免疫和抗感染能力等均有良好作用。近年来又发现在断奶仔猪口粮中添加高剂量锌，对减少断奶仔猪腹泻，提高其生长速度有显著效果。为此，本文就高粹在断奶仔猪生产中的应用作一简述，供参考。1高锌的作用机理与使用… 相似文献
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高锌的作用机理及其在仔猪饲粮中的应用 总被引：3，自引：0，他引：3
锌是动物的必需矿物质微量元素之一，现已证明锌参与动物体内300多种酶和功能蛋白的组成。作为生理生化功能最为广泛的微量元素，锌不仅参与DNA、RNA、蛋白质、糖类、脂类、矿物质和维生素的代谢，而且与胰岛素、胰高血糖素、前列腺素、促性腺激素等的功能和活性有关。近年来，研究人员对仔猪饲粮高锌的促生长作用进行了大量研究。结果表明，断奶仔猪饲粮中添加高剂量的锌(2000mg／kg以上)，可改善仔猪生长性能和降低断奶后腹泻率。本文根据国内外学者对仔猪锌营养的研究进展，综述了高锌的作用机理、促生长作用及其影响高锌效果的因素、使用高锌饲粮的注意事项。 相似文献
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锌是体内多种金属酶、激素和胰岛素的组成成分，也是200多种酶的激活因子，参与核酸和蛋白质合成、能量代谢、氧化还原、细胞免疫和体液免疫过程。缺锌时，会导致体内物质代谢紊乱．影响动物的生长、免疫等。在实践中常见低于10kg断奶乳猪发生缺锌症，显示断奶仔猪更容易发生锌缺乏症。国外的众多研究报道，饲料中添加以氧化锌形式的高锌，能防止断奶仔猪缺锌症的发生，并且锌以ZnO的形式用于仔猪腹泻的预防。l断奶仔猪锌缺乏的病因分析1．l断奶仔猪来食饲料中的锋相对不足食奶仔猪在正常情况下一般不会引起锌的缺乏，这是因为仔猪体内锌的… 相似文献
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<正>0引言在养猪生产中,仔猪健康发育与养猪生产效益密切相关。断奶仔猪因生长快、易感疾病等特点需要精心喂养。断奶后仔猪因环境和营养源变化而产生应激,表现为生长缓慢和营养物质吸收效率下降。因此,缓解仔猪断奶应激的功能性饲粮或营养素正成为猪营养学研究的热点。锌是维护畜禽健康和良好营养的重要元素,促进仔猪生长、降低腹泻率、提高免疫力,并具有参与机体抗氧化功能。过去有研究仔猪对硫酸锌、氧化锌、蛋氨酸锌、 相似文献
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高剂量氧化锌在断奶仔猪日粮中的应用试验 总被引：1，自引：0，他引：1
锌是一种重要的微量元素。自发现以来 ,世界各国对其进行了广泛深入的研究 ,特别是近年来高剂量的氧化锌已逐步应用于断奶仔猪日粮。据堪萨斯 (Ｋａｎｓａｓ)州立大学的研究结果报道 ,断奶仔猪饲喂高锌 (310 0ｍｇ/ｋｇ ,氧化锌 )饲粮 ,没有出现腹泻。据Ｈａｌｌ的研究报道 ,喂给断奶仔猪 2 5 0 0～30 0 0ｍｇ/ｋｇ的锌 (氧化锌 )有利于猪的健康与生长。密兹根(Ｍｉｃｈｉｇａｎ)州立大学的最新研究结果认为断奶仔猪饲喂高剂量锌 (30 0 0ｍｇ/ｋｇ ,氧化锌 )有提高生长率的趋势。目前国内关于断奶仔猪日粮使用高剂量氧化锌的研究报道较少 ,… 相似文献
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微量元素锌在肠道中的吸收 总被引：1，自引：0，他引：1
锌是动物体必需的一种微量元素，它因在体内具有广泛的生理生化功能而被称为“生命元素”。锌是多种酶的组成成分，它参与机体蛋白质的合成，脂肪、碳水化合物和维生素等营养物质的代谢；骨骼发育和角质的生成也需要有锌的参与：锌还能增强机体免疫力、抗感染能力及促进创伤愈合。那么，锌是如何进入机体的呢?本文就微量元素锌在动物肠道的吸收过程作一简单综述。 相似文献
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高锌加酸化剂日粮对断奶仔猪腹泻效果试验 总被引：1，自引：0，他引：1
将２８窝２８２头断奶仔猪随机分在四组：１组每千克日粮中添加锌２０００ｍｇ,２组添加柠檬酸１０ｇ,３组添加锌２００ｍｇ和柠檬酸１０ｇ,对照组喂基础日粮作添加高锌和有机酸对断奶仔猪腹泻效果试验。结果表明：腹泻率加锌２０００ｍｇ和柠檬酸１０ｇ组比对照组下降３６．９％,差异极显著（Ｐ〈０．０１）;同时高锌对提高断奶仔猪生产性能和减少腹泻有明显作用,高锌加酸化剂日粮对防制断奶仔猪腹泻有协同作用。 相似文献
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近几年来国内外对高剂量锌在畜禽日粮中的添加效果进行了广泛的研究.据报道,早期断奶仔猪日粮中添加高锌能减少仔猪下痢,提高日增重,改善饲料报酬,并对影响高锌添加效果的因素及其机理进行了一些研究和探讨.目前国内部分早期断奶仔猪饲料中已开始添加高锌.本文仅就国内外高锌在早期断奶仔猪中的研究和应用进展加以综述,供进一步研究和应用参考. 相似文献
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选用40头28日龄断奶约滇陆（YN1）杂交仔猪进行为期5周的试验，试验仔猪随机分为5个组（锌添加量分别为80，240，1000，3000和5000mg／kg），研究锌对断奶仔猪生产性能、免疫器官生长发育及组织锌沉积的影响。结果表明：适量高锌（1000mg／kg和3000mg／kg）能显著提高仔猪生产性能（P〈0．05）：补锌对免疫器官指数无影响（P〉0．05）：高锌增加肝脏、肾脏、趾骨、血清和毛发中锌含量（P〈0．01）：而背最长肌、扁桃体和胸腺锌含量则只有在添加5000mg／kg日粮锌时含量显著上升（P〈0．05）。脾脏锌含量则随着高锌的添加变化差异不显著（P〉0．05）。低锌添加（80mg／kg和240mg／kg）对机体各组织中锌含量无显著影响（P〉0.05）。 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
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Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献