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如何合理应用氨基酸添加剂 总被引：2，自引：0，他引：2
过去普遍采取提高饲料蛋白质水平来补充必需氨基酸在动物体内的需要量 ,目前由于氨基酸工业的发展 ,常用单体氨基酸作为饲料添加剂使用 ,以减少高蛋白水平饲料的用量。氨基酸添加剂可改善和平衡日粮氨基酸比例 ,提高日粮蛋白品质 ,降低蛋白质用量。如在畜禽饲料中添加赖氨酸和蛋氨酸 ,可以使基础饲料低蛋白化 ,改善氨基酸平衡等 ,提高畜禽饲养的生产性能 ,提高瘦肉率。但是氨基酸作为添加剂使用有着一些基本的原则 ,所以随着集约化经营和适度规模畜牧业迅速发展 ,氨基酸饲料添加剂的应用技术也显得愈来愈重要。1 氨基酸添加于饲料的方法氨… 相似文献
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准确测定饲料氨基酸消化率（ＡＡＤ）已成为动物营养学评定饲料氨基酸生物效价的主要研究课题之一。ｓｉｂｂａｌｄ建立的强饲法，用于测定饲料ＡＡＤ的方法，由于未考虑鸡盲肠微生物对饲料氨基酸消化率的影响，可能导致低估饲料ＡＡＤ。鸡盲肠是消化道微生物主要活动场所，对氨基酸有降解作用。用切除盲肠的鸡，进行氨基酸利用率的研究，更能真实反映饲料蛋氨酸（Ｍｅｔ）的利用率。本研究的目的，是通过测定去盲肠与不去盲肠的两组试验鸡内源Ｍｅｔ排泄量和Ｍｅｔ排泄量及所测饲料中Ｍｅｔ表观消化率和真消化率的差异，来探讨盲肠微生物主… 相似文献
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1啄癖的发生原因
在市场经济情况下，许多养鸡户为了节省饲养成本，在全价饲料中加入玉米，导致日粮就失去了全价性，饲料中的蛋白质、氨基酸、微量元素的配比不合理，因此导致了啄癖的发生。 相似文献
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合成氨基酸的特殊营养作用中国农业科学院研究生院伍喜林随着对氨基酸在动物体内的代谢机理、营养生理功能的深入研究，氨基酸分析技术及人工合成氨基酸方法的革新，使合成氨基酸的应用从节约蛋白质饲料而深入到降低畜禽应激、减轻畜禽排泄物导致的环境污染、充分满足畜禽... 相似文献
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1影响因素饲料中蛋白质和氨基酸不足时,会导致蛋鸡卵巢发生萎缩,卵泡发育受阻,从而使产蛋量减少,因此产蛋期要保证蛋鸡日粮中蛋白质和氨基酸的含量。蛋鸡产蛋率大幅度上升期间,如果维生素添加量不足,会导致母鸡机体生理代谢发生紊乱而影响产蛋。因此,从开产到产蛋高峰阶段,应该适当加大饲料中多种维生素的添加量来满足蛋鸡的需要。钙、磷 相似文献
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近年来，蛋白原料价格不断上涨．给饲料成本带来不少的压力。目前，饲料工业正逐步朝着绿色、健康、安全方向发展，为了降低饲料成本，节约蛋白质原料．降低动物应激．减少排泄物对环境的污染．人们利用理想蛋白质模式．通过添加合成氨基酸来配制低蛋白质日粮。但合成氨基酸的应用．会导致日粮中支链氨基酸特别是异亮氨酸和缬氨酸的缺乏。Sohwedel等（2006年）研究表明．在泌乳期平均日失重1．20kg的高产母猪玉米-豆粕型日粮中．缬氨酸为第3限制性氨基酸。因此．支链氨基酸的合理配比对于猪的正常生长发育、泌乳、免疫功能等都起着非常重要的作用。 相似文献
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鱼体组织中蛋白质一般占干重的65％-75％。饲料蛋白质在鱼类肠道中水解成氨基酸后被吸收，用来合成新组织及组织蛋白更新。因此，饲料中蛋白质含量不足或氨基酸不平衡，则鱼类生长很快就会减慢或停止，体重下降（Lee等，2001）。同时，饲料中过量的蛋白不但会增加成本，还会导致氨氮排放增加（Tibbetts等，2000），从而影... 相似文献
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为了建立高效饲料氨基酸含量的检测方法，本研究以大豆、豆粕、鱼粉和混合饲料为饲料原料，采用微波水解-氨基酸自动分析法、近红外光谱分析法和高效液相色谱法测定饲料氨基酸相关参数，对其结果进行对比分析。结果表明：高效液相色谱法的水解温度为160℃，水解时间为20 min，对饲料氨基酸组成和稳定性的影响程度较小，偏差程度小，而另外2种检测方法对饲料氨基酸的组成和稳定性的影响程度较大|说明高效液相色谱法的精准度高，检测时间短，快速精准，可用于大豆、豆粕、鱼粉和混合饲料中氨基酸含量的检测。但高效液相色谱法存在一定的缺陷，饲料中氨基酸含量的测定方法应根据实际情况来确定。
[关键词]饲料氨基酸|不同检测方法|比较研究 相似文献
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氨基酸是最重要的一类营养物质，有着重要的生理功能，随着可利用氨基酸模式在配方设计中的应用，氨基酸饲料添加剂已越来越成为一种重要的饲料添加剂，科学的认识氨基酸和合理的应用氨基酸饲料添加剂，对提高饲料的质量水平和经济效益有很大的作用。 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