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常用的秸秆饲料化学处理方法包括酸化、碱化、氨化、氧化及它们相互结合后的复合处理等。现主要介绍碱化、氨化两种方法,1碱化处理碱化处理就是在秸秆中加入一定比例的碱溶液,促使木质素与纤维素、半纤维素分离,使纤维素及半纤维素部分分解,细胞膨胀,结构疏松,提高膨胀力与渗透性,破坏木质素与纤维素之间的联系,提高秸秆中含氮物质和潜在碱度,从而提高秸秆的营养价值和饲用效果。一般来说,各种农作物秸秆均可作碱化处理。最常用的有玉米秸秆、小麦秸秆、稻草、大豆秸秆等。经过碱化处理的秸秆容易消化吸收,消化率可提高20%左右,可直接饲喂牛… 相似文献
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<正> 作物的秸秆主要是由植物的细胞壁组成。细胞壁的基本成分是纤维素、半纤维素及木质素。纤维素和半纤维素可以通过瘤胃微生物的作用为反刍动物消化利用,加上细胞的内容物,从理论上说,占秸秆于物质80%以上的成分是可以被消化利用的。但是由于纤维素、半纤维素在细胞壁中是与木质素、硅等以复合体的形式存在,使得实际消化率一般只有40%。将秸秆进行氨化处理,可以提高秸秆的消化率,从而提高秸秆的营养价值。其基本原理如下:首先,氨的水溶液——氢氧化铵呈碱性,它对秸秆的碱化作用可以使纤维素、半纤维素与木质素分离,引起细胞壁膨胀,结构变得疏松,使秸秆易于消化,其次,氨与有机物形成醋酸铵,是一种非蛋白氮化合物,是反刍家畜瘤胃微生物的营养源;它能 相似文献
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曹征贵 《上海畜牧兽医通讯》1995,(4):30-31
氨化饲料是将氨化剂,如氨水、尿素等,按一定比例加入秸秆饲料中,充分拌匀,在密封的条件下,经过一定时间的氨化处理,以提高秸秆饲料的营养价值和适口性。秸秆饲料的主要营养成分是粗纤维,粗纤维中含有纤维素、半纤维素和木质素。其中纤维素和半纤维素可以被牛羊等反刍家畜消化利用,还有部分纤维素与木质素紧密结合,难于被消化利用。氨化可以破坏纤维素与木质素表面之间的结合,并使少量木质素溶解,纤维素和半纤维素表面保护层结构改变,细胞壁膨胀,纤维软化,从而提高粗纤维的消化率。由于秸秆对氨有吸附作用,所以氨化还可以提高秸秆饲料中游离氨的含量,增加秸秆饲料中的粗蛋白质。 一、氨化饲料的制作 1.氨化原料 相似文献
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纤维素是玉米秸秆中的高值成分,其结构与结晶特性是衡量纤维素品质的重要指标,故该文分别采用2种常用碱:氢氧化钠和氢氧化钙对秸秆进行处理,并用FTIR法、X射线衍射(XRD)等方法考察其纤维结构与结晶程度。结果表明:碱化处理都能打破秸秆中纤维素、半纤维素和木质素间的氢键,降低木质素含量,增加半纤维素含量,但氢氧化钠碱化处理纤维素含量高于氢氧化钙处理组;去灰处理可以显著降低木质素与半纤维含量,增加纤维素的聚合度。FTIR光谱显示,纤维素结构中具有-OH基团,C-O在纤维素纤维Ⅰ和纤维素Ⅱ上有拉伸。C-O键振动显示葡萄糖残基围绕糖苷键向纤维素Ⅱ旋转的变化,4%氢氧化钠的浓度处理后玉米秸秆纤维素结晶程度可以达62.7%。 相似文献
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白腐真菌在农作物秸秆中的研究与应用 总被引:3,自引:0,他引:3
秸秆是反刍动物粗饲料的重要来源,但秸秆本身特有的细胞壁结构使其不能被反刍动物充分降解利用。主要原因是秸秆细胞壁中的木质素与纤维素、半纤维素以坚固的酯键紧密地镶嵌在一起,限制了消化酶对细胞壁及细胞内容物的消化作用。与物理、化学等处理方法相比,利用微生物处理秸秆,具有投资少,操作简便,不污染环境等优点。在微生物处理中,尤以白腐真菌处理秸秆效果最佳,能真正降解细胞壁,切断木质素与纤维素、半纤维素之间的酯键,释放出纤维素和半纤维素,然后被反刍动物的瘤胃微生物降解利用,从而提高秸秆的利用率和营养价值。 相似文献
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1 鸡对粗纤维的消化率鸡饲料中的粗纤维包括纤维素、部分半纤维素和木质素;其中又分可溶性纤维(果胶、β——葡聚糖、阿拉伯糖基木聚糖等)和不可溶性纤维(纤维素、木质素和某些半纤维素)。鸡消化道内不分泌消化这些纤维的酶,因此,不能消化这些纤维。但是,在鸡的盲肠内有能产生纤维 相似文献
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秸秆微贮是通过加入发酵剂,在密闭的厌氧条件下,促进秸秆纤维素、半纤维素和木质素的分解,改善秸秆的适口性,提高其消化率,并增加营养。加入“华巨秸秆微贮宝”高活性发酵菌种,使秸秆中能分解纤维素的菌数大幅度提高,在适宜温度、湿度和密闭的厌氧条件下,秸秆中的纤维素、半纤维素和木质素大量降解,产生糖类,继而又被转化成乳酸和挥发性脂肪酸,使pH值下降到4.5~5.0,抑制有害菌和腐败菌的繁殖。经微贮后,微生物秸秆发生了很大的变化,使秸秆转化成优质的粗饲料,不但提高了饲用价值,而且使其不发生腐败,可以长期贮存饲喂。“秸秆微贮宝”处理农作物秸秆,具有产量高、成本低、增重快,无毒害等特点,可以作为一种处理秸秆的新技术,生产的饲料广泛应用于草食家畜的饲养。 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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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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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