青海省农牧交错区牦牛12种常用粗饲料营养参数的测定

本研究结合常规营养成分分析和体外发酵产气技术,主要测定了青海省农牧交错区的农作物秸秆(小麦秸秆、豌豆秸秆、蚕豆秸秆、油菜秸秆及马铃薯秸秆)、优质补饲饲草(青贮玉米秸、苜蓿青干草、燕麦青干草)和天然草地型(线叶嵩草、高山柳+黑褐苔草、金露梅—珠芽蓼及藏嵩草)冷季牧草等牦牛12种常用粗饲料的常规营养成分及体外发酵产气参数等营养评价指标,结果表明,5种农作物秸秆除豌豆秸秆和蚕豆秸秆的粗蛋白质含量分别为8.5%、9.75%,其余秸秆均低于8%,有机物质消化率在40%～65%,代谢能在4.0～9.0MJ/kg;4种天然草地型冷季牧草的粗蛋白质均低于8%,有机物质消化率在48%～70%,代谢能在6.0MJ/kg～10.0MJ/kg的范围内;3种优质补饲饲草苜蓿青干草、燕麦青干草和青贮玉米秸的粗蛋白质含量分别为11.36%、8.79%、5.25%,有机物质消化率在42%～70%,代谢能在5.0～11.0MJ/kg。     

应用体外产气与活体外消化法评定不同生育期禾本科牧草营养价值

试验旨在探讨华北农牧交错带羊草、大赖草、扁穗冰草、无芒雀麦、野黑麦和梭罗草6种主要禾本科牧草不同生育期营养价值变化规律。利用常规化学成分分析、活体外消化技术和体外发酵产气技术测定6种禾本科牧草盛花期和结实期的主要营养成分、活体外消化率和瘤胃微生物体外发酵产气量。结果表明:除无芒雀麦外,结实期禾本科牧草粗蛋白(CP)和中性洗涤可溶物(NDS)含量相比开花期显著下降(P<0.05);中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)含量随生育期的延长而增加(P<0.05);6种牧草的干物质活体外消化率(DMD)、NDF活体外消化率(NDFD)、ADF活体外消化率(ADFD)随生育期延长呈下降趋势;除羊草外,5种牧草的2个生育期的24 h和48 h产气量差异显著(P<0.05),6种禾本科牧草2个生育期的理论最大产气量差异显著(P<0.05);随生育期延长,产气速度呈下降趋势,延滞期呈上升趋势。与开花期相比,禾本科牧草结实期的营养显著下降。     

巍山县肉牛常用饲料营养价值评定

对巍山县19种肉牛常用精、粗饲料的营养价值进行综合评定,测定了常规营养成分、范氏纤维成分、体外消化率、瘤胃降解率及能量价值。结果表明:不同饲料之间的营养成分、体外消化率、瘤胃降解率和有效能含量存在较大差异,优质粗饲料较秸秆饲料高,优质牧草较野生牧草高,而肉牛浓缩料和肉牛精料补充料比玉米面和牧草提供较大比例的过瘤胃蛋白。     

青藏高原不同海拔高度对禾本科牧草体外消化率的影响

利用大板山北坡3200m-3800m的海拔梯度,分别在3200m、3400m、3600m和3800m处选取羊茅、一年生早熟禾和(艹洽)草用二级离体培养法测定其体外消化率。1999和2000年测定结果表明,随着海拔的升高,3种牧草的体外消化率呈增加趋势,海拔从3200m升到3800m,羊茅、早熟禾、(艹洽)草的体外消化率分别增加6.42、6.35、8.69和4.89、9.8和5.1个百分点。显著性分析结果表明,供试牧草的体外消化率与其生长的海拔高度之间的正相关关系差异显著(P<0.05)。     

秸秆饲料怎样调制更营养

农作物秸秆如果加工、调制得当,是草食家畜不可缺少的好饲料,既能节省饲料用粮,又可实现过腹还田培肥地力。目前,生产中常用物理、化学和生物学3类方法综合运用对农作物秸秆(包括饲用牧草)进行加工调制,可有效提高其适口性、营养价值和家畜的消化率,再配合饲喂其他全价     

西藏主要栽培牧草、作物秸秆营养价值评价

通过对西藏4种栽培牧草和6种作物秸秆的6种营养成分的测定,应用随意采食量、净能估测模型计算了栽培牧草和作物秸秆的分级指数,对其进行了综合评价。结果表明:品质较好的栽培牧草为隆孜紫花苜蓿Medicagosativa、黄花苜蓿M.falcata和江孜紫花苜蓿。作物秸秆品质较好的为土豆Solanumtu-berosum、玉米Zea mays和燕麦Avena sativa。同时运用灰色关联度分析法对其营养价值进行了综合评价,结果表明:栽培牧草营养价值高的为紫花苜蓿和隆孜黄花苜蓿;作物秸秆营养价值较高的有土豆和玉米。运用粗饲料分级指数和灰色关联度分析法对栽培牧草、作物秸秆营养价值的评定结果较为一致。     

新疆沙尔套山四季放牧草地主要牧草营养价值变化特征研究

以新疆昭苏县域内沙尔套山分布的12种主要牧草为研究对象,对其营养物质和瘤胃体外消化率特征进行分析,以期揭示各牧草营养物质和消化率的季节性变化规律。结果表明,各牧草的营养物质含量和消化率特征指标均存在明显的季节性变化规律。通过模糊相似优先比分析,综合营养物质(干物质、粗蛋白、中/酸性洗涤纤维、粗脂肪、粗灰分)和瘤胃体外消化率特征(有机物消化率、代谢能)的8项指标进行综合营养价值评价,主要结论为:1)研究区放牧草地12种主要牧草中针茅、芨芨草、紫花鸢尾综合营养价值最佳季节在春季营养生长期(6月),其余牧草均为夏季开花期(7月)。2)春季营养生长期(6月)和秋季果后营养期(9月),综合营养价值最好的均为鸭茅;夏季开花期(7月),综合价值最好的牧草为西伯利亚羽衣草;秋季结实期(8月),综合营养价值最好的牧草为红花车轴草;冬季停止生长(10月)和枯草期(11月),综合营养价值最好的分别为针茅和紫花鸢尾。     

体外法评定南方4种经济作物副产品及3种暖季型牧草的营养价值研究

旨在评价南方4种经济作物副产品及3种暖季型牧草的营养价值,开发新的饲料资源。试验采用单因素设计,通过体外产气法对14种样品进行评定,主要测定096 h的产气量,24 h发酵液的挥发性脂肪酸产量、氨态氮、微生物蛋白浓度、pH值以及体外干物质消化率。结果表明:木薯叶的粗蛋白和粗脂肪含量显著高于其他经济作物副产品及牧草(P0.05);产气量方面从大到小依次,经济作物副产品是柚子皮木薯淀粉渣木薯叶薏米秸秆,而牧草则是象草(印尼引进)皇竹草高丹草;柚子皮和木薯淀粉渣的理论产气量显著高于其他经济作物副产品及牧草;柚子皮的乙酸、丙酸、异戊酸、戊酸及总挥发酸显著大于其他经济作物副产品及牧草(P0.05);氨态氮含量最高的是象草(印尼引进),且与其他经济作物副产品及牧草相比差异显著(P0.05);pH值和微生物蛋白无显著差异(P0.05)。本试验选用的南方经济作物副产品及牧草的粗蛋白与粗脂肪含量适宜,微生物活性高,易消化,能够提供反刍动物所需要的能量,适合作为反刍动物的粗饲料来源。且经济作物副产品中柚子皮的营养价值最高,其次是木薯淀粉渣、木薯叶和薏米秸秆;而牧草中依次为象草(印尼引进)、皇竹草、高丹草。     

新疆沙尔套山四季放牧草地主要牧草营养价值变化特征研究

以新疆昭苏县域内沙尔套山分布的12种主要牧草为研究对象,对其营养物质和瘤胃体外消化率特征进行分析,以期揭示各牧草营养物质和消化率的季节性变化规律。结果表明,各牧草的营养物质含量和消化率特征指标均存在明显的季节性变化规律。通过模糊相似优先比分析,综合营养物质(干物质、粗蛋白、中/酸性洗涤纤维、粗脂肪、粗灰分)和瘤胃体外消化率特征(有机物消化率、代谢能)的8项指标进行综合营养价值评价,主要结论为:1)研究区放牧草地12种主要牧草中针茅、芨芨草、紫花鸢尾综合营养价值最佳季节在春季营养生长期(6月),其余牧草均为夏季开花期(7月)。2)春季营养生长期(6月)和秋季果后营养期(9月),综合营养价值最好的均为鸭茅;夏季开花期(7月),综合价值最好的牧草为西伯利亚羽衣草;秋季结实期(8月),综合营养价值最好的牧草为红花车轴草;冬季停止生长(10月)和枯草期(11月),综合营养价值最好的分别为针茅和紫花鸢尾。     

膨化艾草秸秆对湖羊消化代谢的影响

试验旨在研究膨化艾草秸秆对湖羊消化代谢的影响。选用3月龄、体重（25.27±0.57）kg的健康湖羊72只,随机分为3组,每组6个重复,每个重复4只（公母各半）。对照组饲喂基础饲粮,艾草秸秆组用16%艾草秸秆替代基础饲粮中16%干花生秧饲粮、膨化艾草秸秆组用40%膨化艾草秸秆替代基础饲粮中16%干花生秧饲粮和24%膨化玉米粉。预试期15 d,正试期56 d,在第42天每组选取6只体重相近的公湖羊进行消化代谢试验,预试期7 d,正试期4 d。结果表明：艾草秸秆组和膨化艾草秸秆组平均日增重和干物质采食量高于对照组（P<0.05）;与艾草秸秆组相比,膨化艾草秸秆组脂肪表观消化率只提高了14.43%(P<0.05);与对照组相比,艾草秸秆组和膨化艾草秸秆组的有机物表观消化率分别下降了5.30%(P<0.05)、5.95%(P<0.05),酸性洗涤纤维表观消化率分别下降了16.75%(P>0.05)、19.51%(P<0.05),粗蛋白质的表观消化率分别提高了6.13%(P<0.05)、6.47%(P<0.05),3组干物质和中性洗涤纤维表观消化率...     

西藏牧草和作物秸秆热值研究

对西藏牧草和常见作物秸秆热值进行了研究。结果表明:69个牧草的干质量热值和去灰分热值分别为16.06～20.68 kJ/g和17.83～22.47 kJ/g;天然牧草热值水平低于栽培牧草。所有牧草去灰分热值均高于世界陆生植物平均值(17.79 kJ/g),其中95.65%的牧草属于中高热值牧草。各科牧草干质量热值和去灰分热值排列顺序不同,而灰分含量是造成该差异的主要原因;作为牲畜主要饲草种类的禾本科牧草平均去灰分热值高达20.46 kJ/g。几种常见作物秸秆热值含量较牧草低,平均去灰分热值含量为17.75 kJ/g,但也接近世界陆生植物的平均水平。作物秸秆的干质量热值和灰分含量呈极显著线性负相关。     

Estimation of feeding value of four tropical forage species at two stages of maturity

The feeding value of four tropical grasses was assessed through voluntary intake and digestibility studies using yearling Brahman x British steers (average BW = 256 +/- 34 kg). The digestibility of OM was estimated using total fecal collection (TFC), in vitro OM digestibility (IVOMD), and by estimating fecal production using insoluble acid detergent fiber (IADF) as an indigestible marker. The four grasses consisted of bahiagrass (Paspalum notatum), limpograss (Hemarthria altissima), bermudagrass (Cynodon dactylon), and stargrass (Cynodon spp.). Grass was harvested at two stages of maturity (approximately 4 and 10 wk). Forages were ground (5 to 10 cm) and offered to steers ad libitum. Forage treatments were assigned randomly to steers over eight 28-d periods and repeated over two consecutive years. Total forage offered and refused was determined during a 14-d sample collection period. For determination of fecal output, steers were placed into metabolism crates for 7 d. Composited samples of forage offered, forage refused, and feces of each steer at each period were analyzed for DM, OM, NDF, ADF, IADF, IVOMD, and CP. All digestibility results were calculated on an OM basis. There were year x grass x maturity interactions (P < 0.01) for all measures of forage quality, except CP. Increased maturity resulted in a 37.8% decrease (P < 0.001) in CP concentration when averaged across all forages. Four-week bermudagrass contained the greatest (P < 0.05) concentration of CP compared with all other grasses at both maturities, except 4-wk stargrass. Bahiagrass IVOMD did not differ among 4- and 10-wk maturities in both years; however, the IVOMD content of both stargrass and bermudagrass decreased (P < 0.05) when these forages matured from 4 to 10 wk. Apparent OM digestibility, determined by TFC, was greater (P < 0.05) than OM digestibility determined by IVOMD and IADF for all forages except bahiagrass, for which IADF did not differ from TFC. In Year 1, OM intake (OMI) of 10-wk limpograss was less (P < 0.05) than all other 4-wk forages. In Year 2, voluntary OMI of 10-wk limpograss was less (P < 0.05) than all grass x maturity combinations, except for 10-wk bermudagrass. These data suggest that important differences exist in changes in nutrient quality associated with increased maturity in tropical forages. Among the forages assessed in this study, bahiagrass seems to better retain nutrient quality when maturing from 4 to 10 wk.     

不同粗饲料分级指数混合粗饲料与不同比例精饲料混合日粮体外有机物消化率研究

本试验通过体外连续培养分析了高、低分级指数混合粗饲料日粮24h连续培养中不同时间点培养液中的有机物消化率的动态变化。试验结果表明,高分级指数混合粗饲料日粮不需提高精饲料的比例就有较高的有机物体外消化率(IVOMD),且提高精饲料水平未必能提高其IVOMD,而低分级指数混合粗饲料日粮只有提高精饲料水平才能达到高分级指数混合粗饲料日粮的效果。     

In vivo digestibility of six selected fodder species by goats in northern Ghana

Tropical Animal Health and Production - An in vivo digestibility trial was conducted to evaluate the digestibility of six forages. These were selected indigenous browse species and groundnut haulms...     

Comparison of in vitro and in situ methods in evaluation of forage digestibility in ruminants

The objective of this study was to compare the application of different in vitro and in situ methods in empirical and mechanistic predictions of in vivo OM digestibility (OMD) and their associations to near-infrared reflectance spectroscopy spectra for a variety of forages. Apparent in vivo OMD of silages made from alfalfa (n = 2), corn (n = 9), corn stover (n = 2), grass (n = 11), whole crops of wheat and barley (n = 8) and red clover (n = 7), and fresh alfalfa (n = 1), grass hays (n = 5), and wheat straws (n = 5) had previously been determined in sheep. Concentrations of indigestible NDF (iNDF) in all forage samples were determined by a 288-h ruminal in situ incubation. Gas production of isolated forage NDF was measured by in vitro incubations for 72 h. In vitro pepsin-cellulase OM solubility (OMS) of the forages was determined by a 2-step gravimetric digestion method. Samples were also subjected to a 2-step determination of in vitro OMD based on buffered rumen fluid and pepsin. Further, rumen fluid digestible OM was determined from a single 96-h incubation at 38°C. Digestibility of OM from the in situ and the in vitro incubations was calculated according to published empirical equations, which were either forage specific or general (1 equation for all forages) within method. Indigestible NDF was also used in a mechanistic model to predict OMD. Predictions of OMD were evaluated by residual analysis using the GLM procedure in SAS. In vitro OMS in a general prediction equation of OMD did not display a significant forage-type effect on the residuals (observed - predicted OMD; P = 0.10). Predictions of OMD within forage types were consistent between iNDF and the 2-step in vitro method based on rumen fluid. Root mean square error of OMD was least (0.032) when the prediction was based on a general forage equation of OMS. However, regenerating a simple regression for iNDF by omitting alfalfa and wheat straw reduced the root mean square error of OMD to 0.025. Indigestible NDF in a general forage equation predicted OMD without any bias (P ≥ 0.16), and root mean square error of prediction was smallest among all methods when alfalfa and wheat straw samples were excluded. Our study suggests that compared with the in vitro laboratory methods, iNDF used in forage-specific equations will improve overall predictions of forage in vivo OMD. The in vitro and in situ methods performed equally well in calibrations of iNDF or OMD by near-infrared reflectance spectroscopy.     

反刍动物常用粗饲料消化率预测模型的验证研究

研究通过对江西反刍动物常用粗饲料体外消化率(IVDMD)的实际测定,证明邓卫东等(2002)建立的以范氏纤维含量为预测因子的粗饲料IVDMD预测模型在江西区域有较高的准确性,能够应用于江西反刍动物粗饲料消化率的预测。该模型与张吉鹍等(2004b;2010)建立的粗饲料干物质采食量预测模型构成了完整的反刍动物粗饲料分级指数(GI)参数模型,这将大力推进江西反刍动物粗饲料品质的综合评定。     

体外产气法评价宁夏地区四种非常规粗饲料的营养价值

本研究通过体外产气法研究了甘草茎叶、野草、柠条叶和柠条四种非常规饲料体外发酵24 h的产气量、产气参数,并应用Menke和Steingass(1988)模型估测了四种饲料的有机物消化率和代谢能,其中有机物消化率最高的是甘草茎叶(69.28%)(P<0.05),野草次之(55.73%),柠条最低(22.31%)(P<0.05);四种饲料的代谢能比较,甘草茎叶最高,为10.45 MJ/kg DM(DM,干物质)(P<0.05),野草次之(6.66 MJ/kg DM),柠条最低(4.23 MJ/kg DM)(P<0.05)。通过与中国农业科学院(1984)测定的国产饲料代谢能值比较,并结合四种饲料的有机物消化率值,甘草茎叶、野草和柠条叶对于反刍动物均具有一定的饲喂价值,而柠条营养价值极低,不适宜作为反刍动物的粗饲料。     

Intake and Apparent Digestibility of Permanent Meadow Hay and Haylage in Ponies

The aim of this article was to study the conservation quality, chemical composition, gross energy, voluntary intake, and apparent digestibility of permanent meadow haylage and hay, fed to ponies at maintenance. The forages were from the same swath and harvested at early flowering stage. The apparent digestibility of the hay and haylage, which contained about 61% neutral detergent fiber and 38% acid detergent fiber, as fed, was determined by means of two in vivo digestibility trials, each performed on six ponies, weighing, on average, about 335 ± 80 kg and 334 ± 41 kg, respectively, over a 6-day feces collection period after a previous 14-day adaptation period. The voluntary intake was measured and the digestibility coefficients were calculated for dry matter, organic matter, gross energy, crude protein, neutral detergent fiber, and acid detergent fiber, using acid-insoluble ash as the internal marker. The haylages were evaluated for dry matter, pH, alcohols, lactic acid, and monocarboxylic acid. The conservation quality of the haylage was good and its chemical composition was similar to that of hay, except for the crude protein and gross energy contents, which were higher (P < .05) as compared with those of the hay. No differences were found between the hay and haylage with regard to the voluntary intake and digestibility coefficients.     

Chemical composition, in vitro digestibility and gas production of straws from different varieties and accessions of chickpea

Chemical composition, in vitro digestibility and gas production of straw from four different varieties of Kabuli chickpea (Cicer arietinum) were studied. Kinetics of fermentation of straws from 19 different accessions of chickpea was also evaluated using gas production technique. Significant difference (p < 0.05) was observed in the yield of straw [from 1041 to 1174 kg dry matter (DM)/ha] from different varieties. The proportion of seed/straw from different varieties varied from 0.61 to 0.93. Crude protein, neutral detergent fibre and acid detergent fibre content of straw ranged from 28.1 to 35.8, 598.6 to 645.4 and 459.2 to 473.4 g/kg DM respectively. Organic matter digestibility was different (p < 0.05) among varieties and varied from 471.4 to 535.5 g/kg DM. Potential gas production (A), the rate constants (c and d) and lag times of straws from different chickpea varieties were not different (p > 0.05). However, the rate constants (c and d) and lag times were different (p < 0.05) among accessions. Potential gas production (A) differed (p < 0.05) approximately twofold among different accessions. The results emphasized that in any evaluation of chickpea varieties or accessions, where straw of this legume seed is used as an animal feed, not only seed yield but also yield and quality of straw should be taken into consideration.