高能饲草饲料饲喂泌乳奶牛的试验效果分析

优质粗饲料是实现奶牛高产、减少奶牛营养代谢疾病、提高养殖经济效益的重要物质基础。使用一般的粗饲料，产奶净能低，对奶牛高产带来的障碍越来越明显。高能饲草饲料（简称高能饲草），是以秸秆为原料采用高新技术方法加工．大幅度提高饲草NDF的消化率，生产的新一代优质饲草饲料。高能饲草的产奶净能达2．13NND／千克，并且经过高温灭菌消毒处理，有效防止疫病的产生和传播，具有产奶净能高、瘤胃有机物发酵率高、饲用安全的特点。     

泌乳奶牛饲用高能饲草饲料试验

优质粗饲料是实现奶牛高产、减少奶牛营养代谢疾病、提高养牛业经济效益的重要物质基础.但作为许多地方主要粗饲料来源的玉米秸秆,在未经处理前,其营养价值较低,而据报道,将玉米秸秆加工成高能饲草饲料后,其产奶净能可达到2.13NND/kg;且经高温消毒处理,饲喂泌乳奶牛也很安全.为此,南京奶业集团原仙林奶牛场对盱眙金泰高能饲草饲料有限公司采用高新技术加工生产的高能饲草饲料进行饲喂试验,结果如下.     

稻草高能饲草饲料取代东北羊草的喂养试验

利用农作物秸秆生产高能饲草饲料新技术，采用消除植物纤维消化障碍的高科技方法，大幅度提高植物NDF的牛消化率。新产品稻草高能饲草饲料的产奶净能达1．43Mcal／kg。在泌乳中后期奶牛中，用3kg稻草高能饲草饲料取代3kg东北羊草，产品适口性好，可减缓牛只产奶量的下降速度。试验期试验组平均每头牛每日多产奶1．00kg，增收1．50元，经济效益显著。奶牛粗饲料，特别是优质粗饲料不足，不仅是全国性问题，更是南方地区的大问题。高能饲草饲料系列产品具有原料来源广泛的特点，已在江苏等地奶牛场、鹿场大面积推广应用，是江苏省奶业协会首批推荐的产品，有望根本解决我国奶牛优质饲草供应不足的难题。     

复合添加剂对奶牛产奶量和繁殖性能的影响

营养对奶牛的发情、配种、受胎、产奶和饲料转化率起着决定性作用，是提高奶牛经济效益的限制性因素，尤其是妊娠和泌乳奶牛更需要营养平衡的日粮。要实现营养平衡，除常规饲草、饲料的科学搭配外，还需要添加某些一般饲料含量不足的微量营养物质，以满足奶牛的正常繁殖和产奶需要．并改善瘤胃牛态环境，提高粗饲料的消化利用。农户饲养奶牛大多均以农作物秸杆等粗饲料为主，其日粮有效营养成分含量少且营养不平衡，严重影响了奶牛生产性能的发挥。为此，我们选择了青岛市奶牛场，在奶牛的混合精饲料中加入复合添加剂，观察其对奶牛产奶和繁…     

复合添加剂对奶牛产奶量和繁殖性能的影响

营养对奶牛的发情、配种、受胎、产奶和饲料转化率起着决定性作用，是提高奶牛经济效益的限制性因素，尤其是妊娠和泌乳奶牛更需要营养平衡的日粮。要实现营养平衡，除常规饲草、饲料的科学搭配外，还需要添加某些一般饲料含量不足的微量营养物质，以满足奶牛的正常繁殖和产奶需要，并改善瘤胃生态环境，提高粗饲料的消化利用。农户饲养奶牛大多均以农作物秸秆等粗饲料为主，其日粮有效营养成分含量少且营养不平衡，严重影响了奶牛生产性能的发挥。为此，我们选择了青岛市奶牛场，在奶牛的混合精饲料中加入复合添加剂，观察其对奶牛产奶和繁…     

我国奶牛饲料产奶净能值测算方法的研究

本文将国内有关的奶牛消化代谢试验和单一饲料消化率试验材料进行整理和统计分析,制定出适合我国实际情况的根据饲料可消化能推算饲料产奶净能的回归公式,完善了我国的奶牛饲养标准。     

奶牛产奶前期营养调控研究

通过对奶牛日粮代谢能、粗蛋白质和粗饲料类型3个营养因素对产奶前期奶牛100d产奶量影响的测定,确定日粮代谢能是起主导作用的因素。本试验ME:11.0MJ/kg,CP:12.0,粗饲料为全株玉米青贮饲料加玉米秸,奶牛100d产奶量可达到2907kg,平均日产奶29.07kg/d,全日粮料奶比为0.69:1,相当于精饲料产奶比0.31:1。根据上述试验结果和吉林西部的气候与饲料资源特点,笔者推荐在奶牛产奶前期生产中使用ME:10.0MJ/kg,CP:10.5的日粮,尽量不使用稻草作为奶牛产奶前期的主要粗饲料。     

中国苜蓿市场分析

苜蓿，学名为紫花苜蓿（MedicagosativaL．）属多年生豆科牧草，产量高，蛋白质含量高，在18％-24％，富含各种氨基酸、维生素、胡萝卜素、叶黄索、钙、磷、果胶、皂甙、异黄酮类等促营养物质，营养平衡而全面。其可消化纤维含量高，优质苜蓿的NDF为40％，ADF30％，干物质消化率为69％，产奶净能1．48Mcal／Kg，相对饲用价值（RFV，％）在150以上。苜蓿寿命长，可达10年以上，高产期一般3-5年，使用期可达5～8年，被誉为“饲草之王”，是饲养奶牛不可缺少的优质粗饲料。     

张家口市塞北管理区种草养畜的成本收益分析

为给华北农牧交错带典型区域张家口市塞北管理区的农、牧业结构调整提供决策支持,在实地调研基础上,对当地种草养畜进行成本收益分析.结果表明:饲草、饲料作物的成本纯收益率为45.2%~125.1%,依次是青贮玉米>青稞>禾本科牧草≥豆科牧草;青贮玉米和多年生牧草的生产成本分别为其购入价格的44.4%~59.1%和48.6%~68.9%;投入不足是限制青贮玉米生产效益提高的主要因子;"全年舍饲"模式下,产奶量4550~6300 kg/头的中、高产奶牛的养殖纯收益为-86.5~1544.2元/头,成本纯收益率为-1.1%~15.5%,盈亏临界产奶量为4588.1~4789.8 kg/头;"舍饲+暖季放牧"模式下,种草养畜(中、高产奶牛)的纯收益为1453.6~3435.2元/头,51.0%以上的纯收益来源于饲草种植,成本纯收益率为22.7%~42.5%,盈亏临界产奶量为2850.0~3182.8 kg/头.     

奶牛试用高能饲草饲料试验情况

优质粗饲料是实现奶牛高产、减少奶牛营养代谢疾病、提高养牛业经济效益的重要物质基础。用高新技术生产的高能饲草饲料。经测定其产奶净能达2．13NND／千克，而且经过高温消毒处理，具有产奶净能高、饲用安全的特点。几年来，经多家单位实际饲喂泌乳牛，效果良好，高能饲草作为优质于草使用，能提高奶牛的产奶量和奶品质，经济效益显著。目前，农村产业结构调整，农民饲养奶牛逐步增多。使用未经处理的秸秆，营养价值低。对生产带来的障碍越来越明显。为体现集团公司龙头企业在农业生产中的地位和作用。集团公司承担了国家科技攻关计划《南方农区奶业现代化生产技术集成与产业化示范》项目。把秸秆的处理和利用作为该项目内容之一。集闭公司在原仙林奶牛场进行了试用高能饲草饲料试验，使用高能饲草饲料．减少部分苜蓿干草和部分玉米青贮。经64天试验．结果是试验组牛比对照组牛降低日粮饲料费用0．24元，平均每天多产奶2．47千克／头．每头牛每天增收5．11元，经济效益十分显著。现将试验情况报告如下。     

奶牛小肠蛋白质体系的局限性与氨基酸平衡

现在国内外已将奶牛的可消化粗蛋白体系改进为小肠可消化蛋白质体系,但由于小肠蛋白质的氨基酸组成变异性很大,其CV高达5.6%~19.2%,因而导致可代谢蛋白质的转化效率不稳定,表观效率便会掩盖实际需要。奶牛的第一和第二限制性氨基酸分别为赖氨酸和蛋氨酸,较多研究认为组氨酸为第三限制性氨基酸,但当肝后部提供的组氨酸不能满足产奶需要时,组氨酸可来自体储存的分解,因此尚不能完全确定。据对87个试验结果的统计分析表明,在瘤胃后供给额外的赖氨酸和蛋氨酸,则奶牛的产奶量、乳蛋白量、乳蛋白率均明显增加;对48个试验结果的统计分析结果表明,在可代谢蛋白质被满足供应的基础上,当赖氨酸和蛋氨酸分别达到7.08%和2.35%时,乳蛋白质产量达到最高点。法国INRA在其试验的基础上,确定小肠可消化真蛋白质中的赖氨酸和蛋氨酸的适宜含量为7.3%和2.5%,由于我国现行的是小肠可消化粗蛋白质体系,故建议其赖氨酸和蛋氨酸的含量为6.0%和1.9%,但须评定瘤胃微生物蛋白质和饲料非降解蛋白质的赖氨酸和蛋氨酸含量,并调整日粮使其达到平衡。     

日粮粗蛋白质及能量水平对架子牛肥育效果影响的研究

试验采用2～3岁,体重在305～350kg的架子牛,按高蛋白高能量(精料1号)、高蛋白低能量(精料2号)、低蛋白高能量(精料3号)、低蛋白低能量(精料4号)四组日粮进行为期90d的肥育。试验结果表明,当架子牛体重在320～420kg的情况下,高蛋白高能量日粮组日增重明显高于其他三组(P<0.01)。当体重超过420kg以上时,高蛋白高能量组日增重与低蛋白高能量组比较差异显著(P<0.05),与其他两组比较差异极显著(P<0.01)。从经济效益上分析,由高到低,依次为高蛋白高能量、低蛋白高能量、高蛋白低能量、低蛋白低能量。结论:架子牛肥育前期日粮(按风干计)的粗蛋白质水平应达到13.5%～14.0%,消化能在11.60～11.70MJ/kg;肥育后期粗蛋白质水平应达到12%,消化能要在11.80MJ/kg以上。     

施氮和刈割对辽西北退化草地牧草产量和品质的影响

施氮和刈割是天然草地有效管理方式.为探究退化草地高效利用方式,以辽宁省西北部农牧交错区退化草地为研究对象,设置氮肥添加(0、10 g N·m-2·a-1)和刈割处理(留茬高度3、6、12 cm、不刈割),通过连续两年测定牧草产量和22项牧草品质指标,分析施氮和刈割对辽西北退化草地牧草产量和品质的影响.结果表明:1)施氮...     

生长犊牛蛋白质需要量及其代谢规律规定

选择10月龄鲁西黄牛×利木赞杂交公牛15头，采用饲养试验和消化代谢试验，研究生长犊牛的蛋白质需要量及其代谢规律。试验结果表明，生长犊牛对日粮蛋白质的消化率为61.37%，沉积率为27.62%。生长肉牛代谢粪氮(MFN)和内源尿氮(EUN)的排出量分别为0.40g／kgw     

不同牧草在奶牛瘤胃内的降解规律

试验用尼龙袋法研究了不同种类牧草(黑麦草Lolium multiflorum、羊草Leymus chinese、返青期和盛花期紫花苜蓿Medicago sativa)的干物质(DM)、粗蛋白(CP)和粗纤维(CF)的在奶牛瘤胃内动态降解率变化规律.结果表明:在相同培养时间段内,返青期的紫花苜蓿DM的降解率显著高于黑麦草、羊草和盛花期的紫花苜蓿;不同生长期的紫花苜蓿其DM、CP的降解率差异显著(P<0.05),且返青期高于盛花期;各种牧草在48 h 的 CP 降解率都趋于平稳;经相关分析,各种牧草的DM、CP表现为强正相关关系.     

Studies on the use of lucerne silage source for high-milk-producing dairy cows

Studies on the use of lucerne silage as a forage source for high-yielding dairy cows. It was the main objective of this study to investigate effects of lucerne silage inclusion in maize silage-based rations on dry matter intake, milk yield and metabolic parameters of high yielding dairy cows. Three total mixed rations (TMR) were used. They contained as the main forage source on a dry matter basis 41.5% maize silage and 12% grass silage (ration maize) or 18% maize silage and 29% of either grass silage (ration grass) or lucerne silage (ration lucerne). Organic matter digestibility, determined with wether sheep, was 77 and 65% for the grass and the lucerne silage, respectively. Each TMR was fed to 4 wether sheep to determine crude nutrient digestibilities. The content of net energy for lactation (NEL), as calculated from digestible crude nutrients, was (MJ/kg dry matter (DM)): 7.1 (maize), 7.2 (grass) and 6.8 (lucerne). Based on the results of a chemical fractionation of crude protein it was calculated that the content of utilisable crude protein (nXP) was not below 167 g/kg DM and that the N balance in the rumen was not negative for all 3 TMR. The TMR were fed for 169 days to at least 28 dairy cows per treatment which were in their first half of lactation. Feed intake, milk performance data and physiological indicators were measured for each individual cow. The DM intake was significantly higher in treatment lucerne (23.2 kg/d) than in treatments grass (21.2 kg/d) and maize (22.6 kg/d). Daily intakes of NEL and nXP were significantly lower in treatment grass than in the other two treatments. Milk yield was significantly higher in treatment maize (41.7 kg/d) than in treatments grass (37.3 kg/d) and lucerne (38.5 kg/d). This was associated with a significantly lower milk fat content in treatment maize (3.5%) in comparison with the other two treatments (3.9% each). Milk protein content was unaffected by treatment (3.4% on average). Similarly, the acetone content of milk was not significantly different between treatments. The beta-hydroxybutyrate content of the deproteinized blood was significantly higher in treatment lucerne at start of lactation, but this difference disappeared in subsequent parts of the experimental period. Measurements of back fat thickness indicated mobilisation and retention of energy by cows during the experimental period to be similar in all treatments. It is concluded that lucerne silage is a suitable forage source for high yielding dairy cows in spite of its low digestibility.     

Studies on the evaluation of feed protein for ruminants. 1. Passage of nitrogen fractions to the duodenum of dairy cows fed different protein and carbohydrate sources

The duodenal passages of non-ammonia nitrogen (NAN), amino acid N (AA-N) and microbial N (MN) were measured in seven duodenal fistulated dairy cows (6130 kg FCM/305 d) during lactation receiving 30 different rations similar to those used in dairy practice. The rations consisted of roughage (protein-rich silages, hay) and concentrate mixture (corn, barley, oat) in a ratio of 60:40 on a DM basis or roughage/concentrate mixture/fodder beets in the proportions 60:20:20 or 60:0:40 respectively. N supplements consisted of soya bean meal and peas meal (untreated or treated with formaldehyde in each case), rapeseed meal, fish meal and urea. DM intake varied between 9.6 and 19.1 kg/d, the crude fibre content between 166 and 270 g/kg DM, the crude protein (CP) content between 111 and 184 g/kg DM, the AA content (N basis) of the CP between 51 and 82%, the unfermentable CP content of the CP between 23 and 49% and the organic matter digestibility between 70 and 79%. The duodenal passage of NAN was 24.2 +/- 2.7 g/kg DM intake, 34.9 +/- 4.1 g/kg apparently digestible organic matter (in total tract, DOM), 43.3 +/- 5.5 g/kg apparently digestible carbohydrates or 4.2 +/- 0.5 g/MJ net energy fat, (y +/- s, n = 90). The value measured for AA-N was 16.8 +/- 2.9 g/kg DM intake, and that for RNA-labelled microbial CP was 146 +/- 26 g/kg DOM. NAN passage (g/kg DM intake) correlated more closely with the duodenal digesta flow rate (DFR) (kg digesta/kg DM intake) as an intrinsic animal factor (r = 0.78) and with the rumen content dilution rate (RDR) (passage of microbial-free organic matter at duodenum/kg BW0.75.h) as a ration dependent factor (r = 0.64) than with the UDP fraction (% of ration CP) (r = 0.50) or other ration parameters. It was concluded that the specific effect of protein concentrates in mixed rations on duodenal NAN yields in lactating dairy cows is lower than hitherto assumed. The duodenal NAN yield of a single feedstuff or ration (g/kg DM) in cows is dependent on animal and feeding factors. The DFR could represents a suitable target for breeding activities.     

Nutrient digestibility and prediction of metabolizable energy in total mixed rations for ruminants.

The aim of the present study was to determine equations that predict ME in total mixed rations (TMR) based on routine methods. The ME content of 30 TMR for dairy cows was determined based on digestible crude nutrients obtained with wether sheep. Concentrations in the TMR (in g/kg DM) varied between 118 and 234 for crude protein, 26 and 48 for crude lipid, 131 and 250 for crude fibre, 281 and 488 for NDF, and 173 and 304 for ADF. Gas production ranged from 40.7 to 54.1 ml/200 mg DM, and enzymatically degraded organic matter from 652 to 800 g/kg DM. Digestibility [%] ranged from 68.6 to 84.0 for organic matter, from 55.6 to 84.3 for crude lipid, from 55.0 to 77.8 for crude fibre, from 57.6 to 77.0 for NDF and from 53.1 to 79.6 for ADF. ME ranged from 9.6 to 11.9 MJ/kg DM, and NEL from 5.7 to 7.4 MJ/kg DM. ME content was highly correlated with the concentration of both crude fibre and enzymatically degradable organic matter as well as with organic matter digestibility. A multiple regression equation based on crude fibre and crude lipid predicted ME with a reasonable goodness of fit (r2 = 0.81; s(y.x) = 2.4%). The inclusion of other nutrients, of neutral and acid detergent fibre, neither of gas production did improve the goodness of fit. The best prediction was achieved with inclusion of enzymatically degraded organic matter (r2 = 0.90; s(y.x) = 1.7%).