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饲料间组合效应是指来自不同饲料来源的营养物质、非营养物质及抗营养物质间互作的整体效应。反刍动物饲料间的组合效应表现得更为突出和普遍。该文着重论述了反刍动物饲料间组合效应的概念、衡量指标和类型,及其发生机制和调控技术,为牧场和养殖户配制安全高效的日粮提供参考。 相似文献
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反刍动物饲料间组合效应评估参数及评估方法 总被引：1，自引：0，他引：1
反刍动物饲料间存在组合效应已经成为共识,由于反刍动物消化机能和饲料结构的复杂性,尽管国内外许多研究者对饲料间的组合效应进行了大量研究,但是组合效应的评估方法和发生机制仍未形成系统的理论。1 组合效应的概念和衡量指标日粮成分之间的相互作用是1 9世纪末德国科学家Forbes首次观察到的,他发现日粮中的淀粉有碍于干草的消化。组合效应最明显的特点就是饲料混合后日粮的表观消化率不等于组成该日粮的各饲料消化率的加权之和。卢德勋(2 0 0 0 )作了明确的定义,日粮的组合效应实质上是指来自不同饲料源的营养性物质、非营养性物质以及… 相似文献
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从传统饲养体系的局限性到组合效应的概念、衡量指标类型、试验研究、发生机制、等方面综述了反刍动物日粮组合效应的研究方法与应用. 相似文献
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从传统饲养体系的局限性到组合效应的概念、衡量指标类型、试验研究、发生机制、等方面综述了反刍动物日粮组合效应的研究方法与应用。 相似文献
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试验选用1日龄健康五龙鹅雏,研究了饲粮中不同钙磷水平对0～4周龄五龙鹅生产性能、血浆钙磷含量和碱性磷酸酶(AKP)活性以及胫骨灰分及钙磷含量的影响。试验采用4×2二因子设计,饲粮钙水平设计为0.65%、0.75%、0.85%和0.95%,非植酸磷(NPP)水平设计为0.3%和0.4%。结果表明:①本次试验条件下,以五龙鹅最大体增重、采食量及最高饲料利用率为衡量指标,饲料中适宜的钙水平为0.65%,NPP为0.3%。钙磷间的交互作用对体增重、饲料消耗及料重比影响显著,以体增重与饲料消耗为衡量指标,最佳组合为0.65%Ca×0.3%NPP,Ca/NPP比为2.17,以料重比衡量最佳组合为0.65%Ca×0.4%NPP,Ca/NPP比为1.63。②以较高的血钙、血磷含量和较低的血浆AKP活性为衡量指标,饲粮中适宜的钙水平为0.65%,NPP为0.4%。钙磷间的交互作用对血浆钙磷水平及AKP活性影响极显著,以较高的血钙浓度为衡量指标较理想组合为0.65%Ca×0.4%NPP,以较高的血磷含量为衡量指标较理想组合为0.85%Ca×0.4%NPP,以较低的血浆AKP活性为衡量指标较理想组合为0.65%Ca×0.3%NPP。③以较高的胫骨灰分及钙磷含量为衡量指标,饲粮中适宜的钙水平为0.65%,NPP为0.4%。钙磷互作对胫骨灰分及钙磷含量影响极显著,以胫骨粗灰分及磷含量为衡量指标的较佳组合为0.75%Ca×0.4%NPP,Ca/NPP 相似文献
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反刍动物饲料间组合效应的评估参数包括不同碳水化合物比例产生的组合效应和饲料中的能氮平衡产生的组合效应两类。文章对饲料间的组合效应、评定方法及其评估参数等方面内容进行了综述,以供同行参考。 相似文献
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饲料间的组合效应及其在配方设计中的应用 总被引：7，自引：1，他引：6
就日粮中各饲料间的相互作用在消化道与组织代谢层次产生的正、负组合效应及其营养代谢机理进行了综述。指出现行日粮配方技术与饲料评定以各饲料原料间营养值的“可加性”为基础的不合理性,以及饲料间的组合效应没有引起足够重视的原因是现行的饲料常规分析方法不能反映饲料在动物体内的组合效应,从而有必要建立基于动物的饲料评定体系。研究就如何在日粮配方设计中通过日粮配合来调控饲料间的组合效应、避免饲料间的负组合效应、最大限度地发挥饲料间的正组合效应以提高饲料的营养价值及其在开发利用我国众多非粮饲料上的意义进行了讨论。 相似文献
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Three steers with simple rumen and abomasal cannulas were given ground and pelleted diets containing predominantly dried grass meal (DG) or rolled barley (RB). Diets were given at frequencies of two or eight feeds/d in a simple changeover design. Chromic oxide and polyethylene glycol were given as flow markers and flows (g/24 h) of organic matter (OM), nitrogenous and carbohydrate compounds were calculated. Ribonucleic acid and 35S were used as microbial markers and diaminopimelic acid (DAP) as a bacterial marker. Frequency of feeding had no significant effect on mean rumen pH, ammonia levels or liquid outflow rates with either diet. Rumen volume was decreased and abomasal digesta flow increased on Diet DG with more feeds but these parameters were unaffected with Diet RB. Increased feeding frequency with both feeds resulted in increased numbers of protozoa. There were no significant effects of feeding frequency of Diet DG on the abomasal flows of any of the nitrogenous constituents measured. However, there was a significant increase in microbial-N flow from 33 to 43 g/d with more frequent feeding of diet RB which was not reflected in bacterial-N flow as measured by DAP. The apparent digestion of OM in the rumen, expressed as g/g intake with diet DG was 0.41 and 0.31 for two feeds and eight feeds/d respectively. Corresponding values for diet RB were 0.56 and 0.63 respectively. The reduction in OM digestion with frequent feeding of diet DG was reflected in similarly reduced rumen digestibilities of all dietary carbohydrate components whereas the increase in OM digestion with diet RB was reflected only by the component sugars of the dietary fibre. The efficiencies of microbial protein synthesis (expressed as gMN/kg ADOM) increased from 36 to 46 when the feeding frequency of diet DG was increased from two to eight times/d. No significant effect of frequency of feeding was found for diet RB. Mouth to abomasum degradation of feed-N (expressed as g/g intake) of 0.64 was unaffected by the number of feeds of diet DG but was significantly increased from 0.55 to 0.82 when eight rather than two feeds/d of diet RB were given. 相似文献
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In vitro gas production measurements to evaluate interactions between untreated and chemically treated rice straws, grass hay, and mulberry leaves 总被引：15，自引：0，他引：15
In vitro gas production was measured to investigate associative effects of untreated and chemically treated rice straw (RS) and of RS and grass hay or mulberry leaves (ML). The RS was treated with NaOH, urea, or (NH4)HCO3. Cumulative gas production was recorded at 2, 4, 6, 8, 12, 16, 24, 36, 48, 60, 72, and 96 h of incubation, and the Gompertz function was used to describe the kinetics of gas production. Treatment with NaOH, urea, and NH4HCO3 increased (P < 0.05) gas production at 48 h by 55, 52, and 37% and the maximum rate of gas production of RS from 0.64 to 1.51, 1.27, and 1.13 mL/h, respectively. The inclusion of treated straws, hay, and ML in a mixture with RS at increasing proportions (25, 50, 75, 100%) elevated cumulative gas production and its rate. Maximum gas production was not different between the RS and its mixtures with the treated straws, but inclusion of hay into RS or NH4HCO3-treated RS increased the maximum gas production. Associative effects were defined as the difference between the observed gas production for the mixtures and the sum of the individual component feeds. The NaOH-treated RS, included at higher proportions, had positive associative effects at all times of incubation < 96 h; effects were negative or absent at 96 h. No effects were observed with mixtures of RS with urea-treated RS. The NH4HCO3-treated RS mixture tended to have negative associative effects at all three levels. Positive associative effects (P < 0.05) were observed for both RS and NH4HCO3-treated RS at almost all inclusion levels of hay or ML after 12 to 96 h of incubation. The response was more pronounced with ML than with hay. Associative effects generally declined with duration of incubation. We conclude that positive associative effects on in vitro gas production occurred more consistently when RS was incubated in mixtures with hay or ML than when incubated in mixtures with chemically treated RS. 相似文献
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文章旨在了解饲料与营养对肉牛生产性能、消化性能、瘤胃发酵以及甲烷(CH4)排放的影响。文章综述了2019年国外的相关文献报道,主要从精饲料、粗饲料及饲养营养综合评价3个方面进行综述。精饲料集中于各种蛋白质饲料和能量饲料的研究。粗饲料研究侧重于粗饲料品种和加工方式对不同生理阶段肉牛生产性能、消化性能和CH4产生的影响。饲料营养综合评价主要侧重于犊牛期研究,并对育肥期和放牧期肉牛的饲料营养进行评价,以根据肉牛的生理阶段特点,选择适宜的饲料原料,并合理搭配和调制日粮以改善瘤胃菌群结构,充分提高养分利用率。 相似文献
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Orskov ER 《Preventive veterinary medicine》1999,38(2-3):179-185
Principles of supplementation are discussed in respect of both, their positive and negative effects on roughage digestion and utilization by ruminants. It is pointed out that negative effects mainly occur when excessively processed concentrate is given in large quantities two times per day. This lowers rumen pH which in turn depresses cellulose digestion and intake of cellulosic feeds, leading to problems of acidosis and secondary ketosis due to off-feed conditions. To a large extent, such problems can be overcome by limited processing and feeding the concentrate mixed with the roughage. Supplements can also have positive effects by alleviating deficiencies such as nitrogen or by providing easily fermentable fiber to increase microbes for attachment to roughages. Supplements can increase microbial protein production and undegraded protein supply. It is emphasized that proper use and management of supplements can make the difference between profit and loss for small farmers. 相似文献
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常见饲料中抗营养因子及对动物的影响 总被引：5，自引：0，他引：5
抗营养因子（ＡＮＦ）指的是饲料是（或代谢产物中）所含有的一些对养分消化、吸收、代谢及动物健康和生产性能产生不良影响的物质。本文就常见饲料中的主要抗营养因子及其作用机理进行综述。 相似文献
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A. Wilfart Y. Jaguelin-Peyraud H. Simmins J. Noblet J. van Milgen L. Montagne 《Livestock Science》2007,109(1-3):179-181
Nutritional feed values are currently based on aggregate criteria such as the ileal or faecal digestibility. Digestibility is the result of two competing processes: digestion and passage. In order to develop mechanistic models of digestion to be used for feed evaluation, both processes have to be quantified. The aim of this study was to determine the hydrolysis kinetics of main constituents (organic matter, N and starch) in wheat, barley, wheat bran and soybean meal, using a three-step, enzymatic in vitro method mimicking digestion in the stomach, small and large intestine of pigs. Kinetics of hydrolysis (i.e. solubilisation of feed constituents) was modelled using an exponential segmented model estimating the extent and rate of digestion in each digestive segment. Digestion of organic matter of soybean meal occurred mainly in the stomach (67% vs. < 30% for other feeds) resulting from an efficient protein hydrolysis at this site. Organic matter of cereals was mainly digested in the small intestine (55%), as a result of starch digestion. Fractional digestion rates of organic matter were higher in the stomach than in the small intestine (20–35 vs. 2–15%/min). The potential digestibility of organic matter was nearly 87% for wheat and soybean meal, 78% for barley and 61% for wheat bran, which correspond to typical in vivo digestibility values. The results of the present study allow characterising different feeds with the objective to model the digestion process in pigs. 相似文献
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The inhibitory effects of iron- and sulfate-containing compounds on the in vitro digestion of a balanced forage diet by mixed populations of ruminal microorganisms were examined in batch cultures. Compounds containing ferrous and ferric cations consistently inhibited DM digestion by up to 36% when added Fe concentrations in cultures were between 100 and 1,000 mg/L. Increased sulfate concentrations of up to 200 mg/L or chloride concentrations of up to 635 mg/L were not associated with decreased DM digestion. Ammonium sulfate additions that provided 200 mg/L of added sulfur increased (P less than .05) digestibility by 10%. Sulfate-containing iron salts tended to be less inhibitory than chloride salts and were associated with increased gas production during digestion. Ferric chloride inhibited (P less than .05) microbial activities at lower concentrations than ferrous chloride. Data suggest that excessive iron supplementation or contamination of feeds with iron-containing pollutants may decrease microbial activities in the rumen. 相似文献