共查询到20条相似文献,搜索用时 62 毫秒
1.
酵母培养物对肉鸡生产性能和饲料利用率的影响 总被引:1,自引:0,他引:1
<正>酵母培养物作为一种新型的功能性添加剂,可以有效地缓解动物生产中的各种应激。其中含有100多种酵母发酵后产生的代谢产物,这些代谢产物协同作用能够有效地刺激寄生在动物胃肠道内微生物细菌的代谢活性,提供给它们最自然和最全价的营养底 相似文献
2.
3.
微生态制剂的安全性探讨 总被引:2,自引:0,他引:2
微生态制剂主要针对宿主动物胃肠道的菌群,通过外源添加活菌或补给对目标菌种有促生长作用的寡糖,以获得目标菌种在宿主动物胃肠道的优势地位,而目标菌种在宿主动物胃肠道中代谢的强化对动物机体本身产生的营养或非营养性作用,对动物自身代谢起到促进作用。 相似文献
4.
5.
胃肠道菌群的变化在动物健康和疾病中扮演重要角色,越来越多的研究证据将机体的免疫系统与胃肠道菌群联系了起来。其主要机制可能是菌群紊乱导致菌群-免疫互作失调,营养代谢与能量调控失衡,免疫系统受损,最后诱发疾病。围产期奶牛面临维持机体正常生理代谢的严峻挑战,奶牛在围产期容易感染多种疾病,给牧场带来了严重的经济损失。最近的研究表明,围产期奶牛瘤胃菌群紊乱是导致生产性疾病发生的重要诱因,胃肠道菌群与宿主黏膜免疫系统之间的互作在维持胃肠道动态平衡和抑制炎症中起着关键作用。本文综述了围产期奶牛胃肠道菌群变化特征及胃肠道黏膜免疫系统组成,并讨论了菌群与黏膜免疫互作机制在维持奶牛健康中发挥的重要作用,最后介绍了菌群紊乱与免疫失衡介导的奶牛生产性疾病,旨在为探索围产期奶牛饲养管理及疾病防控提供新思路。 相似文献
6.
《饲料与畜牧》2017,(23)
仔猪断奶是养猪生产过程中很关键的一个环节,断奶给小猪在同一时间带来了多方面的应激,从而影响胃肠道健康。肠道健康是保证动物生产性能和健康的一个重要决定因素。断奶后肠道菌群的数量、组成和多样性受到众多相关联因素的影响,比如营养(抗生素、不同的饲料添加剂、原料等)、消化性、环境(内和外)、疾病(临床和亚临床)、应激等。仔猪断奶后支持其生长速度达到最佳的一些方案包括:最大化采食量和日粮消化率,不损伤肠道健康;给肠道提供营养维持肠道壁的结构和吸收功能;稳定肠道菌群,最小化非有益菌的增殖;促进仔猪免疫系统的发育。如今,营养性添加剂成为一种最大化采食量和最终优化性能的可靠方案。全发酵的酵母培养物是包含无活性酵母细胞和代谢产物的复杂产品。许多研究表明,饲料中添加酵母培养物对反刍动物和猪有益,可以改善动物的生长速度、产奶量、氮平衡和营养素的消化。本文作者综述了饲料中添加酵母培养物对断奶仔猪生长性能、养分消化率、血液生化指标和肠道健康的影响。 相似文献
7.
8.
9.
仔猪断奶是养猪生产过程中很关键的一个环节,断奶应激会影响其胃肠道健康。断奶后支持其生长速度达到最佳的一些肠道健康方案包括:最大化采食量和日粮消化率;给肠道提供营养维持肠道壁的结构和吸收功能;稳定肠道菌群,最小化非有益菌的增殖;促进仔猪免疫系统的发育。如今,营养性添加剂成为了一种最大化采食量和最终优化性能的可靠方案。全发酵的酵母培养物是包含无活性酵母细胞和代谢产物的复杂产品。许多研究表明,饲料中添加酵母培养物对反刍动物和猪有益,可以改善动物的生长速度、产奶量、氮平衡和营养素的消化。本文就饲料中添加酵母培养物对断奶仔猪生长性能、养分消化率、血液生化指标和肠道健康的影响进行综述。 相似文献
10.
动物胃肠道中栖息着大量微生物,这些微生物通过代谢产物参与调控宿主新陈代谢、生理免疫和发育过程等。深入了解胃肠道微生物及代谢产物的调控机制,有利于人们采用相应技术手段促进胃肠道健康发育,提高动物生产性能。文章综述了胃肠道微生物产生的不同种类的代谢产物,介绍了这些代谢产物在调控宿主发育中的作用及其机制,以期为通过营养途径调节微生物代谢产物促进动物胃肠道发育提供理论依据。 相似文献
11.
12.
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
13.
14.
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
15.
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
16.
17.
18.
19.
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
20.
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