稻秆和麦秸纤维成分瘤胃降解特性的比较研究

本试验用３头安装有永久性瘤胃瘘管的阉马头山羊，依瘤胃尼龙袋法分别测定了稻秆和麦秸全植株不同形态部分及不同节段的干物质、细胞内容物，中性洗涤纤维、酸性洗涤纤维、木质素、纤维素和半纤维素的瘤胃４８小时降解率，比较分析表明：麦秸和稻秆不同形态部分的差异是其营养价值差异性的真正来源；纤维成分瘤胃降解率相互间差异极显著（Ｐ＜０．０１），农作物品种的影响也极其明显。     

体外产气法和尼龙袋法评定苎麻的饲用价值

本试验通过体外产气法和尼龙袋法对苎麻叶片、苎麻全株以及苎麻去纤维全株的饲用价值进行评定。采用体外产气法测定苎麻叶片、苎麻全株以及苎麻去纤维全株的72 h动态产气量,并求得产气参数;用上述3种原料进行尼龙袋试验,测定干物质(DM)、粗蛋白质(CP)、中性洗涤纤维(NDF)及酸性洗涤纤维(ADF)的降解率,求得降解参数。结果表明:1)产气试验中,苎麻全株72 h产气量及理论最大产气量均最高,显著高于最低的苎麻去纤维全株(P0.05),苎麻叶片居中,苎麻叶片与其他二者差异不显著(P0.05)。2)尼龙袋试验中,DM、CP、NDF及ADF的72 h降解率均为苎麻叶片苎麻全株苎麻去纤维全株;DM、NDF、ADF有效降解率也呈现相同的变化规律;然而CP有效降解率则表现为苎麻全株苎麻叶片苎麻去纤维全株。从体外产气量和有效降解率来看,苎麻叶片和苎麻全株的饲用价值要优于苎麻去纤维全株。     

奶牛主要植物性蛋白质饲料蛋白质和纤维物质瘤胃降解率的研究

选用3头安装永久性瘤胃瘘管的健康荷斯坦产奶牛为试验动物,选取8种北方地区奶牛常用蛋白质饲料原料为试验样品,每个样品设3个重复,用尼龙袋法分别测定各个样品的粗蛋白质(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)在瘤胃内的动态降解率和有效降解率。结果表明:(1)所选8种蛋白质饲料原料中葵花粕的粗蛋白质(CP)有效降解率均高于其他粗饲料,达到61.17%以上,酒精粕的粗蛋白质(CP)有效降解率最低,仅为19.03%。(2)在饲喂基础上,玉米蛋白粉所含的瘤胃降解蛋白质(RDP)的比例最高,达到30.99%以上,而酒精粕所含的比例最低,仅为5.52%。(3)豆粕所含的中性洗涤纤维(NDF)的有效降解率最高,达到50.74%以上,而菜籽粕的最低,仅为11.06%。(4)玉米蛋白粉所含的酸性洗涤纤维(ADF)的有效降解率最高,达到59.23%以上,而酒精粕的最低,仅为11.27%。     

发酵菠萝渣养分瘤胃降解率的研究

利用施氏假单胞菌、枯草芽孢杆菌和乳酸杆菌对新鲜菠萝渣进行微生物发酵,用5只体格健壮、装有永久性瘤胃瘘管的山羊,采用尼龙袋法对发酵菠萝渣养分在瘤胃0、6、12、24、48、72h的降解率进行了研究。试验结果表明:发酵菠萝渣中粗蛋白质(CP)的动态降解率为52.28%,快速降解部分为9.62%;干物质(DM)、中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)在48h的降解率分别为80.67%、72.47%和61.44%,在72h的降解率分别为85.51%、78.96%和74.52%。     

不同紫花苜蓿品种瘤胃降解特性比较

为研究不同紫花苜蓿（Medicago sativa L.）品种在牛瘤胃中的降解规律,本试验以10个紫花苜蓿品种为材料,以3头装有永久性瘘管的晋南牛作为试验动物,采用尼龙袋法测定不同紫花苜蓿品种干物质（DM）、粗蛋白质（CP）、中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）的瘤胃降解率和降解参数。结果表明：不同紫花苜蓿品种DM,CP,NDF和ADF的降解率随着其在瘤胃内培养时间的延长,均呈升高趋势,但不同品种在同一培养时间段内的降解率存在显著差异;不同紫花苜蓿品种的有效降解率（ED）的差异较大,‘WL-319HQ DM’的ED最高,显著高于‘中苜一号’和‘首领’（P<0.01）;‘金皇后’CP的ED显著高于除‘赛迪’之外的其他品种;‘WL-168HQ’、‘中苜一号’NDF的ED显著高于除‘首领’之外的其他品种;‘三得利’、‘皇后’ADF的ED显著高于其他品种（P<0.05）。由此可见,不同紫花苜蓿品种在瘤胃内的降解特性不同。     

Rumen Degradation Characteristics of Six Types of Common Roughage in Khorchin Beef Cattle in Tongliao City

[Objective] The paper was to study the degradation characteristics of different types of roughage in Khorchin beef cattle. [Method] The nylon bag method was used to determine the rumen degradability of six types of roughage: dry matter(DM), crude protein(CP), neutral detergent fiber(NDF) and acid detergent fiber(ADF). [Result] Among the six types of roughage, alfalfa hay had the highest effective degradability of DM and CP in rumen; followed by alfalfa block, corn silage, leymus chinensis and corn stover, and the effective degradability of rice straw was lowest. In terms of effective degradability of NDF and ADF, alfalfa hay was the most effective, while leymus chinensis was the least effective. [Conclusion]Considering degradation characteristics of six types of roughage in Khorchin beef cattle, alfalfa hay possesses the highest nutritional value, while rice straw has the lowest value.     

Energy Supply to Livestock from Tropical Rangeland during the Dry Season

Nine key forage species (grasses and legumes), together with two types of crop residues, usually fed by farmers to their livestock, were collected from a rainfed area in western Sudan during the dry season (May–April). The grasses investigated were Leptadena pyrotechnia, Cenchrus setigrus, Arista pallida, Eragrotis tremula, Schoenefeldia gracilis, Chloris vergata and Cenchrus biflorus. The crop residues investigated were the grasses, sorghum straw (Sorghum bichlor) and millet straw (Pennisetum typhodium) and the legumes Stylosanthes flavicans and Cajanus cajana. Estimates of organic matter (OM) degradability were done using the nylon bag technique, which was fitted into the model Y = a + b (1 – e^–ct), in which the asymptote (a + b) represented the total potential degradability. Organic cell wall constituents and hence both metabolizable energy and total digestible energy or nutrients (TDN) were determined. S. flavicans showed the best organic matter degradability, and sorghum straw was better degraded than millet straw. The rest of the grasses showed poor OM degradability. Acid detergent insoluble nitrogen was inversely related to TDN, the latter falling within a narrow range for the different forages. Fermentable metabolizable energy differed only slightly, while the legume S. flavicans had the highest effective rumen digestible protein. Undegraded proteins were high for the straws and the grasses L. pyrotechnia and C. setigerus. Metabolizable protein and microbial protein were highest in the sorghum straw, C. setigerus and S. flavicans.     

Degradation characteristics and tannin bioassay of some browse forage from Kenya harvested during the dry season

The potential nutritional value of six species of browse forage from Kenya harvested during the dry season were evaluated by chemical composition, in sacco dry matter (DM) degradation and in vitro gas production technique. The effect of tannins on the rumen fermentation of the forage was evaluated using polyethylene glycol (PEG) in an in vitro study. The chemical composition of the species of browse forage differed significantly (P < 0.05). The content of organic matter ranged from 846.7 to 946.5 g/kg DM. The forage had a high crude protein content (155.5–280.9 g/kg DM) and variable content of neutral detergent fiber (NDF, 236.2–682.8 g/kg DM). The content of total extractable tannins was generally low (0.6–38.5 g/kg DM). At 24 h of incubation, the in sacco DM disappearance ranged from 31.2% to 84.2%. The effective DM degradability also ranged from 29.7 to 73.5%. The gas production after 96 h incubation ranged from 17.5 to 44.2 mL/200 mg DM. Use of PEG indicated that tannins had an inhibitory effect on rumen microbial fermentation and this is dependant upon the amount and activity of the tannins present. The estimated in vitro organic matter digestibility and metabolizable energy also increased numerically with the PEG addition. The result of this study indicates that such species of browse forage have the potential to be used as feed supplements for ruminants, especially during the dry season.     

Influences of grassland degradation on forage availability by sheep in the Inner Mongolian steppes of China

In China and throughout the world, evaluation of the nutrient values of forages has always lagged behind research regarding the nutrient requirements of animals. In this study, the effective degradability and availability of forages were evaluated on undegraded and degraded grassland using a technique where nylon bags were incubated in sheep rumen. We found that the concentrations of organic matter (OM), neutral detergent fiber (NDF), non‐fiber carbohydrates (NFC) and carbohydrates (CHO) of forage were higher (P < 0.05) and the crude protein (CP) concentration was lower (P < 0.05) in the degraded grassland than in the undegraded grassland. The effective degradability (ED) of NFC (ED_NFC) was higher (P < 0.05) and ED_CHO and ED_NDF were lower in the undegraded grassland than in the degraded grassland. The ED_OM and ED_CP were not affected by the type of grassland, which may explain why ED is an inadequate parameter for the evaluation of forage availability. According to an analysis of the ratio of effectively degraded N to OM and NFC, plants of the undegraded grassland can provide more digestive nutrients to meet the requirements of grazing animals compared to plants of the degraded grassland. Results suggested that it is inadequate to consider only chemical composition and effective degradability when evaluating forage availability with grassland degradation. The ratio of effectively degraded N to OM and NFC was an appropriate indicator.     

奶牛主要植物性蛋白质饲料蛋白质和纤维物质瘤胃降解率的研究

选用3头安装永久性瘤胃瘘管的健康荷斯坦泌乳奶牛为试验动物,选取8种北方地区奶牛常用蛋白质饲料原料为试验样品,每个样品设3个重复,用尼龙袋法分别测定各个样品的粗蛋白质（CP）、中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）在瘤胃内的动态降解率和有效降解率。结果表明,①所选8种蛋白质饲料原料中葵花粕的粗蛋白质（CP）有效降...     

裹包全混合日粮瘤胃降解特性的研究

试验选用2头安装有永久性瘤胃瘘管的荷斯坦奶牛作为试验动物,采用尼龙袋法研究了裹包贮存、精粗比和水分含量对全混合日粮(TMR)营养成分瘤胃降解特性的影响。结果表明:裹包贮存可显著提高TMR饲料干物质(DM)、粗蛋白(CP)和中性洗涤纤维(NDF)的瘤胃消失率和有效降解率(P0.05)。DM和CP的瘤胃消失率及有效降解率随TMR饲料精料水平的提高显著增加(P0.05)。水分含量60%组TMR饲料中CP的有效降解率显著高于40%和50%组(P0.05),40%和50%组间差异不显著(P0.05)。因此,裹包贮存可提高TMR饲料中营养物质瘤胃消失率和有效降解率(P0.05),营养物质的瘤胃消失率和有效降解率随TMR饲料精粗比的增加而增加,水分含量对裹包TMR中不同营养物质的消失率和有效降解率有不同影响。     

粉碎细度与滤袋对饲草NDF与ADF含量的影响

以取自山东省内草捆、草粉、草颗粒和青贮饲料4大类饲草产品为材料,通过滤袋法测定样品流失重量比率、中性洗涤纤维（NDF）和酸性洗涤纤维（ADF）含量,研究了不同粉碎细度（9目、18目和40目）和不同孔径的聚酯布、尼龙布、无纺布滤袋处理对饲草中NDF和ADF含量的影响。结果显示,粉碎细度处理对F58滤袋内样品重量流失率影响差异不显著,变化范围为1.37%～1.86%;对NDF含量影响显著,40目处理显著低于9目处理（P<0.05）,与18目处理差异不显著。ADF含量在各粉碎细度处理间变化不明显,10个样品中有6个样品各处理间差异不显著。不同滤袋试验结果表明,CAU滤袋测定样品NDF和ADF含量与F58滤袋差异不显著,而其它滤袋处理的测定值均与F58滤袋差异显著（P<0.05）,聚酯布和尼龙布滤袋在ADF测定中出现封口内缘断裂现象。     

Effect of Adding Different Mannan Oligosaccharide to Diets with Different Concentrate to Forage Ratios on Rumen Degradability of Fiber in Sheep

To investigate the effect of adding mannan oligosaccharide to diets with different concentrate to forage ratios on the degradability of neutral detergent fiber (NDF) and acid detergent fiber(ADF) in rumen of sheep by nylon bags technique,6 wethers (White Suffolk♂×Small-tailed Han sheep♀) installed permanent rumen fistula were used for offering rumen fluid.The 4×6 two-factor experimental design was chosen and the two factors were the ratio of concentrate to forage (A1(20:80),A2(30:70),A3(40:60),A4(50:50)) and the dose of mannan oligosaccharide (B1 (0),B2 (0.4%),B3 (0.8%),B4 (1.2%),B5 (1.6%),B6 (2.0%)).The results showed that the rumen degradability of NDF and ADF in different times,degradation parameters and effective degradability were influenced by the factor A significantly (P< 0.05).The rumen degradability of NDF and ADF in each time of group A1 were higher than group A3 and A4 (P< 0.05).Expect for 24 h,the rumen degradability of ADF were influenced significantly by the factor B,and the rumen degradability of ADF in group B5 was higher than group B1 and B2 (P< 0.05).The rumen effective degradability of NDF in group A3 was significantly higher than groups A1 and A2 (P< 0.05), and a little higher than group A4 (P >0.05),which showed that the rumen effective degradability of NDF and ADF were higher when the ratio of concentrate to forage was 40:60.     

不同精粗比日粮添加甘露寡糖对绵羊瘤胃纤维降解率的影响

选取6只安装永久瘤胃瘘管羯羊(白萨福克♂×小尾寒羊♀)为瘤胃液供试动物,采用4×6二因子析因试验设计,共设2个因子,分别为不同精粗比日粮(A1(20:80)、A2(30:70)、A3(40:60)、A4(50:50))和不同甘露寡糖添加量(B1 (0)、B2 (0.4%)、B3 (0.8%)、B4 (1.2%)、B5 (1.6%)、B6 (2.0%)),进行尼龙袋半体内试验,旨在研究不同精粗比日粮中添加甘露寡糖对绵羊瘤胃中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)降解率的影响。结果表明,A因子对日粮中不同时间点NDF、ADF瘤胃降解率、降解参数及有效降解率均产生了显著影响(P< 0.05),A1处理组的NDF和ADF各个时间点(除3 h外)的瘤胃降解率均显著高于A3和A4处理组(P< 0.05);B因子对3、6、9、12、48 h的瘤胃ADF降解率均产生了显著影响(P< 0.05),其中B5处理组显著高于B1、B2处理组(P< 0.05);A3处理组的NDF有效降解率显著高于A1、A2处理组(P< 0.05),稍高于A4处理组(P >0.05)。综上所述,在精粗比为40:60时,NDF和ADF的瘤胃有效降解率处于较高水平。     

白羊草灌丛草地优势种牧草营养物质及瘤胃降解动态研究

对白羊草灌丛草地优势种牧草白羊草、达乌里胡枝子、尖叶铁扫帚、铁杆蒿和隐子草的营养动态进行了研究,结果表明:随着生育期的延续,牧草粗蛋白质和粗灰分含量逐渐降低,而酸性洗涤纤维和中性洗涤纤维则呈相反的趋势;豆科牧草与铁杆蒿的粗蛋白质含量以现蕾期为转折点,禾本科牧草则以开花初期粗蛋白质含量较高.同时,对白羊草和达乌里胡枝子在绵羊瘤胃内的降解动态的研究表明:粗蛋白质含量高的其粗蛋白质降解率高,白羊草在开花期的粗蛋白质降解率高于抽穗期,但稍低于拔节期,达乌里胡枝子在现蕾期的粗蛋白质降解率高于分枝期;瘤胃降解率在前24h迅速上升,之后则较平缓;8月份白羊草处于开花期,为地上生物量的高峰期,对放牧极为有利.     

西藏山南地区6种野生牧草营养价值评定

选用6只装有瘘管的西藏澎波半细毛羊,用尼龙袋法对采于西藏山南地区的6种野生禾本科牧草的营养成分含量及其在绵羊瘤胃内的降解特性进行了测定,分析评价其营养利用价值。结果表明:6种牧草的干物质(DM)、粗蛋白质(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的瘤胃降解消失率和降解特征存在很大差异;随着样品在瘤胃内停留时间的延长,降解消失率也随之提高,在3-48 h时,增加的幅度较快,48h后,增加的速度放缓;到72 h,狗尾草(Setaria viridis (L.) Beauv.)的降解消失率最大,其DM、CP和NDF的降解消失率均超过60%;蛋白质较高、纤维含量较低的狗尾草和白草(Pennisetum centrasiaticum Tzvel.),其DM、CP、NDF和ADF的快速降解部分、慢速降解部分及有效降解率均比其他4种牧草高;而白茅(Imperata cylindrical (L.) Beauv.)和沙生针茅(Stipaplareosa P.Smirn.)营养成分表现出比其他4种牧草差的降解特征。综合考虑6种牧草所含营养成分及其在绵羊体内的降解能力,狗尾草和白草利用价值较高,白茅和沙生针茅利用价值较低。     

Characterization of in situ nitrogen and fiber digestion and bacterial nitrogen contamination of hay crop forages preserved at different dry matter percentages

Alfalfa, red clover, orchardgrass and timothy were harvested in the vegetative stage, wilted and stored as hay, or ensiled in small batch silos (20 kg) at 60, 40 or 20% (direct cut) dry matter and were analyzed for compositional differences. A ruminally cannulated lactating cow, consuming 50% of her dry matter intake from hay crop silage, was used to measure in situ dry matter, N, neutral detergent fiber and acid detergent fiber disappearance. Diaminopimelic acid was used as a bacterial marker to correct for bacterial N contamination for in situ residual N. Fibrous components tended to become concentrated as percent dry matter at preservation decreased, presumably associated with leaching of water solubles during storage. For most forages, as dry matter percentage of preservation decreased, water soluble dry matter and N increased, with a concomitant increase of ruminally nondigested dry matter. Specific trends in coefficients of digestion associated with forage type or preservation dry matter percentage were not observed for dry matter, N, neutral detergent fiber or acid detergent fiber. Correction for contamination by bacterial N decreased lag time in digestion and altered rates of N digestion compared with noncorrected rates. Linear and quadratic bacterial N contamination profiles were observed with time of ruminal incubation. Rate of digestion of N was highly correlated with fibrous component concentration, and to a lesser extent to rate of neutral and acid detergent fiber digestion. Dry matter percentage at preservation had a variable effect on ruminal digestion rate of dry matter and N, which varied with forage type and had no effect on neutral detergent and acid detergent fiber digestion rates. Correction for bacterial N contamination should be considered when establishing N digestion rates for forage by the in situ technique.     

不同刈割期对饲用小黑麦草产量和营养品质的影响

为了筛选湖南地区饲用小黑麦（Triticale Wittmack）的最佳刈割时期，本试验研究了2个小黑麦品种（‘中饲1048’，‘冀饲2号’）和2个小黑麦新品系（‘中饲3297’，‘中饲1257’）在3个刈割期（拔节期，灌浆期，成熟期）的农艺性状、草产量和营养品质。结果表明：不同刈割期小黑麦的株高、分蘖数、绿叶数、鲜草和干草产量均存在显著差异，灌浆期的鲜草和干草产量（46.92和12.97 t·hm^-2）最高，拔节期的绿叶数（4.10片）最多，成熟期的株高（176.76 cm）最高，分蘖数（329.17万个·hm^-2）最多。不同刈割期小黑麦的粗蛋白、粗脂肪、粗灰分、中（酸）性洗涤纤维、酸性洗涤木质素和可溶性糖含量均存在显著差异，随着刈割期的推迟，粗蛋白、粗脂肪和粗灰分含量逐渐下降，中（酸）性洗涤纤维和酸性洗涤木质素含量逐渐增加，可溶性糖含量逐渐下降。综合分析表明，饲用小黑麦的最佳刈割时期为灌浆期，此时鲜（干）草产量最高，营养品质较高。     

利用尼龙袋法比较3个全株玉米品种青贮前后肉牛瘤胃降解特性

本试验旨在利用尼龙袋法比较不同品种全株玉米青贮前后瘤胃降解特性的差异.试验采用2×3双因素试验设计,选择玉米7367号、玉米7377号、玉米7387号3个全株玉米品种为研究对象,采用尼龙袋法比较3种全株玉米青贮前和青贮后的营养成分和瘤胃降解特性,旨在探讨适合河北省种植的全株玉米青贮品种.结果表明:1)青贮前玉米7377...     

In vitro degradation characteristics of Timothy and Red Clover at different harvest times

The nutritional value of red clover (Trifolium pratense L.) and timothy (Phleum pratense L.) were studied over two consecutive growing seasons (1995 and 1996) with an in vitro gas production technique and chemical analysis. The decline in degradability was more pronounced with increasing maturity in timothy than in red clover during spring growth, but similar during summer growth. Red clover contained more components soluble in neutral detergent solution (NDS) at all harvest occasions. The fractional degradation rate for the NDS fraction was lower in red clover compared to timothy. Red clover had slightly higher fractional degradation rate for the whole forage, but the total kinetic release of energy was similar for the two species at the same harvest time. The results indicate that timothy and red clover have different intrinsic characteristics limiting degradation. Effects of the treatments with NDS on the allocation of pectins could partially explain the differences in degradation characteristics.