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寡糖作为饲料添加剂是动物营养研究近20年来的热点之一。继抗生素、益生素的研究之后,动物营养学家对寡糖投以极大的关注,其中果寡糖是寡糖最重要的组成部分之一。果寡糖是抗生素的替代品之一,其作用显著优于抗生素及益生素。在日本,果寡糖约有500多种产品,已被视为一种食品,有报道在煎制牛肉时添加果寡糖可以降低不同形式的芳香族胺的形成。在动物饲养中,果寡糖可以促进肠道内有益菌的增生,而抑制有害菌的繁殖,从而改善动物体内的微生态环境、提高动物的免疫力及生产性能。1果寡糖的概况果寡糖(Fructooligosaccharide,FO S)又称为低聚果… 相似文献
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果寡糖（Fructo-oligosaccharides，FOS）是近些年研究较多的一种新型环保添加剂。大量试验表明，它不仅具有促进动物生长发育的功效，而且提高动物免疫机能，促进新陈代谢，从而提高动物的生产性能和经济效益。本文介绍了果寡糖的特性，主要作用机理及其在动物生产中的应用，为进一步开发和利用果寡糖提供依据。 相似文献
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本文以棉子糖系列寡糖为代表综述了天然和合成寡糖对肉鸡生产性能的影响，研究表明天然寡糖对动物健康和生产性能有负作用，但合成寡糖相反，这与寡糖的化学结构，添加量以及动物所处生理阶段有关，饲料中需要合成寡糖，但在深入了解其分子结构基础上，充分合理利用天然寡糖的有益片段，除去有害片段，合理使用天然寡糖或其廉价合成品，更具实际应用价值。 相似文献
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甘露寡糖在反刍动物营养中的研究进展 《畜牧与饲料科学》2015,36(12):32-32
甘露寡糖是一种新型饲料添加剂。大量研究表明,甘露寡糖在改善动物肠道微生态、提高动物免疫力、促进动物生长等方面具有明显作用。然而有关甘露寡糖在反刍动物上的研究较少,主要对甘露寡糖在反刍动物生产上的研究进展作一介绍。 相似文献
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寡糖是由2～10个单糖通过糖苷键连接形成的直链或支链糖类，按其生物学功能可分为普通寡糖和功能性寡糖两大类。普通寡糖可被单胃动物小肠消化吸收，包括蔗糖、乳糖等；功能性寡糖包括果寡糖（FOS）、甘露寡糖（MOS）、寡葡聚糖（GOS）、寡乳糖（Gas）、寡木糖（XOS）、棉子糖、大豆寡糖等，这些寡糖在动物消化道前端不被消化，故称为难消化性寡糖（NDO）。功能性寡糖由于难以被动物体内分泌的消化酶分解，在肠道后段可选择性促进双歧杆菌和乳酸杆菌等有益菌群的增殖及抑制大肠杆菌等有害菌的增殖，从而维持了肠道微生态平衡（Gibson和Roberfroid，1995；Houdijk等．2002：Bielecka等，2002）。国内外的研究表明，功能性寡糖能够提高畜禽生产性能，减少发病率和死淘率（Houdiik，1998；杨曙明，1999；易中华等，2004）。 相似文献
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甘露寡糖作为一种新型的饲料添加剂，能够提高水产动物的生长性能，优化其肠道菌群结构，提高其非特异性和特异性免疫功能，已经成为水产动物营养研究的新热点。本文对甘露寡糖的理化性质，生理功能和研究进展进行了总结，旨在为今后甘露寡糖的进一步研究提供参考。 相似文献
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半个世纪以来，抗生素作为畜禽促生长剂和抑菌药物广泛应用于养殖业，它能显著提高畜禽生产力。但研究发现，长期应用抗生素会使机体产生抗药性和药物残留，甚至会诱发人和动物产生癌变和畸变，危及人类的健康和安全。因而，研制能改善畜禽健康、提高生产性能且安全无毒副作用的饲料添加剂已成为目前的一个开发热点。大量研究表明，甘露寡糖（Mannan Oligosaeeharides，MOS）在动物体内可通过减少肠道病原菌，调节动物免疫反应，提高肠黏膜的完整性，最终提高生产性能，被认为是最有希望的抗生素替代品之一。但不同的寡糖对不同的动物效果不一，来源不同的同类寡糖效果也不—样。用魔芋MOS进行了一系列试验，为进一步验证其效果，进行了MOS饲喂犊牛重复试验。 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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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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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