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国标１０８１８－８９第二篇中规定了５０％氯化胆碱粉剂中氯化胆碱含量的测定方法，此法繁琐、费时，尤其是蒸发甲醇一步耗时较长，且需要回收装置。本人认为氯化胆碱可直接溶于冰乙酸中，且少量赋形剂（麸皮、米糠、玉米芯等）在溶液中不会影响滴定终点的颜色变化，因此可以直接用冰乙酸溶解进行快速测定，此法在实验中得到了较理想的结果。１ 实验方法１．１ 国标法 称取８０℃下干燥３ｈ的样品０．７ｇ左右（准确至０．０００２ｇ），置于２５０ｍｌ锥形瓶中，加４０ｍｌ甲醇，充分摇动３０ｍｉｎ后过滤，再分别用２０ｍｌ、１５ｍｌ… 相似文献
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１ＧＢ／Ｔ１３８８５－９２中测定方法及计算公式简述１１测定方法准确称取２ｇ～５ｇ试样（精确至００００１ｇ）于硬质玻璃烧杯中，炭化、灼烧、溶解、定容至１００ｍｌ，干过滤，得试样分解液。预混合饲料样品称取１ｇ～３ｇ（精确至００００１ｇ）加入１００?.. 相似文献
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本研究的目的是测定在肉鸡日粮中不同水平的虾粉（ＳＭ）替代豆粕（ＳＢＭ）的效果。试验１：ＳＭ粗蛋白替代肉鸡日粮中０，１０，２０，３０和４０％的ＳＢＭ粗蛋白；试验２：ＳＭ粗蛋白替代肉鸡日粮中０，６０，８０和１００％ＳＢＭ粗蛋白。体重、累计耗料和饲料转化率（饲料：增重）试１：４９天和试２：４２天均为每周测定一次，死亡率每日统计，胴体重和屠宰率的确定以屠宰后冷却２４小时的冷却胴体为基础。在试１体重、饲料消 相似文献
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按照“国标”规定,对于粮食、油料、饲料、油脂及粮油食品的水分检测,其操作程序是:(一)、调节烘箱温度在105±2℃;(二)、烘干烘盒(或称量皿、下同)至恒重W_0;(三)、称取试样,烘至恒重时烘盒与试样共重W_1;(四)、烘干试样,烘至恒重时烘盒与试样共重W_2; 相似文献
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国标规定饲料原料中水分含量测定方法，分析时间至少3～4小时，对于购进饲料特别是原料需要及时投入生产使用，分析时间显得较长，如能缩短分析检测的时间，则有利于更好地指导生产。本实验利用现有的多功能红外水分仪(红外干燥器与系列天平连成统一系统)，通过实验选出最佳的条件测定，分析时间可减少到0.5～1小时，实现了快速测定，并得到了较理想的结果。1 实验方法1.1 国标法其原理是试样在105±2℃烘箱中，在常压下烘干，直至恒重，逸失的重量为总水分。(方法略，可参考国标法“饲料中水分的测定”)1.2 快速法其原理是用红外线射到试样… 相似文献
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<正> 饲料级L-赖氨酸盐含量测定是根据国标GB8245—87来确定的。但实际测定中,我们发现测定的结果与国标不一致。在国标中采用非水滴定法,将试样预先在105℃干燥至恒重,称取干燥试样0.2克进行测定,样品干燥的目的是为了去除水分,否则水分过高时,指示剂变色终点将不清晰,测得的结果会不准 相似文献
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三黄种鸡蛋重和蛋形指数对孵化率的影响 总被引：7，自引：0，他引：7
本试验选取３８周龄三黄种鸡蛋９９０枚，分别测定其蛋重和蛋形指数（短径／长径），采用４×４两因子交叉分组设计，将蛋重分成Ａ１（５０ ｇ以下）、Ａ２（５０．１～５５ ｇ）、Ａ３（５５．１～６０ ｇ）和Ａ４（６０．１ ｇ以上）四个水平，将蛋形指数分成Ｂ１（０．７２以下）、Ｂ２（０．７２１～０．７６）、Ｂ３（０．７６１～０．８０）和Ｂ４（０．８０１以上）四个水平，然后进行交叉分组，以研究不同蛋重和蛋形指数对种蛋孵化率的影响。结果表明，蛋重Ａ２（５０．１～５５ ｇ）和Ａ３（５５．１～６０ ｇ）受精蛋孵化率显著高于Ａ１和Ａ４（Ｐ ＜ ０．０５），且Ａ２、Ａ３间差异不显著（Ｐ ＞ ０．０５） ；蛋形指数在Ｂ２（０．７２１～０．７６）范围内，受精蛋孵化率极显著高于Ｂ１、Ｂ３和Ｂ４（Ｐ ＜ ０．０１）。故蛋重在５０．１～６０ ｇ、蛋形指数在０．７２１～０．７６范围内，受精蛋孵化率最高。 相似文献
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泰和乌骨鸡、余干黑鸡及其培育品种常规肉质、组织学特性和化学成分分析 总被引：2，自引：0，他引：2
１材料与方法１．１试验鸡的饲养方法、营养水平等详见本刊上期。１．２测定项目和方法１．２．１常规肌肉品质测定 肉色：屠宰后１－２ｈ，取胸肌肉按５级分制评分图评定。 肌肉大理石纹：取胸肌，置０～４℃冰箱存放２４ｈ，对照大理石纹标准评分图进行评定。 肌肉 ｐＨ值：宰杀后 ４５ｍｉｎ内用携带式 ｐＨ仪测定。 系水力：剥离刚宰杀鸡的胸肌皮肤，切取胸大肌（上１／３）处鲜样５ｇ，置于分析天平称重，然后放在上、下各１８层吸水性能好的卫生纸中，用钢环压缩仪加压３５ｋｇ，持续５ｍｉｎ，随即称取加压后的肉样重，计算系水力、… 相似文献
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为测定条纹鲈对饲料中赖氨酸需要量进行了两次试验。试验饲料含粗蛋白４２％，含消化能１３．４ＭＪ／ｋｇ。试验１饲料赖氨酸含量分别为９．２ｇ／ｋｇ、１４．１ｇ／ｋｇ、１４、６ｇ／ｋｇ、１９．９ｇ／ｋｇ、２１．０ｇ／ｋｇ，试验２饲料含赖氨酸分别为１４．８ｇ／ｋｇ、１８．１ｇ／ｋｇ、２１．３ｇ／ｋｇ、２４．５ｇ／ｋｇ、２７．６ｇ／ｋｇ、３０．９ｇ／ｋｇ。测出鱼体增重、特定生长率、饲料转换率和表观蛋白质利用率随饲料中赖氨酸含量增加至２０ｇ／ｋｇ而提高。试验１鱼体增重和特定生长率回归分析表明，条纹鲈对饲料赖氨… 相似文献
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斑节对虾对饲料中维生素Ｄ的需要量为测定斑节对虾对饲料中维生素Ｄ的适宜需要量进行了２８周的投饵试验。实验１饲料中添加麦角钙化醇和胆钙化醇０、０．１、０．５、２．５、１２．５、６２．５ｍｇ／ｋｇ饲料，投喂平均体重０．１９±０．０２ｇ的幼虾；实验２在饲料中... 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