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青贮饲料中乳酸菌代谢及其青贮品质影响研究进展 总被引:6,自引:1,他引:5
在青贮发酵过程中,乳酸菌不同其产酸能力也不同,而且会产生不同的抑菌物质和芳香物质.近年采的研究表明,乳酸菌在青贮饲料发酵过程中会代谢产生乳酸等芳香物质,对青贮饲料的品质有很大影响;乳酸菌还会产生细菌素及其他抑菌物质抑制有害微生物的生长.就青贮过程中乳酸菌代谢及其对青贮品质影响的最新研究进展进行了综述. 相似文献
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在青贮发酵过程中,乳酸菌不同其产酸能力也不同,而且会产生不同的抑菌物质和芳香物质。近年来的研究表明,乳酸菌在青贮饲料发酵过程中会代谢产生乳酸等芳香物质,对青贮饲料的品质有很大影响;乳酸菌还会产生细菌素及其他抑菌物质抑制有害微生物的生长。就青贮过程中乳酸菌代谢及其对青贮品质影响的最新研究进展进行了综述。 相似文献
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青贮发酵过程中,乳酸菌的数量与青贮品质息息相关。添加乳酸菌青贮可以有效提升青贮饲料品质。近年来的研究表明,乳酸菌在青贮饲料发酵过程中会代谢产生大量有机酸、细菌素及其它抑菌物质,可以有效抑制有害菌的生长,防止二次发酵。另外,乳酸菌对饲料中黄曲霉毒素具有降解和抑制作用,大大提高了青贮饲料的安全性。饲喂添加乳酸菌的青贮饲料对奶牛还有益生作用,可以提高产奶量。本文阐述了青贮的原理及制作高品质青贮的必要条件,并总结了在制作青贮饲料时添加乳酸菌青贮对其品质的具体改善效果,以及添加乳酸菌的青贮饲料对奶牛的益生作用及生产性能的影响。 相似文献
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青贮是常用的饲料储存方法之一,添加乳酸菌可以提高青贮饲料环境酸性,抑制病原微生物生长,提高有氧稳定性,提高动物生产性能。使用乳酸菌对饲料进行厌氧发酵能够保持饲料的新鲜度,提高饲料的营养价值,改善适口性。用于青贮的乳酸菌数量和种类会对饲料品质产生不同影响。青贮饲料发酵过程包括有氧阶段、厌氧阶段和稳定阶段等。不同乳酸菌在饲料发酵过程中的不同阶段发挥作用。文章主要介绍了用于饲料青贮的乳酸菌的常见种类及其对青贮饲料发酵品质的影响,为研发优质的青贮微生物添加剂、提高青贮饲料发酵品质提供参考。 相似文献
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青贮微生物及其对青贮饲料发酵品质影响的研究进展 总被引:1,自引:0,他引:1
青贮微生物在饲料发酵过程中起关键作用。无论是牧草表面附着的微生物还是外源添加的微生物菌剂在青贮发酵过程中对青贮微生物的群落结构及其演替过程都起着重要的作用,而青贮发酵过程中微生物的群落结构及其演替过程与代谢产物很大程度上影响着青贮饲料的发酵品质。本文阐述了青贮微生物群落结构,微生物在青贮过程中的演替及其对青贮饲料品质的影响。从目前研究结果来看,不同牧草及同种牧草生长在不同环境中其表面附着微生物存在很大差异。添加乳酸菌对提高青贮品质效果不稳定,还需了解牧草附着微生物特性决定是否需要接种乳酸菌以得到优质青贮饲料。 相似文献
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在青贮发酵过程中占主导地位的微生物是乳酸菌,利用乳酸菌发酵产生大量的乳酸来降低饲料pH值,抑制其中有害微生物的生长,从而可长期保存青贮饲料。而酵母菌能分解饲料中的有机物质,降低青贮饲料的品质。因此,青贮饲料中微生物的种类和数量将决定青贮发酵的效果。试验采用不同培养基、不同培养方法及不同接种方法对青贮饲料中的微生物进行培养。试验结果表明:对乳酸菌进行分离培养时,在添加100mg/l放线菌酮的MRS培养基上,采用涂布法和厌氧培养的方式,其分离培养的效果较好。 相似文献
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本文从青贮饲料的定义及发酵原理,青贮饲料品质的评定,影响青贮发酵品质的因素及解决方案,乳酸菌添加剂在青贮过程中的作用,复合型乳酸菌制剂几个方面论述了如何制作高品质的青贮饲料。 相似文献
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青贮饲料的主要添加剂 总被引:5,自引:0,他引:5
在青贮过程中,正确合理地利用青贮饲料的添加剂可以改变因原料的含糖量及含水量的不同对品质的影响,增加青贮料中有益微生物的含量,可以消除恶劣条件对饲料青贮的影响,提高原料的利用率及青贮料的品质.1 乳酸发酵促进剂1.1 乳酸菌 使用乳酸菌时主要对禾本科牧草及含糖量较低的原料青贮效果较好,对豆科牧草的效果不太明显.一般使用乳酸菌要符合以下条件:①发酵均匀.②植物中的糖可进行发酵.③能满足较强乳酸的生成. 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