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非淀粉多糖(NSP)是谷物饲料中的主要抗营养因子包括,纤维素、半纤维素、果胶和抗性淀粉等.非淀粉多糖分为不溶性非淀粉多糖(如纤维素)和可溶性非淀粉多糖(如β-葡聚糖),可溶性非淀粉多糖可直接与水分子作用增加食糜黏性,具有明显的抗营养作用. 相似文献
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1日粮纤维的种类日粮纤维是结构性多糖、非结构性多糖、木质素,以及一部分细胞壁镶嵌蛋白质和矿物质等组成的不均一混合物,是非淀粉多糖(NSP)和木质素的总和。NSP中的β-葡聚糖、阿拉伯木聚糖、果胶、甘露聚糖等以氢键松散地与纤维素、木质素及蛋白结合,溶于水,称水溶性非淀粉多糖或可溶性纤维,大多数NSP均为水溶性的淀粉多糖。以酯键、酚键、阿魏酸、钙离子桥等共价键或离子键牢固的和其他 相似文献
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植物细胞壁包含纤维素、半纤维素和木质素等,纤维素和半纤维素是植物细胞壁最适合被利用的优质成分。非淀粉多糖(NSP)是指不包括淀粉在内的1种复合多糖,也是1种细胞壁多糖。它是除木质素外纤维结构中最重要的成分,纤维对家禽肠道功能调节起到重要作用。目前,微生物领域注重纤维在家禽生产性能、机体健康以及肠道菌群均衡调控等机制的研究。文章首先叙述NSP在家禽生产中的应用研究,探讨NSP在家禽生产性能、机体健康以及肠道菌群平衡中存在的意义,总结其在畜牧生产应用中存在的问题并提出相应的解决方法,旨在为促进家禽生产性能与肠道健康的相关研究提供参考。 相似文献
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麦类作物非淀粉多糖酶研究进展 总被引：1，自引：0，他引：1
玉米是我国目前配合饲料中主要的能量饲料 ,每年我国玉米的供给仍有较大缺口。麦类植物作为世界重要粮食作物 ,具有适应性广、产量稳定、易于储存等特点 ,较玉米也有季节性价格优势 ,所以麦类作物日益受到国内外饲料厂家的重视。然而 ,麦类作物中的抗营养因子 ,主要是非淀粉多糖 (NSP)含量较高 ,限制了它在单胃动物饲料中的广泛应用。1 麦类作物中的非淀粉多糖NSP ,也称可溶性非淀粉多糖 (SNSP) ,是植物组织中除淀粉外所有多糖类的总称。这类抗营养物质主要是β -葡聚糖和阿拉伯木聚糖、纤维素、果胶、甘露糖。NSP在单胃动物胃肠道内… 相似文献
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为了评价玉米、小麦、豆粕、小麦麸等的NSP提取物及纤维素的发酵特性,以采食无抗生素日粮的肉仔鸡盲肠微生物为菌源,通过体外发酵试验比较短链脂肪酸(SCFA)的产量及产生速率。结果表明:小麦NSP提取物的SCFA产量及生成速率最大;豆粕NSP提取物次之,第6、122、4 h的SCFA总产量分别为小麦NSP提取物的65.38%、65.07%、71.76%;玉米NSP提取物和小麦麸NSP提取物紧随豆粕NSP提取物之后,第6、12、24 h的SCFA总产量分别为小麦NSP提取物的61.53%、57.53%、62.75%和55.77%、44.52%、45.10%;纤维素的可发酵性最差,第12、24 h的SCFA总产量仅为小麦NSP提取物的10.96%～14.90%。由此可见,5种NSP的可发酵性的顺序依次为小麦NSP>豆粕NSP>玉米NSP>小麦麸NSP>纤维素。此外,上述NSP发酵产物SCFA组成比例均以乙酸为最多,其次为丙酸,丁酸最少;随着发酵时间的增加,丁酸比例逐渐增加,多数发酵底物在第24 h产生丁酸的比例明显增多。 相似文献
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为探索日粮纤维素水平和环境温度对实验大白鼠日增重、消化道和体成分的影响,选择60只实验大白鼠,用高纤维素日粮非淀粉碳水化合物(NSP占24.6％)和低纤维素日粮(NSP占4.8％),在3种环境温度下(16℃,24℃,32℃)进行了试验。结果表明,冷应激(16℃)可降低实验大白鼠的生长效率和体脂肪。在3个水平环境温度下,高纤维素日粮可使大白鼠的日增重分别降低19.76％、13.01％和12.36％;饲料报酬分别降低21.05％、16.00％和10.71％。日粮纤维素和环境温度均可影响大白鼠的消化道的相对重量和长度,再对内脏器官(肝、心、肾脏)的相对重量没有明显的影响。 相似文献
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营养学家对日粮纤维的研究已有数百年之久,但对其定义尚未完全统一,VanSoest（1970）提出了中性洗涤纤维和酸性洗涤纤维的概念,并根据公式计算出了纤维素、半纤维素的量;Cummings（1981）把日粮纤维看成是一种非淀粉多糖（NSP）和木质素的总和。 相似文献
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日粮中的胍尔豆胶和纤维素分别作为可溶的和不可溶的非淀粉多糖（NSP）来源。对照日粮含有14％的玉米淀粉，7％胍尔豆胶、7％纤维素和7％胍尔豆胶加7％的纤维素的日粮是通过加入NSP替代对照日粮中玉米淀粉（wt／wt），采用2×2因素处理。研究目标是确定胍尔豆胶和纤维素是否改变了：①消化物在小肠和总肠道中通过的速度；②能量和粗蛋白质的消化率，消化物的特性和回肠中的微生物菌群；③血浆葡萄糖和多肽浓度；④生长猪的短期主动采食和生长性能。在试验1中，在12头猪（体重为27．0±1．5kg）的回肠安装了T形套管，并且用于第2阶段转变的设计中，每种日粮有6个观察结果。每个阶段包括18d：12d的适应期，然后是2d的粪便，3d的消化物和1d的静脉血收集阶段。在试验1中， 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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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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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
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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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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