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木聚糖酶与肉仔鸡小麦日粮代谢能之间当量关系的研究 总被引：7，自引：0，他引：7
酶制剂在家禽营养中的应用逐渐普及,如植酸酶和NSP酶,其中NSP酶已经广泛的应用于麦类基础的家禽日粮中,大多数研究结果都证明了肉鸡小麦日粮中添加NSP酶对生产性能有一定的促进作用。小麦日粮的抗营养作用就在于含有较高水平(1 1 % )的NSP(阿拉伯木聚糖) ,影响肠道食糜黏度,降低营养物质的消化吸收率(明根和朝格图,1 996)。木聚糖酶通过水解饲料中的木聚糖,消除其抗营养作用,从而提高蛋白质、脂肪、淀粉等营养物质的消化率,同时伴随着饲料代谢能的提高(卢铮和张日俊,1 997)。目前已经不再提倡简单地将酶制剂添加到饲料中去的做法,因为… 相似文献
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为了研究低代谢能日粮添加木聚糖酶对AA肉仔鸡生长性能和免疫功能的影响,试验将木聚糖酶添加于玉米-杂粕、小麦-豆粕为主的低代谢能日粮中饲喂AA肉仔鸡,测定木聚糖酶对其生长性能的影响;经玫瑰花环试验测定其对肉鸡细胞免疫功能的影响,借此分析评估肉仔鸡的免疫状态。结果表明:木聚糖酶能显著提高肉仔鸡的生长性能;也能使肉仔鸡外周血T淋巴细胞免疫力升高,尤其是小麦-豆粕日粮中添加木聚糖酶可以显著提高肉仔鸡的免疫功能。 相似文献
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小麦作为猪饲料具有较高的营养价值,小麦日粮中的抗营养因子主要是阿拉伯木聚糖,表现为增加动物消化道食糜黏度,使小麦在畜禽日粮中的应用受到限制。木聚糖酶可有效降解猪日粮中的木聚糖,缓解或消除木聚糖的抗营养因子,稳定饲料品质,提高养分消化利用效率,改善动物生产性能,使小麦日粮在木聚糖酶的作用下达到玉米日粮的效果。本期华南农业大学冯定远教授就木聚糖酶的作用机理,对猪生长性能、消化系统发育、饲粮中养分消化利用的影响进行系统阐述,希望对行业能有所借鉴和参考。 相似文献
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本试验旨在研究复合酶和木聚糖酶在肉鸡低代谢能饲料中的应用效果。试验结果表明,肉鸡前期(0～周)降低饲料代谢能50Kcal/kg使用复合酶或木聚糖酶不会对生产性能造成影响,且使用复合酶效果好于单一的木聚糖酶;后期(4～6周)降能加酶,各试验组采食量与正对照组差异不显著(P>0.05),添加木聚糖酶显著提高了平均日增重(P<0.05),降低饲粮代谢能添加木聚糖酶对肉鸡生产性能无显著影响。 相似文献
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本试验研究小麦-豆粕型日粮中添加不同组合的非淀粉多糖酶对肉鸡生产及营养物质消化代谢的影响。选用1日龄AA肉鸡360羽,随机分为6组,分别饲喂小麦型高能饲粮、小麦型低能饲粮和添加不同酶制剂组合的小麦低能饲粮,每组4个重复,每重复15只鸡。结果表明:小麦型低能日粮中添加木聚糖酶对肉鸡生产性能及表观代谢能没有显著影响;添加木聚糖酶+葡聚糖酶、木聚糖酶+葡聚糖酶+甘露聚糖酶、木聚糖酶+葡聚糖酶+甘露聚糖酶+纤维素酶组合均可显著改善低能饲养肉鸡日增重和饲料利用率、提高其表观代谢能(P0.05),其中以添加木聚糖酶+葡聚糖酶+甘露聚糖酶组合和木聚糖酶+葡聚糖酶+甘露聚糖酶+纤维素酶组合两组对肉鸡生产的效果最好,但不同酶制剂组合间无显著差异(P0.05)。 相似文献
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木聚糖酶在猪饲料中的研究与应用 总被引：2，自引：0，他引：2
小麦作为猪饲料具有较高的营养价值，小麦中的抗营养因子主要是阿拉伯木聚糖，其作用主要表现为增加动物消化道食糜粘度。日粮中添加以木聚糖酶为主的复合酶，可有效消除其抗营养作用，提高猪的生产性能。2001年以来，我国许多地区小麦价格大大低于玉米，使木聚糖酶得到空前规模的应用与发展。作者就近几年来，国内外学者对木聚糖酶在猪饲料中的研究与应用作一综述。 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
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Billinghurst RC Brama PA van Weeren PR Knowlton MS McIlwraith CW 《American journal of veterinary research》2004,65(2):143-150
OBJECTIVE: To determine whether serum concentrations of biomarkers of skeletal metabolism can, in conjunction with radiographic evaluation, indicate severity of osteochondrosis in developing horses. ANIMALS: 43 Dutch Warmblood foals with varying severity of osteochondrosis. PROCEDURE: 24 foals were monitored for 5 months and 19 foals were monitored for 11 months. Monthly radiographs of femoropatellar-femorotibial and tibio-tarsal joints were graded for osteochondral abnormalities. Serial blood samples were assayed for 8 cartilage and bone biomarkers. At the end of the monitoring period, foals were examined for macroscopic osteochondrosis lesions. RESULTS: Temporal relationships were evident between certain serum biomarkers and osteochondrosis severity in foals during their first year. Biomarkers of collagen degradation (collagenase-generated neoepitopes of type-II collagen fragments, type-I and -II collagen fragments [COL2-3/4C(short)], and cross-linked telopeptide fragments of type-I collagen) and bone mineralization (osteocalcin) were positive indicators of osteochondrosis severity at 5 months of age. In foals with lesions at 11 months of age, osteochondrosis severity correlated negatively with COL2-3/4C(short) and osteocalcin and positively with C-propeptide of type-II procollagen (CPII), a collagen synthesis marker. Radiographic grading of osteochondrosis lesions significantly correlated with macroscopic osteochondrosis severity score at both ages and was strongest when combined with osteocalcin at 5 months and CPII at 11 months. CONCLUSIONS AND CLINICAL RELEVANCE: The ability of serum biomarkers to indicate osteochondrosis severity appears to depend on stage of disease and is strengthened with radiography. In older foals with more permanent lesions, osteochondrosis severity is significantly related to biomarker concentrations of decreased bone formation and increased cartilage synthesis. 相似文献