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《养殖与饲料．饲料世界》2020,(1)
畜禽饲料营养价值评定的数据信息是饲料数据库中的关键指标之一,客观准确地评价畜禽饲料营养价值、建立数据库是确定畜禽养殖过程中准确营养需要量的重要依据,同时也是优化畜禽养殖饲料配方、降低畜禽养殖成本和节能减排的重要理论和方式。畜禽饲料营养价值评价方法主要有化学分析法、消化试验法、平衡试验法、饲养试验法和屠宰试验法等。本文主要介绍了畜禽饲料原料离体消化试验法,旨在为畜禽饲料营养价值的评定提供参考。 相似文献
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试验利用体外产气法评定反刍动物饲料的营养价值。对花生藤、木薯渣、柠檬酸渣和甜叶菊渣4种原料进行体外发酵试验,通过测定各种原料的24h累计产气量、干物质(DM)降解率和细菌氮含量来评定其对反刍动物的营养价值。试验结果表明:花生藤、木薯渣、柠檬酸渣和甜叶菊渣的24h累计产气量分别为93.50、106.25、117.25和54.33ml;DM降解率分别为34.76%、48.34%、24.66%和33.63%;细菌氮含量分别为1.48、1.10、1.54和1.59mol/(g·ml)。总体来看,这几种饲料可以作为反刍动物的新型饲料资源加以推广利用,而且用体外产气法评定反刍动物饲料的营养价值是可行的。 相似文献
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奶牛饲料体外产气评定预测模型及其改进 总被引：1，自引：0，他引：1
奶牛的生产性能很大程度上受制于饲料的营养价值。饲料营养价值评定需要测定其化学成分及消化特性，包括体内法（in vivo）、半体内法（in sire）和体外法（in vitro）。由于采用体内产气法可以测定发酵产物，考虑了饲料可溶但不发酵的部分，避免了消化道流量、指示剂、微生物指示剂和动物个体差异而导致的误差，同时具有估测动态发酵的优势，以其省时，省力，费用较低，成为评价反刍动物饲料营养价值的常用方法。饲料营养成分对体外评定法中体外消化率（IVTD）、产气量及挥发性脂肪酸产量的估测存在一定影响。 相似文献
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利用体外产气法评定反刍动物饲料的营养价值 总被引：2，自引：0，他引：2
本试验利用体外产气法评定反刍动物饲料的营养价值.对花生藤、木薯渣、柠檬酸渣和甜叶菊渣4种原料进行体外发酵试验.通过测定各种原料的24 h累计产气量、干物质(DM)降解率和细菌氮含量来评定其对反刍动物的营养价值.试验结果表明,2 g花生藤、木薯渣、柠檬酸渣和甜叶菊渣样品的24 h累计产气量分别为93.50、106.25、117.25 mL和54.33 mL;DM降解率分别为34.76%、48.34%、24.66%和33.63%;细菌氯含量分别为1.48、1.10、1.54mol/(g·mL)和1.59 mol/(g·mL).总体来看,这几种饲料可以作为反刍动物的新型饲料资源加以推广利用,而且用体外产气法评定反刍动物饲料的营养价值是可行的. 相似文献
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《养殖与饲料．饲料世界》2018,(12)
本文简述了饲料营养价值的评定方法(化学成分分析法、体内营养价值评定法、体外消化实验法)及饲料营养成分(蛋白质、碳水化合物、脂肪)对猪只生长性能的影响。 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