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1.
Energy and protein sources are of prime importance for ruminants as they stimulate microorganisms in the rumen and enhance the productive functions of the animals. Cassava roots in the form of dry cassava chips or pellets as energy sources and dried cassava leaves and cassava hay as protein sources have been used successfully in ruminant rations. These uses of cassava could provide year-round feed which results in a high yield and good quality of milk and contribute to a more lucrative dairy and beef cattle enterprise, especially for small-holder dairy farming systems. There are many other available feed resources in the tropics of potential use in ruminant feeding and particularly in the development of food-feed-systems that are not only beneficial for human and animals but also for the environment.  相似文献   

2.
Animal agriculture has been an important component in the integrated farming systems in developing countries. It serves in a paramount diversified role in producing animal protein food, draft power, farm manure as well as ensuring social status-quo and enriching livelihood. Ruminants are importantly contributable to the well-being and the livelihood of the global population. Ruminant production systems can vary from subsistence to intensive type of farming depending on locality, resource availability,infrastructure accessibility, food demand and market potentials. The growing demand for sustainable animal production is compelling to researchers exploring the potential approaches to reduce greenhouse gases(GHG) emissions from livestock. Global warming has been an issue of concern and importance for all especially those engaged in animal agriculture. Methane(CH_4) is one of the major GHG accounted for at least 14% of the total GHG with a global warming potential 25-fold of carbon dioxide and a 12-year atmospheric lifetime. Agricultural sector has a contribution of 50 to 60% methane emission and ruminants are the major source of methane contribution(15 to 33%). Methane emission by enteric fermentation of ruminants represents a loss of energy intake(5 to 15% of total) and is produced by methanogens(archae) as a result of fermentation end-products. Ruminants' digestive fermentation results in fermentation end-products of volatile fatty acids(VFA), microbial protein and methane production in the rumen. Rumen microorganisms including bacteria, protozoa and fungal zoospores are closely associated with the rumen fermentation efficiency. Besides using feed formulation and feeding management, local feed resources have been used as alternative feed additives for manipulation of rumen ecology with promising results for replacement in ruminant feeding. Those potential feed additive practices are as follows: 1) the use of plant extracts or plants containing secondary compounds(e.g., condensed tannins and saponins) such as mangosteen peel powder, rain tree pod; 2) plants rich in minerals, e.g., banana flower powder; and 3) plant essential oils, e.g., garlic, eucalyptus leaf powder, etc. Implementation of the-feed-system using cash crop and leguminous shrubs or fodder trees are of promising results.  相似文献   

3.
玉米是奶牛舍饲的主要能量饲料来源之一,而蒸汽压片技术是一项目前较为成熟的日粮加工技术,主要通过机械的湿热加工方法改变原料物理形态和营养物质的化学结构,广泛应用于反刍动物日粮中。蒸汽压片处理工艺中的蒸汽压力、温度和处理时间会影响压片产品的容重和淀粉糊化度,进而影响其饲喂效果。研究发现,经蒸汽压片处理的玉米可有效提高其淀粉消化率,加快瘤胃内的发酵速度,改变瘤胃发酵模式,促进瘤胃微生物蛋白合成,有利于维持瘤胃pH及瘤胃内环境的稳定。也有研究表明,蒸汽压片玉米饲喂奶牛后,对其采食量没有明显影响,但可以提高产奶量,改善乳成分,从而提高奶牛的产奶性能。作者对蒸汽压片玉米技术及其在奶牛生产中的应用研究进展进行综述,以期为蒸汽压片玉米在中国奶牛生产中的合理使用提供参考。  相似文献   

4.
植物提取物调控反刍动物瘤胃发酵的研究进展   总被引:4,自引:0,他引:4  
植物提取物中的挥发油、皂苷、生物碱、萜类等化学物质具有抗菌、促生长、提高免疫力和抗氧化等功能。近年来研究发现,植物提取物还可以调控反刍动物瘤胃发酵模式,提高氮存留,减少甲烷排放的功能,因此,植物提取物作为调控反刍动物瘤胃发酵的一种重要添加剂得到了广泛的研究与应用。目前国内外的学者已经在有效植物品种的筛选和植物提取物作用机理、剂量效应等方面的研究取得了较大进展。文中就目前植物提取物对反刍动物瘤胃发酵调控的最新研究进展作一综述,为我国开展植物提取物作为反刍动物瘤胃发酵调控添加剂的研究提供参考。  相似文献   

5.
Comparative aspects of plant tannins on digestive physiology, nutrition and microbial community in sheep and goats are discussed in the context of differences due to feed intake, digestibility, utilization of nutrients and microbial community. The purpose of this review was to present an overview of the potential benefits of tannin‐containing diets for sheep and goats and specie differences in their response to tannins. It is well established that moderate level of tannins in the diet (3%–4% tannins DM) can precipitate with soluble proteins and increase protein supply to the sheep, but comparative aspects of tannin‐containing diets in sheep and goats on animal performance, digestive physiology, rumen microbial changes and potential benefits to sustainable animal production by those compounds have received little attention. In addition, developing plant‐based tannin‐containing diets for control of rumen microbiota and rumen fermentation (e.g., methane gas) would be expected to have a greater impact on the ruminant health, productivity and emission of greenhouse gasses. The positive impacts of the plant tannin compounds mainly depend on their influence on the gut microbiome diversity and ability to generate fermentation end products (short‐chain fatty acids) that have diverse biological roles. Diets which contain optimal levels of tannins have potential benefits for sustainability of small ruminant production systems. However, there is a need for an improved understanding of the utilization of tannin‐containing forages to improve their management. This implies investigations of animal responses to tannin‐containing forages or browse species and, in particular, a better understanding of the interactions that can arise between sheep and goats on digestion, DMD, rumen fermentation and microbial community changes. This knowledge could help to improve current feeding systems in terms of efficiency of feed use and environmental impacts (reduce methane gas production) and thus contribute to the development of a sustainable sheep and goat production.  相似文献   

6.
幼龄阶段是反刍动物生长中非常重要的阶段,这一时期的营养供应、生长发育状况和瘤胃发育程度决定了其成年后的生产性能和繁殖效率。由于幼龄阶段消化代谢系统发育不完善且具有极强的可塑性,此阶段日粮的营养水平,尤其是蛋白质和中性洗涤纤维(NDF)水平,在反刍动物发育过程中发挥着非常重要的作用。在生产实践中,营养供给不足或超量供给都会影响幼畜的生长发育及健康状况,这种情况甚至会伴随其一生。而幼龄反刍动物日粮中蛋白质和纤维水平对生长性能和胃肠道发育的调节具有决定性的作用。适量提高日粮中蛋白质水平,可提高幼龄反刍动物的生长发育程度,并由于饲料中瘤胃微生物可利用氮浓度的提高而提高了营养物质消化率和瘤胃的发育。在保证精饲料充足的情况下,提高日粮中NDF水平可提高幼龄反刍动物开食料的采食量,提高生长性能和促进瘤胃发育,同时也伴随着营养物质消化率的提高。但由于试验动物或原料来源不同,在相关试验中仍存在不同的试验结果。为此,作者针对日粮中不同蛋白质和NDF水平对幼龄反刍动物生长发育、营养物质消化率和瘤胃发育的影响,以及出现不同试验结果的原因进行总结和探讨,以期为解决幼龄反刍动物的饲养管理问题、提高其饲养效率提供理论依据。  相似文献   

7.
饲用酶制剂在反刍动物营养中的应用进展   总被引:1,自引:0,他引:1  
一般情况下,在瘤胃中粗饲料细胞壁组分的消化利用率较低,由于其复杂紧密的结构限制了动物对粗饲料的利用。因此,在反刍动物生产中提高粗饲料利用率的应用研究是非常必要的,不仅改善饲料利用率、提高动物生产性能,还为饲料资源的开发与利用乃至为畜牧业发展提供有效途径。而饲用酶制剂以其绿色、环保、安全等特点成为了该研究领域的热点。通常采用体外和半体内法评定酶制剂处理对粗饲料体外发酵和瘤胃降解特性的影响,并采用体内法评价酶制剂在反刍动物营养中的应用效果。研究表明,外源酶制剂的应用能够有效提高饲料消化率、奶牛产量、肉牛增重和肉羊增重,但其效果不一致,其效果受很多因素的影响,包括酶种类、酶活性、饲粮组成、添加水平、添加方式、动物种类及生长性能等。另外,由于人们对所用酶产品的生化特性掌握不足,导致了对其作用机理、优化条件及影响其作用效果因子的了解不够充分。如酶活性作为酶制剂最主要的生化特性,在使用前往往被忽略检测,并且目前国内外对酶活性的检测及质量评定还没有统一的标准。然而研究结果间直接进行比较也是不科学不合理的。本研究主要从饲用酶制剂的发展历程,反刍动物营养中纤维降解酶的作用机理、应用效果和影响其作用效果的因素以及存在问题等方面进行了综述,旨在为饲用酶制剂在反刍动物营养中的应用提供系统的科学知识。  相似文献   

8.
单宁是一类广泛存在于植物中的多酚化合物,因其涩味降低反刍动物采食量,故通常被归类为饲料中的抗营养因子。近年来,研究发现单宁可与蛋白质结合,抑制蛋白质被瘤胃过度降解,增加了蛋白质在后肠道的消化吸收,提高了反刍动物对氮元素(N)的利用率。此外,研究表明单宁在调控瘤胃发酵和抑制甲烷排放方面表现出积极作用。本文主要综述了单宁对反刍动物生产性能、瘤胃发酵和微生物区系的影响,旨在为其应用于反刍动物健康养殖提供合理的理论参考依据。  相似文献   

9.
反刍动物能够将人类不能利用的粗饲料转化为优质蛋白质——肉和奶,这对农业以及人类社会有着重要意义。但是这种转化效率与植物细胞壁的消化率有重要关系,目前植物性原料消化率较低,影响了转化效率。在反刍动物饲粮中补充外源酶制剂具有提高植物纤维消化的潜力,从而提高饲粮的利用效率。本文总结了外源酶制剂应用现状、作用模式以及发展方向,认为目前外源酶制剂在反刍动物应用上有积极的结果,也存在效果不明显的报道,这可能与酶谱、添加水平、添加方式、底物类型以及宿主的生产水平等方面有关。同时阐述了外源酶制剂是在饲喂前、瘤胃中、瘤胃后的不同环境中起到作用,但详细机制还需要继续深入探究。综上所述,尽管酶制剂应用还存在一些问题,以提高饲料消化率为目标的酶制剂仍将会是反刍动物添加剂发展的一个重要方向。  相似文献   

10.
Seaweeds are macroalgae, which can be of many different morphologies, sizes, colors, and chemical profiles. They include brown, red, and green seaweeds. Brown seaweeds have been more investigated and exploited in comparison to other seaweed types for their use in animal feeding studies due to their large sizes and ease of harvesting. Recent in vitro and in vivo studies suggest that plant secondary compound-containing seaweeds (e.g., halogenated compounds, phlorotannins, etc.) have the potential to mitigate enteric methane (CH4) emissions from ruminants when added to the diets of beef and dairy cattle. Red seaweeds including Asparagopsis spp. are rich in crude protein and halogenated compounds compared to brown and green seaweeds. When halogenated-containing red seaweeds are used as the active ingredient in ruminant diets, bromoform concentration can be used as an indicator of anti-methanogenic properties. Phlorotannin-containing brown seaweed has also the potential to decrease CH4 production. However, numerous studies examined the possible anti-methanogenic effects of marine seaweeds with inconsistent results. This work reviews existing data associated with seaweeds and in vitro and in vivo rumen fermentation, animal performance, and enteric CH4 emissions in ruminants. Increased understanding of the seaweed supplementation related to rumen fermentation and its effect on animal performance and CH4 emissions in ruminants may lead to novel strategies aimed at reducing greenhouse gas emissions while improving animal productivity.  相似文献   

11.
畜牧业集约化养殖越来越普遍。为提高反刍动物生产性能,饲喂大量能量饲料,进而引发亚急性瘤胃酸中毒(SARA),导致动物采食量下降、畜产品产出降低以及动物发生炎症反应。近年研究表明,SARA会改变瘤胃生理状态,而瘤胃健康对反刍动物饲养至关重要。本文综述了反刍动物SARA状态下瘤胃生理生化过程变化,结合瘤胃发酵模式变化和瘤胃微生物的改变,重点阐述了SARA引起的瘤胃上皮细胞形态结构变化、屏障功能改变、瘤胃上皮细胞中物质转运及相关载体表达及其引发的瘤胃上皮细胞炎症通路,为更好指导反刍动物饲养及为瘤胃营养生理生化研究提供参考。  相似文献   

12.
抗生素的违规使用威胁着畜牧业的健康发展,寻找可靠的抗生素替代物以减少抗生素的使用已成为当务之急。作者总结了反刍动物饲料中使用的抗生素种类,综述了益生菌、植物提取物、酶制剂、有机酸、抗菌肽、功能性寡糖等主要的反刍动物饲用抗生素替代物的作用机理,重点阐述了反刍动物饲用抗生素替代物对反刍动物瘤胃发酵、微生物区系、免疫机能及生产性能影响的研究进展,并对反刍动物饲用抗生素替代物在实际生产中的应用进行了展望,以期为后续对反刍动物饲用抗生素替代物的研究和应用提供参考。  相似文献   

13.
In the last five decades, attempts have been made to improve rumen fermentation and host animal nutrition through modulation of rumen microbiota. The goals have been decreasing methane production, partially inhibiting protein degradation to avoid excess release of ammonia, and activation of fiber digestion. The main approach has been the use of dietary supplements. Since growth-promoting antibiotics were banned in European countries in2006, safer alternatives including plant-derived materials have been explored. Plant oils, their component fatty acids,plant secondary metabolites and other compounds have been studied, and many originate or are abundantly available in Asia as agricultural byproducts. In this review, the potency of selected byproducts in inhibition of methane production and protein degradation, and in stimulation of fiber degradation was described in relation to their modes of action. In particular, cashew and ginkgo byproducts containing alkylphenols to mitigate methane emission and bean husks as a source of functional fiber to boost the number of fiber-degrading bacteria were highlighted. Other byproducts influencing rumen microbiota and fermentation profile were also described. Future application of these feed and additive candidates is very dependent on a sufficient, cost-effective supply and optimal usage in feeding practice.  相似文献   

14.
棉粕是一种仅次于豆粕的优质植物性蛋白原料,蛋白质含量高,氨基酸种类丰富,但由于含有多种抗营养因子而限制了其在饲料中的应用。利用微生物发酵法处理棉粕可以有效降低其抗营养因子含量,还能提高发酵底物中小分子肽、消化酶、有机酸、益生菌等的含量,从而提高其营养价值。发酵棉粕在动物生产中有较为广泛的应用,在生长育肥猪日粮中使用5%~10%的发酵棉粕替代豆粕,对猪的采食量、日增重和料肉比等指标均没有显著影响,且可降低饲料成本;在鸡日粮中添加5%~15%的发酵棉粕可以提高鸡群免疫力,降低发病率,从而节约用药成本,并可改善鸡肉、鸡蛋的品质;发酵棉粕还可作为反刍动物精料补充料中的蛋白质原料,其所含的营养物质可通过促进瘤胃微生物的生长繁殖从而增加反刍动物对粗饲料的利用率;在水产饲料中用发酵棉粕代替鱼粉和豆粕,不仅可以降低饲料成本及饵料系数,还可以改善水质,提高水产动物体内消化酶含量,从而提高营养物质的消化吸收率。作者综述了发酵棉粕的营养价值,并总结了其在动物生产中的应用研究进展。  相似文献   

15.
This study was designed to determine effect of various plant protein sources in high-quality feed block (HQFB) on feed intake, rumen fermentation, and microbial population in swamp buffalo. Four rumen-fistulated swamp buffaloes (Bubalus bubalis) were randomly assigned according to a 4 × 4 Latin square design. Four kinds of plant protein sources (coarse rice bran (CRB), cassava hay (CH), Phaseolus calcaratus hay, and mulberry hay (MH)) were mixed in the HQFB. HQFBs were allowed to be licked at free choice, and urea-lime-treated rice straw (ULRS) were fed ad libitum. It was found that bacterial population and fungal zoospores in CH-fed group tended to be higher than those in other groups. Moreover, protozoal population in CH, P. calcaratus hay, and MH were lower than those in CRB supplemented group (P < 0.05). Cellulolytic bacterial population was highest in CH-fed group while proteolytic bacteria population was highest in P. calcaratus hay-fed group (P < 0.05). CH-fed group had higher ULRS intake than those in other groups (P < 0.05). Nutrient digestibility of CP, NDF, and ADF in CH-fed group was significantly higher than those in other groups (P < 0.05). Total VFA was highest in CH-fed group (P < 0.05). N absorption was highest in CH-fed group (P < 0.05). Based on this study, it could be concluded that cassava hay, P. calcaratus hay, and mulberry hay are potential to be used as protein sources in the HQFBs especially cassava hay.  相似文献   

16.
随着反刍动物规模化养殖的发展,高精料饲喂是促进反刍动物快速生长的常用策略,但这通常会导致动物瘤胃代谢紊乱等问题。瘤胃调节剂作为一类高效、安全、价格低廉的营养代谢调控剂在反刍动物饲养中得到广泛应用,但其使用的效果和作用机制目前还存在着不同的观点。本文综述了瘤胃调节剂在反刍动物中应用的国内外研究进展,以期为今后开展瘤胃代谢调控研究提供参考。  相似文献   

17.
High-quality protein roughage is an important feed for productive ruminants. This study examined the effects of strategic feeding of lactating cows with cassava (Manihot esculenta) top silage (CTS) on rumen fermentation, feed intake, milk yield, and quality. Four early lactating crossbred dairy cows (75% Holstein-Friesian and 25% Thai) with body weight (BW) 410?±?30 kg and milk yield 12?±?2 kg/day were randomly allotted in a 4?×?4 Latin square design to four different supplementation levels of CTS namely, 0, 0.75, 1.50, and 2.25 kg/day of dry matter (DM). Strategic supplementation of CTS significantly affected ruminal fermentation end-products, especially increased propionate production, decreased protozoal population and suppressed methane production (P?<?0.05). Increasing the CTS supplementation level substantially enhanced milk yield and the 3.5% FCM from 12.7 to 14.0 kg/day and from 14.6 to 17.2 kg/day (P?<?0.05) for non-supplemented group and for the 2.25 kg/day supplemented group, respectively. We conclude that high-quality protein roughage significantly enhances rumen fermentation end-products, milk yield, and quality in dairy cows.  相似文献   

18.
Recently obtained information on applications of the unique degradation ratio system (DRS) as an alternative method for feed evaluation and diet formulation is reviewed, in relation to optimum rumen fermentation and nutrient utilization and availability. The DRS ratio values show the balance between potentially microbial protein synthesis from rumen degradable crude protein and that potentially from the energy extracted during anaerobic fermentation in the rumen. In modeling feed evaluation and diet formulation, the degradation ratios can be used in assisting to detect effects of feed processing and optimize the composition of ruminant diets. Unfortunately, few researchers provide such crucial ratio data when they studied rumen degradation characteristics of a feed or diet mainly due to lack of knowledge of the DRS system. The emphasis of this article is on: (i) systematic introduction of the DRS system; and (ii) prediction the optimal rumen fermentation using the DRS system. The information described in this article may give better insight into the principal, computation and applications of the DRS system for feed and diet evaluation. A focus of the article is on evaluation of the DRS system as an alternative new approach to establishment of a feed evaluation system that more accurately accounts for feed digestive processes in the ruminant on a quantitative basis.  相似文献   

19.
反刍动物通过嗳气方式经口排出的甲烷,是瘤胃发酵能量损失的主要原因,也是导致环境温室效应的重要因素。因此,如何减少反刍动物瘤胃内甲烷的生成量对提高饲料能量利用率和改善环境具有重要意义。文章就甲烷的产生机理和调控减排技术研究进展作一阐述。  相似文献   

20.
反刍动物甲烷排放量营养调控技术的研究进展   总被引:1,自引:0,他引:1  
本文通过研究甲烷产生的机理,阐述降低反刍动物瘤胃内甲烷的产量的调控方法,旨在为缓解温室效应、减少反刍动物瘤胃发酵的能量损失,找到一项重要的反刍动物绿色营养调控技术提供理论参考依据.  相似文献   

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