饲料中添加高水平的玉米秸秆对覆膜尿素和钠基膨胀土的消化率、瘤胃发酵作用和微生物蛋白质产量的影响

试验选用安有瘤胃瘘管的杂交羊(小尾寒羊×杜泊羊)4只,采用4×4拉丁方试验设计,旨在评价覆膜尿素(PCU)和钠基膨润土(SB)对高水平饲喂羊的采食量、营养物质消化率、氮沉积、瘤胃发酵和微生物氮的影响。每天7:00和19:00提供含有60%玉米秸秆和40%精料的等氮等热量的饲粮给4只羊,自由采食以确保5%的口服补液。对照组(CON)、PCU组(豆粕中被1.8%的覆膜尿素代替)、SB组(CON组额外添加SB 2%)、PCUSB组(PCU组额外添加SB 2%)。与其他处理组相比,PCU组的羊有较高的有机物消化率(P0.05)、氮消化率(P0.01),但对其他营养物质消化率和干物质采食量(DMI)无影响。SB组只影响氮的消化率。试验组对氮摄入量和排泄量物有影响,PCU组的氮沉积较高(P=0.09)。此外,试验组嘌呤衍生物(PD)、微生物氮、PH和总挥发性脂肪酸无显著变化。PCU组丙酸比例极显著增加(P0.01),PCUSB组的丙酸的比例没有改变。PCU组NH3-N的水平不断升高,在喂奶后3 h达到最高水平,且较高水平维持了7 h。不同处理组在玉米秸秆瘤胃动力学上无显著影响,与CON和PCUSB组相比,PCU提高了玉米秸秆干物质的有效降解率(ED)(P0.05),以0.02或0.04流速通过瘤胃,但与CON组相比,SB组提高了ED,以0.06流速通过瘤胃。因此,覆膜尿素作为一种新型非蛋白氮可以替代高水平玉米秸秆中的豆粕,提高有机物、氮的消化率和干物质的有效降解率。此外,在覆膜尿素中添加SB对营养物质的消化率、氮沉积、微生物氮、瘤胃发酵和干物质有效降解率物无显著影响。     

构树嫩枝叶青贮与全株玉米青贮体外瘤胃降解率对比研究

试验旨在探讨构树嫩枝叶青贮与全株玉米青贮体外瘤胃降解率,比较2种粗饲料体外瘤胃降解率的优劣.试验选用4头肉牛[体重(600.2±42.5)kg]提供瘤胃液,设置2种饲料(全株玉米青贮、构树嫩枝叶青贮),在肉牛体外瘤胃中消化36、48、72 h,2种饲料每个消化时间各设4个重复,2个平行.采用体外消化法测定3个不同降解时...     

玉米秸秆的青贮及利用

<正>青贮饲料是将切碎的新鲜玉米秸秆在密封无氧的条件下通过微生物厌氧发酵和化学作用而成。青贮玉米秸秆能有效地保持玉米秸秆的青绿状态。青贮饲料气味芳香、柔软多汁、适口性好,十分适于饲喂牛羊,可提高家畜采食量,促进牛羊消化腺分     

玉米青贮成熟度和混合程度对干奶期奶牛瘤胃和消化道的影响

试验旨在探索成熟度不同、混合度不同的全植物玉米青贮饲料对其淀粉含量、中性洗涤纤维(NDF)含量、蛋白质消化程度及在干奶期奶牛瘤胃发酵程度的影响。将4头干奶期的荷斯坦奶牛植入瘤胃瘘管、十二指肠近端瘘管,设计4×4拉丁方阵,饲喂4种混合程度不同(较硬与较松软)和成熟度不同(早期与晚期)的玉米青贮饲料。早期成熟到晚期成熟的淀粉含量增加(234.5到348.5 g·kg-1),而全消化道(99.7%到94.5%)和瘤胃(91.3%到86.5%)中淀粉消化率显著降低。在混合物中,瘤胃淀粉消化率的降低与成熟度增加相关。成熟、混合与成熟×混合对全消化道NDF消化率、瘤胃NDF消化率、氮的真消化率及瘤胃中有机物含量或微生物合成量没有影响。成熟后收获能增加瘤胃氨含量、总挥发性脂肪酸浓度、乙酸/丙酸比值,但对p H没有影响。试验结果表明,推迟收获日期能调整奶牛对淀粉消化率和NDF的吸收比例。调整玉米的收获日期能调整瘤胃消化淀粉总量,这能被用于调整反刍动物的营养吸收。     

不同品种甜高粱青贮体外产气量及瘤胃降解特性比较

【目的】研究不同品种甜高粱青贮饲料在瘤胃内消化降解情况,评价其营养价值.【方法】以‘丽欧’‘吉甜1号’‘大力士’和‘兰巴斯’4个品种甜高粱青贮为材料,采用体外产气法和体内尼龙袋法,研究了4个品种甜高粱青贮体外发酵产气量及干物质(DM)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的瘤胃降解率.【结果】‘丽欧’和‘吉甜1号’甜高粱青贮体外发酵产气量72 h时均超过了50 mL,显著大于‘大力士’和‘兰巴斯’(P<0.05);‘丽欧’甜高粱青贮饲料DM瘤胃降解率最大,显著高于其他3个品种(P<0.05);‘丽欧’和‘吉甜1号’甜高粱青贮NDF和ADF瘤胃降解率较大,显著大于‘大力士’和‘兰巴斯’(P<0.05).【结论】‘丽欧’甜高粱青贮瘤胃消化性最好,表明其青贮营养价值较高,其次是‘吉甜1号’和‘大力士’,‘兰巴斯’甜高粱可消化性较差,青贮营养价值较低.     

不同青贮方式对紫花苜蓿青贮饲料饲用品质的影响

试验共设置地上青贮、地下青贮、青贮堆3个处理,发酵60 d后,开窖取样。对不同方式处理的苜蓿青贮饲料的营养成分、发酵品质及体外消化进行分析。结果表明,地上青贮饲料营养成分保存较好,感官得分最高,为16分;青贮堆苜蓿青贮饲料的粗蛋白质含量显著低于其他处理(P0.05),而中性洗涤纤维、酸性洗涤纤维含量显著高于其他各处理(P0.05),p H、氨态氮占总氮比例均显著高于其他处理(P0.05),分别为4.71、9.15%;地上青贮饲料营养体外消化率较高,与地下青贮差异不显著(P0.05)。综合考虑发酵品质、体外消化率,认为规模化生产中,最佳的方式为地上青贮。     

稻草饲料采食量与纤维物质瘤胃内消化的关联

用3头装有瘤胃瘘管的绵羊,研究了稻草饲料采食量与瘤胃内纤维质消化的关联。窟胃内纤维质的消化用半体内法(尼龙小包技术)测定,以可消化含量(PED)、PED的消化速度常数(kd)、消化迟延时间(LT)以及通过速度常数(kp)等指标进行了描述。稻草饲料采食量与细胞壁成分或酸性洗涤纤维的PED或kd均无显著相关,而与两者之积(PED×kd)和kp有显著相关。作者动态地结合PED,kd,kp三者,用下式描述了瘤胃内纤维质的消失:[PED/(kd+kp)+(100-PED)/kp],并把此式求得之值命名为饲料纤维质的瘤胃滞留系数。稻草饲料的采食量与细胞壁成分的瘤胃滞留系数有极显著的负相关(r=-0.90***)。这些结果意着味,通过改善瘤胃内纤维质的消化和通过加快瘤胃内饲料残渣的排空,将能提高稻草饲料的采食量。     

添加玉米秸秆对甜菜渣青贮品质和体外消化率的影响

以甜菜渣和玉米秸秆为青贮原料,按照不同质量比(鲜样)混合青贮,分析添加玉米秸秆对甜菜渣青贮饲料化学成分、发酵品质和体外消化率的影响。结果表明:甜菜渣直接青贮其乳酸含量较低(0.67%),乙酸含量较高,为乙酸发酵类型;添加玉米秸秆显著降低了青贮饲料的pH(P0.05),显著提高了青贮饲料的乳酸含量(P0.05),9∶1和8∶2处理组显著降低了氨态氮的生成量(P0.05),其发酵类型均为乳酸发酵型。通过flieg评分体系对不同组合进行评价,其等级均为良好。添加玉米秸秆后除9∶1处理组以外,其他处理均显著降低了青贮饲料粗蛋白含量,提高了中性洗涤纤维和酸性洗涤纤维含量,表明添加玉米秸秆降低了青贮饲料的营养成分;添加玉米秸秆后其体外干物质消化率均显著低于ck(P0.05),除9∶1处理组以外其体外中性洗涤纤维、酸性洗涤纤维和粗蛋白消化率均显著低于ck(P0.05)。综合各项指标,认为甜菜渣和玉米秸秆的最佳混合青贮比例为90%甜菜渣+10%玉米秸秆(9∶1)。     

优质全株青贮玉米制作关键技术环节

正青贮玉米作为牛羊的基础饲料在草食畜牧业生产中起着重要作用。其生物产量高,可消化营养多,适口性好,一年四季可以均衡供应鲜绿多汁的青饲料。青贮对牛羊采食速度,瘤胃微生物环境的稳定和身体健康都有重要作用。欧洲畜牧业发达国家玉米种植面积的80%以上都作为青贮饲料使用。美国青贮玉米种植面积占玉米种植面积的40%以上。据统计籽粒玉米的收获指数为0.45,青贮玉米的收获指数可以     

刈割时间对青贮玉米秸秆饲料营养成分的影响

国外较多的研究是从整株玉米青贮的角度研究不同品种和收获成熟期对青贮饲料营养价值的影响,而国内对青玉米秸秆青贮的研究报道多涉及提高青贮饲料的品质,为此试验选用收刈时间(生长期)为92、94、96、98、100、102和104d的高油115玉米青秸秆调制青贮饲料,研究玉米秸秆收刈时间对青贮饲料营养成分的影响,结果表明收刈时间明显影响青贮饲料的氨态氮、CP和NDF含量,尤其是明显影响青贮饲料的有机物体外降解率,收刈时间对青玉米秸秆青贮饲料的乳酸、丁酸含量和ADF含量没有明显的影响(p>0.05)。     

Barley forages for modern global ruminant agriculture: A review

Ruminants have evolved on forages that comprise major portions of most modern dairy and beef cattle diets. Cattle require minimum amount of effective fiber to maintain healthy rumen conditions. However, high fibre levels limits feed intake. Dietary fiber levels and physical properties contribute to such hypophagia. Forage bulkiness, particle size, lignification and rumen passage rate determine fiber quality. Barley forage (BF, Hordeum vulgare, L.) serves dairy diets where and when alfalfa or corn silages are less accessible. Being lower in protein, intermediate in soluble protein, and higher in starch and cellulose, barley silage (BS) is a suitable replacement for alfalfa silage. Barley forages have usually lower fiber levels among winter cereal crops. Barley forages may not reduce feed intake as much as other cereal crops, notably triticale and oats. Beef studies suggest superior or similar weight gain and feed efficiency by feeding BS versus wheat, triticale and oat silages. Growth response to BS appears comparable to corn silage. Reduced BS particle size reduces chewing activity in lactating cows, and even with adequate fiber intake has little effect on milk fat. Inoculants containing Lactobacillus buchneri, Lactobacillus plantarum, Pediococcus pentosaceus, and Propionibacterium freudenreichii along with carbohydrases can lower silage pH and improve organic acids production and silage aerobic stability. Altered barley silage chop length alters chewing activity but not necessarily rumen pH. Maturity stage affects nutritional value of BF due to altered protein and fiber contents and rumen fermentation patterns. Genetic variance among BF cultivars can affect nutrient profiles and rumen digestibility. Barley forages are cost-effective entities along with alfalfa hay and silage and corn silage for environmentalist ruminants to host optimal rumen and peripheral nutrient metabolism. Adequate effective fiber with sufficient but not very high fermentable starch, and modest degradable proteins make BF a unique ingredient for the sustainable modern ruminant production.     

牛瘤胃液稀释率的研究

瘤胃液稀释率会影响微生物蛋白质的产量、消化率、采食量,也会改变发酵类型。本试验采用3头成年瘤胃瘘管牛,喂以三种不同的日粮,以聚乙烯二醇(PEG)所测定的稀释率,饲喂苜蓿干草者为0.1321/hr,饲喂50％干草+50％精料者为0.10362/hr,饲喂玉米青贮者为0.12917/hr。瘤胃液在瘤胃中停留时间与稀释率成反比。瘤胃液容积,母牛比阉牛要小,瘤胃液外流率也以喂干草者为高.     

高油玉米秸秆青贮发酵动态及青贮浸提液对活体外瘤胃发酵的影响

通过研究高油玉米秸秆青贮发酵过程中营养成分和发酵参数变化的动态(试验1),以及青贮浸提液对活体外瘤胃发酵的影响(试验2),初步探明导致高油玉米秸秆青贮提高瘤胃发酵程度的因素。试验1结果显示发酵1周内,可溶性糖损失50%以上,pH降到4.0以下;乳酸含量在6周内逐步升高,而后保持不变,其他营养成分保持稳定;试验2结果表明,添加青贮浸提液后与对照组相比,最大产气量显著增加(P<0.000 1),产气速度加快(P<0.000 1),产气延滞期缩短(P=0.000 8)。其中青贮浸提液灭菌处理与否不影响产气动态参数。添加2种青贮浸提液会导致活体外人工瘤胃发酵pH显著降低(P<0.000 1)。对照组活体外瘤胃发酵液中乙酸摩尔分数最低(67.79%),其次为添加未处理浸提液组(78.48%)和灭菌浸提液组(80.19%),并且3个处理组差异显著(P<0.000 1)。丙酸摩尔分数也差异显著(P<0.000 1),其中对照的丙酸摩尔分数最高,达到21.76%,而其他2个处理组分别为8.81%和6.84%。对照组中异丁酸和异戊酸的摩尔分数均最高,分别为0.66%和0.85%。结果表明,高油玉米秸秆青贮在1周内发酵过程变化很大,发酵6周后,进入稳定阶段。添加青贮浸提液影响活体外瘤胃发酵模式,高油玉米秸秆青贮浸提液的营养成分可能是影响瘤胃微生物发酵的主要因素。     

Effect of lactic acid bacteria and propionic acid on conservation characteristics,aerobic stability and in vitro gas production kinetics and digestibility of whole-crop corn based total mixed ration silage

This study was conducted to evaluate the effect of lactic acid bacteria and propionic acid on the fermentation quality, aerobic stability and in vitro gas production kinetics and digestibility of whole-crop corn based total mixed ration(TMR) silage. Total mixed ration was ensiled with four treatments:(1) no additives(control);(2) an inoculant(Lactobacillus plantarum)(L);(3) propionic acid(P);(4) propionic acid+lactic acid bacteria(PL). All treatments were ensiled in laboratory-scale silos for 45 days, and then subjected to an aerobic stability test for 12 days. Further, four TMR silages were incubated in vitro with buffered rumen fluid to study in vitro gas production kinetics and digestibility. The results indicated that all TMR silages had good fermentation characteristics with low pH(3.80) and ammonia nitrogen(NH_3-N) contents, and high lactic acid contents as well as Flieg points. Addition of L further improved TMR silage quality with more lactic acid production. Addition of P and PL decreased lactic acid and NH_3-N contents of TMR silage compared to the control(P0.05). After 12 days aerobic exposure, P and PL silages remained stable, but L and the control silages deteriorated as indicated by a reduction in lactic acid and an increase in pH, and numbers of yeast. Compared to the control, addition of L had no effects on TMR silage in terms of 72 h cumulative gas production, in vitro dry matter digestibility, metabolizable energy, net energy for lactation and short chain fatty acids, whereas addition of PL significantly(P0.05) increased them. L silage had higher(P0.05) in vitro neutral detergent fiber digestibility than the control silage. The results of our study suggested that TMR silage prepared with whole-crop corn can be well preserved with or without additives. Furthermore, the findings of this study suggested that propionic acid is compatible with lactic acid bacteria inoculants, and when used together, although they reduced lactic acid production of TMR silage, they improved aerobic stability and in vitro nutrients digestibility of TMR silage.     

Effects of formic acid and corn flour supplementation of banana pseudostem silages on nutritional quality of silage,growth, digestion,rumen fermentation and cellulolytic bacterial community of Nubian black goats

The objective of this study was to evaluate the effects of adding formic acid and corn flour supplementation to banana pseudostem silages on the nutritional quality of these silages, growth, digestion, rumen fermentation and cellulolytic bacterial community of Nubian black goats fed these silages. Banana pseudostem silage was prepared either conventionally without any additives(CON) or mixed with 0.6% formic acid(F), 10% corn flour(C), or both(F+C). Four experimental diets containing 40% of the corresponding silages were designed with roughage to concentrate ratio of 50:50(dry matter(DM) basis). A total of 48 Nubian black castrated goats(body weight(BW),(22.64±1.82) kg; 4-mon-old) were randomized into one of the four treatment groups with 12 replicates of one castrated goat per replicate for each treatment in a completely randomized design. Each group was fed on one of the four experimental diets for 40 days. A factorial arrangement of treatments of 2(formic acid levels: 0 and 0.6%)×2(corn flour: 0 and 10%) was adopted. Formic acid supplementation increased(P0.05) average daily gain, as well as lactic acid, propionate and butyric acid and water-soluble carbohydrate concentrations, but decreased(P0.05) the feed conversion rate, p H value, acetate/propionate ratio, and butyric acid concentration relative to the CON group. Corn flour supplementation increased(P0.05) the apparent digestibility of crude protein, neutral detergent fiber, and non-fibrous carbohydrate and Fibrobacter succinogenes, Ruminococcus albus, and Butyrivibrio fibrisolvens populations, but decreased(P0.05) the Ruminococcus flavefaciens population relative to the CON group. There were no F×C treatment interactions(P0.05) for any of the other indices except for the apparent digestibility of non-fibrous carbohydrate(NFC)(P0.05). The results demonstrated that adding 0.6% formic acid and 10% corn flour supplementation to banana pseudostem silages improved the nutritional quality of these silages and enhanced the growth performance of Nubian black castrated goats by improving apparent nutrient digestibility, and regulating ruminal fermentation and bacteria populations.     

Effects of Lactobacillus plantarum and fibrolytic enzyme on the fermentation quality and in vitro digestibility of total mixed rations silage including rape straw

The aim of the current study was to investigate the effects of a lactic acid bacteria inoculant(Lactobacillus plantarum, LP), fibrolytic enzyme(EN), combination of LP and EN(LP+EN) on fermentation quality, nutritive characteristics and in vitro digestibility of total mixed ration(TMR) silages containing 0, 7.5 and 15.0%(on dry matter basis) of rape(Brassica campestris L.) straw(RS)(denoted as CTMR, LTMR and MTMR, respectively). After ensiling for 60 days, TMR silages without additives were well preserved, but MTMR had higher p H than CTMR and LTMR. There were no differences in other parameters of fermentation quality, microbial composition, nutrition and in vitro digestibility between CTMR and LTMR except for yeast and mold number and crude protein(CP) content. CTMR and LTMR silage had higher CP content, in vitro neutral detergent fiber digestibility(IVNDFD) and in vitro acid detergent fiber digestibility(IVADFD), lower acid detergent fiber(ADF) content than MTMR silage. LP and EN decreased p H and increased dry matter(DM) recovery of TMR silages. LP+EN improved the fermentation quality, nutritive characteristics and in vitro digestibility of TMR silages, showed by lower p H, ADF content, higher lactic acid content, in vitro dry matter digestibility(IVDMD) and IVNDFD. Therefore, It was suggested that TMR silage contained 7.5% RS on a DM basis and treated with LP+EN can be as a useful feed for ruminant.     

葡萄渣对人工瘤胃发酵的影响

利用Rusitec-S型连续培养系统,研究葡萄渣含量分别为0%、8%、12%、16%的日粮对人工瘤胃发酵的影响.结果表明:日粮中葡萄渣含量为16%可显著降低瘤胃挥发性脂肪酸(VFA)、干物质(DM)、有机物(OM)、粗蛋白(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的瘤胃降解率和NH3-N浓度(P<0.05);日粮中葡萄渣含量为8%、12%对人工瘤胃VFA、pH、DM、OM、NDF、ADF的降解率和NH3-N浓度无显著的影响,但葡萄渣含量为12%时可显著降低瘤胃NH3-N浓度和CP的瘤胃降解率(P<0.05).因此,日粮中添加葡萄渣以12%以下为宜.     

水稻秸青贮对反刍动物甲烷排放的影响

采用2个3×3拉丁方试验设计,利用SF6示踪技术分别测定了青年母牛不同饲养水平(维持和生长)下饲喂青贮稻秸、氨化稻秸以及干稻秸的甲烷排放量,从而评价了水稻秸青贮在减少甲烷排放量上的作用。结果表明:维持水平下,饲喂青贮稻秸和氨化稻秸可有效地降低试验牛每天的甲烷排放以及每千克干物质采食量的甲烷排放,并且与干稻秸组之间差异显著(P<0.05)。甲烷排放量由大到小为干稻秸、氨化稻秸、青贮稻秸。生长水平下,粗饲料的瘤胃降解率越高,日粮中添加精料越有助于纤维的发酵,表现为单位(每天或者每采食1 kg干物质)甲烷气体排放青贮稻秸组均高于干稻秸组。     

颗粒精料对黑白花公犊瘤胃pH值和粗饲料消化的影响

用4头装有瘤胃瘘管和十二指肠T形瘘管的黑白花公犊(体重75-85kg)研究颗粒精料对瘤胃pH值和粗饲料消化的影响.试验结果表明。颗粒精料期(Ⅱ期)瘤胃平均pH值以及全天最高和最低pH值均明显高于粉状精料期(Ⅰ期),而Ⅰ期pH值低于6.7、6.5、6.3的百分比时间分别是Ⅱ期的1.65、2.27、3.66;Ⅱ期pH 7-5和pH 6-5的瘤胃缓冲容量均明显增大(P<0.01),Ⅱ期干物质(DM)、有机质(OM)、酸性洗涤纤维(ADF)、纤维素的消化量和消化率分别提高了69.35％(P<0.01)、60.61％(P<0.01)、49.37％(P<0.01)、59.02％(P<0.01)和13.03％(P<0.01)、10.61％(P<0.05)、6.31％(P<0.05)和7.94％(P<0.01),对瘤胃pH总挥发性脂酸及各酸以及乙酸/丙酸比值(A/P)、氨氮浓度等动态变化均进行了测定和分析。试验结果还表明,瘤胃pH的变化与ADF和纤维素的消化成强相关(r=0.6357,P=0.01和r=0.6591,P=0.01)。