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在仔猪日粮中其能量饲料主要为玉米,而青海省不是玉米主产区,其主要农作物是小麦。小麦比玉米的蛋白质和赖氨酸含量高30%以上,可利用磷的含量比玉米高,色氨酸含量约为玉米的3倍,矿物质以及维生素含量与玉米几乎没有差别,但消化能含量低于玉米。用小麦代替玉米时,可降低饲料的成本,提高经济效益,缓解能量饲料短缺的压力。由于小麦中非淀粉多糖含量高, 相似文献
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玉米是当前饲料企业最常用、也是最难控制品质的原料之一。通过玉米营养价值评估研究和笔者实践认为:①玉米营养价值评估重点考虑能量和蛋白质的利用价值,玉米的能量评估主要与脂肪和淀粉的含量有关,此外,还要关注玉米蛋白质利用对日粮营养平衡的不利影响;②玉米品质控制主要从感官、营养和卫生等指标控制,其中利用近红外检测营养指标可以快速预测玉米营养价值,并有助于精准利用玉米;③在猪配合饲料生产中,采购玉米时应注意产地和储存时间,这是玉米成本控制的机会,粉碎和膨化工艺可以提升玉米在配合料的营养价值,同时也可改善玉米的颗粒外观、糊化度和和适口性,提高饲料的综合品质。 相似文献
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饲料中蛋白质含量的高低是反映该饲料品质好坏最重要的指标之一,所以不管是对单一饲料,全价饲料还是浓缩饲料,都必须检验其蛋白质含量。检验单一饲料的蛋白质含量,可以按质论价,为合理配方提供依据;检验全价饲料和浓缩饲料的蛋白质含量,可以发现配方和加工中存在的问题,确保产品质量,提高饲养效果。因此饲料蛋白质的测定对 相似文献
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提高玉米饲用价值的途径 总被引:2,自引:0,他引:2
我国的玉米总产量占世界的 1 / 6。玉米总产量的 70 %以上用作饲料 ,占饲用谷类总量的 50 % ,是主要饲料原料。但现行玉米生产仍多沿袭食用粮生产方式 ,存在若干弊端。根据畜牧生产规律和需求 ,以农牧结合方式安排玉米生产 ,充分挖掘畜禽转化玉米的潜力 ,提高玉米的饲料报酬 ,具有重要的经济意义。1 推广饲料玉米品种我国蛋白质饲料资源匮乏 ,扩大高蛋白玉米种植面积 ,能够缓解蛋白质饲料的紧张局面。由于玉米总产量大 ,在饲料配方中所占比例高达 50 %以上 ,提高玉米籽实的蛋白质含量 ,可提高玉米所供蛋白质数量。玉米籽实中蛋白质含量每增… 相似文献
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用玉米作为家禽配合饲料的能量原料是我国使用的典型配方。玉米的短缺和高价,对生产者来说就意味着饲料成本的提高。生产者应考虑应用价格较为低廉的谷物来抵消玉米价格的升高。近些年来,随着小麦产量的不断提高,价格走低,小麦在家禽饲料中的应用越来越广泛。小麦的代谢能是玉米的90%。用肉仔鸡、产蛋鸡和火鸡做的试验表明,小麦可以作为家禽的主要能量饲料。但小麦有其特殊性,在家禽配合饲料中应注意其合理使用。一、小麦的特点小麦蛋白质高于玉米,赖氨酸含量较高,而苏氨酸的含量与玉米相当。用小麦替代玉米作能量饲料时,配合饲… 相似文献
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饲料配方、饲料形态、抗营养因子、水、温度、噪声、光照都影响采食和饲料转化率。饲料蛋白质和能量水平表1列出了肉仔鸡采食不同水平的蛋白质和能量饲料后的表现。采食量随着能量的增加而减少。低蛋白质饲料增重慢,高蛋白质饲料增重快。低蛋白质饲料增重慢的原因是食入相同的饲料,其中蛋白质含量低的缘故。食入高蛋白质低能量的饲料生长慢的原因是有部分蛋白质补充体内能量的不足而消耗掉了。所以,肉仔鸡食入高能量高蛋白质饲料生长速度最快。矿物质的补充在饲料中添加食盐将增进食欲和提高效益。表2列出了在肉仔鸡玉米-豆饼日粮中添加… 相似文献
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育肥牛饲料种类很多,且各具特点,因此必须互相搭配,配制一个合理的平衡日粮,才能满足育肥牛营养需要。 一、基础饲料 1.精饲料:主要有粮谷类、饼粕类和糠麸类。其特点是体积小、营养高、粗纤维含量低。根据蛋白质含量又分为能量饲料和蛋白质饲料。①能量饲料。包括玉米、高粱、大麦、糠麸等,尤以玉米为主要能量饲料。②蛋白质饲料。包括豆饼(粕)、葵籽粕、玉米蛋白粉等。 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