半干苜蓿青贮在奶牛生产上的应用

<正>苜蓿作为优质粗饲料,在奶牛生产中起到重要作用,近几年垦区种植的苜蓿面积达到十余万亩,由于气候的原因,苜蓿晒制干草容易受到雨淋造成损失且苜蓿品质下降,青贮的方式可以缓解雨季对苜蓿收获造成的影响。但奶牛生产中苜蓿干草应用的较多,苜蓿青贮是否可以替代奶牛日粮中的苜蓿干草,苜蓿青贮饲喂奶牛的效果如何少见报道。本文分析总结了在垦区奶牛养殖场泌乳奶牛日粮中用半干苜蓿青贮替代苜蓿干草饲喂奶牛的试验,旨在为半干苜蓿青贮在奶牛生产上的应用提供参考依据。     

苜蓿干草在高产奶牛日粮中适宜添加量的研究

 36头 2～ 4胎的荷斯坦奶牛随机分为 3组 ,各组产奶量、体重、胎次、泌乳天数 (DIM)差异不显著。 3组奶牛日粮中苜蓿干草的添加量分别为 3kg(对照 )、6kg和 9kg,相应的日粮干物质 (DM)中粗蛋白含量分别为 16 .4 %、17.9%和 19.4 % ,组间中性洗涤纤维 (NDF)和产奶净能 (NEL)含量相同 ,分别为 37.8%和 6 .7MJ·kg-1DM。结果表明 ,在以苜蓿干草为主的奶牛日粮中提高粗蛋白含量能极显著提高产奶量 (P <0 .0 1) ,干物质采食量 (DMI)显著增加 (P <0 .0 5 ) ,乳脂率、乳蛋白率、乳糖以及干物质含量没有变化 ,乳脂量显著增加 (P <0 .0 5 ) ,乳蛋白量极显著增加(P <0 .0 1) ,体细胞数 (SCC)显著下降 (P <0 .0 5 )。在日粮NDF相同的条件下用苜蓿干草替代玉米青贮 ,不会降低乳脂率。在奶牛日粮中大量使用苜蓿干草并不增加日粮成本 ,可以大幅度提高经济效益 ,9kg组与对照相比纯增效益最高。苜蓿干草在高产奶牛日粮中的适宜添加量为 9kg。     

不同粗饲料对秦川肉牛生长发育及血液生化指标的影响

【目的】研究不同粗饲料对秦川肉牛生长发育和血液生化指标的影响。【方法】选取20头14月龄体质量无显著性差异的秦川肉公牛(无阉割),按饲喂的粗饲料种类随机分为苜蓿组(苜蓿+青贮+精料)、桑叶组(桑叶+青贮+精料)、麦草组(麦草+青贮+精料)、对照组(青贮+精料),每组5头,饲喂相应的饲料,于育肥前期(14~15月龄)、中期(16~17月龄)、后期(18~19月龄)分别取样,测定不同粗饲料对秦川肉牛日增重和血液生化指标的影响。【结果】桑叶组秦川肉牛日增重显著高于其他3组(P0.05),苜蓿组秦川肉牛日增重显著高于麦草组和对照组(P0.05),麦草组和对照组肉牛日增重差异不显著(P0.05);桑叶组秦川肉牛血清葡萄糖、谷丙转氨酶和甘油三酯含量显著高于其他3组(P0.05),尿素含量显著低于其他3组(P0.05),各试验组秦川肉牛血清总蛋白、白蛋白、球蛋白、白球比、钙和磷的含量差异不显著(P0.05)。【结论】以桑叶、苜蓿作为秦川肉牛肥育粗饲料的优质干草,育肥效果最好,其中桑叶处理组优于苜蓿处理组(P0.05)。桑叶在肉牛育肥过程中完全可以替代苜蓿,而在以"青贮+精料"为基础的日粮中添加麦草,对改善肉牛肥育效果意义不大。     

夏季奶牛的饲养管理

1 改善牛舍和运动场小气候 主要措施:早晚打开门窗、防风帘;在牛舍安装排风扇和高压喷雾降温装置;每天冲洗和经常刷拭牛体;增加运动场凉棚面积。2 改善饲喂方法 ①饲喂日粮要做到体积小、质量优、易消化,并适当增加高能高蛋白饲料,泌乳盛期使用苜蓿青贮;②选择适口性好的饲料。优质干草3kg,优质玉米青贮20kg,新鲜啤酒糟10kg左右;③调整精、粗饲料比     

饲用甜菜茎叶饲喂奶牛的效果研究

对中国荷斯坦泌乳母牛采用正常日粮加饲用甜菜品种甜饲1号鲜茎叶组、正常日粮加甜饲1号鲜叶青贮组、正常日粮组（CK）进行饲喂试验．结果表明，添加饲用甜菜鲜茎叶或青贮叶均能提高奶牛的产奶量和经济效益，以添加鲜茎叶的效果最好，其每头奶牛的日均产奶量为20．5kg，比对照增加2．7、0．9kg／头，日均纯收苴为48．4元／头，比对照提高13．3%．具有广阔的推广应用价值．     

苜蓿干草与玉米秸秆混合饲草对羔羊育肥效果的影响

【目的】依据组合效应原理,研究不同比例的苜蓿(Medicago sative L.)干草与玉米(Zea mays L.)秸秆混合饲草对羔羊育肥效果的影响,筛选适宜的饲草搭配比例,以降低饲草成本,提高养殖效益,缓解饲草供需矛盾。【方法】设置苜蓿干草与玉米秸秆的质量比分别为1∶0,7∶3,3∶2,1∶1,2∶3和3∶7的6组混合饲草,以饲喂玉米秸秆为对照,选择体质量20～25kg的3～3.5月龄健康小尾寒羊21只,按试验要求随机平均分为7组进行单笼饲养,每组每天饲喂一种比例的混合饲草2kg,并补饲0.2kg玉米籽实,正式饲喂期为60d,每天测定1次采食量,每10d测定1次体质量增加情况,饲喂期结束后进行屠宰试验并测定各项屠宰性能指标。【结果】苜蓿干草与玉米秸秆按不同质量比混合饲喂育肥羔羊均可产生明显的正组合效应,对羔羊的采食量、体质量增加情况和屠宰性能均会产生显著影响(P<0.05);综合考虑各项测定指标和经济效益分析结果,认为苜蓿干草与玉米秸秆搭配质量比为1∶1是各饲草组合中的最好组合,与对照组相比,该组羔羊对饲草的采食率和饲草转化率分别提高了26.06%和26.83%,羔羊的总增质量、屠宰率、净肉率及经济效益分别提高了45.87%,14.05%,23.16%和49.20元/只。【结论】苜蓿干草与玉米秸秆按适宜质量比混合饲喂育肥羔羊,可显著提高羔羊的采食量,并明显改善其生产性能和屠宰性能,2种饲草的适宜搭配比例(质量比)为1∶1。     

青贮甜高粱与青贮玉米饲喂奶牛、羊及奶品质的比较研究

为了探索甜高粱在青海高原用作青贮饲料,饲喂奶牛及羊的效果、对奶品质的影响,开展了青贮玉米饲喂奶牛、羊的对比研究及奶品质分析。结果:青贮甜高粱日粮饲喂奶牛,比青贮玉米日粮日产奶量增加2.19kg/头;饲喂3~5月龄羊比青贮玉米日粮日多增重2.01g/只,2~3岁龄羊日多增重29.27g/只;奶品质差异不显著。甜高粱用作青贮饲料优于玉米,是优质饲料作物,应大力推广种植。     

不同营养组合对西藏中国荷斯坦杂交改良奶牛产奶量的影响

目的:分析不同营养组合对西藏中国荷斯坦杂交改良奶牛产奶量的影响。方法:A 组奶牛在饲养管理的基础上饲喂全混合日粮(TMR)15 kg、青稞青干草12kg。B组奶牛在饲养管理的基础上饲喂配合饲料6 kg、青贮玉米秸秆11 kg、青干草6 kg。C 组奶牛在饲养管理的基础上饲喂酒糟9kg、青贮玉米秸秆7kg、青干草6kg。D 组奶牛在饲养管理的基础上采取一般的饲喂方式,每天饲喂配合饲料6kg、青干草6kg。比较四组奶牛的总产奶量和比较四组奶牛的经济效益。结果:四组奶牛中,总产奶量最高的是 A 组,其次是B组、 C 组、D 组。四组奶牛中,头均纯收益最高的是 A 组,其次是B组、 C 组、D 组。差异比较,P0.05,有统计学意义。结论:TMR结合能够青稞青干草喂饲能够有效提高奶牛的产奶量,从而提高经济效益。     

不同日粮影响羊驼胃室Ⅰ、绵羊和西门塔尔牛瘤胃甲烷产量的比较研究

试验选用3只平均体重为42±2.3kg的2岁羊驼、3只平均体重为50±1.7kg的2岁绵羊和3只平均体重为500±20kg的3.5岁西门塔尔牛阉牛,采用3×3拉丁方设计,研究不同日粮(精料+高丹草、新鲜苜蓿、苜蓿干草)对羊驼胃室Ι、绵羊和牛瘤胃甲烷产量的影响。结果表明,对于不同日粮,饲喂新鲜苜蓿日粮羊驼胃室Ι、绵羊和西门塔尔牛瘤胃甲烷浓度显著高于饲喂苜蓿干草日粮和高丹草日粮(P0.05);饲喂高丹草日粮羊驼胃室Ι、绵羊和西门塔尔牛甲烷气浓度显著高于饲喂苜蓿干草组日粮(P0.05)。对于不同动物,饲喂高丹草、新鲜苜蓿、苜蓿干草日粮的西门塔尔牛瘤胃甲烷浓度最高,绵羊次之,羊驼胃室Ι甲烷浓度最低(P0.05)。综合以上结果,比较3种日粮,3种动物饲喂苜蓿干草日粮后的甲烷浓度最低。比较3种动物,饲喂3种日粮的羊驼胃室Ι甲烷浓度最低。说明苜蓿干草更适合动物饲用,羊驼能更好的利用这3种饲草。     

高产奶牛日粮中苜蓿干草适宜添加量的研究

选用30头2～4胎的荷斯坦奶牛随机分为3组,各组产奶量、体重、胎次、泌乳天数(DIM)差异不显著。3组奶牛日粮中苜蓿干草的添加量分别为2kg(对照)、4kg和6kg,相应的日粮干物质(DM)中粗蛋白含量分别为15.6%,17.2%和18.8%,各组间中性洗涤纤维(NDF)和产奶净能(NE)含量相同,分别为37.4%和6.9MJ·kg-1DM。结果表明:在以苜蓿干草为主的奶牛日粮中,提高粗蛋白含量能显著提高产奶量(P<0.05);干物质采食量(DMI)变化不显著(P>0.05),但有增加的趋势;乳脂率、乳蛋白、乳糖以及干物质含量没有显著变化(P>0.05),在奶牛日粮中大量使用苜蓿干草并没有增加日粮成本,但可以大幅度提高经济效益,6kg组与对照相比纯增效益最高。因此苜蓿干草在奶牛日粮中的适宜添加量为6kg。     

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.     

苜蓿青贮对奶牛产奶量、乳品质及养殖效益的影响

[目的]为苜蓿青贮在奶牛养殖中的推广和应用提供科学依据。[方法]以苜蓿青贮替代苜蓿干草,进行饲喂效果比较,探讨苜蓿青贮对产奶量及乳品质的影响。[结果]试验组日均产奶量、乳脂率、乳蛋白率、非脂乳固体率、乳糖率分别比对照组高9.13%、1.73%、0.57%、0.42%、0.38%。[结论]在奶牛日粮中适量添加苜蓿青贮,可以有效提高奶牛的产奶量,同时降低饲料成本,从而提高养殖经济效益。     

混播比例对苜蓿青贮品质的影响

[目的]研究不同比例的无芒雀麦与紫花苜蓿混播对青贮效果的影响。[方法]试验设5个处理,即紫花苜蓿单播、无芒雀麦单播、紫花苜蓿＋无芒雀麦以50％＋50％、60％＋40％和70％＋30％比例混播,分析各处理青贮材料的pH值、CP、NDF、ADF、乙酸、丁酸、乳酸和总酸的变化,研究无芒雀麦与紫花苜蓿不同比例混播对青贮品质的影响。[结果]与单播苜蓿相比,混播可以显著降低青材料的pH值（P〈0．01）、NH3．N／TN值（P〈0．01）和丁酸含量（P〈0．01）,有利于保存青贮物的营养成分。混播还可提高青贮产物中乙酸、乳酸和总酸的含量（P〈0．01）,从而提高苜蓿青贮品质。[结论]以混播处理A（苜蓿50％＋无芒雀麦50％）效果最好,pH值,NH3-N/TN的含量最低,乳酸含量和综合评分最高。     

苜蓿干草替代部分精料对奶牛产奶性能的影响

选择年龄、胎次、分娩季节接近的奶牛20头,随机分为4组,每组5头,分别于每天用0、3、6、9 kg的苜蓿干草替代奶牛日粮中的部分精饲料.结果表明,添加苜蓿干草对奶牛的产奶量和乳蛋白没有显著地影响(P>0.05),但添加组(每天3、6、9 kg)与对照组(不添加苜蓿干草)相比,乳脂率有显著提高(P<0.05).从日粮成本看,用苜蓿干草替代奶牛日粮中部分精料可以降低饲料成本,并且以在泌乳奶牛日粮中每天添加6 kg的苜蓿干草替代部分精饲料的处理最为理想.     

应用DGGE分析秸秆日粮对奶牛瘤胃细菌群落的影响

【目的】通过与苜蓿日粮比较,揭示秸秆日粮模式下瘤胃固液相细菌群落的独特结构。【方法】选择12头健康且体重相似的装有永久瘤胃瘘管的中国荷斯坦奶牛,分别饲喂以玉米秸秆（CS）和苜蓿、羊草、青贮玉米三者混合物（MF）为粗饲料组成的日粮,正饲期第13周连续3 d分12个时间点采集瘤胃固、液相内容物样品。提取微生物DNA后,利用PCR结合变性梯度凝胶电泳技术（DGGE）分析细菌群落结构,并进行聚类分析及差异条带的测序分析。【结果】与MF组相比,CS组奶牛瘤胃固、液相细菌DGGE图谱条带的数目和光密度均有一定差异,两处理组都各有一些稍显优势的条带,CS组优势条带要少于MF组。与MF组相比,CS组液相细菌的香浓多样性指数无差异（P＞0.05）,固相细菌香浓多样性指数显著降低（P＜0.01）;通过对差异条带进行测序,发现与MF组相比,CS组中瘤胃细菌Prevotella sp.、Acetivibrio ethanolgignens和Clostridium sp.减少,并且大量来源于Bacteroidetes、Firmicutes、Tenericutes和Proteobacteria等菌门的未培养细菌有所变化。【结论】秸秆日粮条件下奶牛瘤胃存在独特的细菌群落结构,细菌多样性较低。     

Effect of Different Roughages on Milk Protein and Milk Fat Synthesis in Dairy Cows

The main purpose of this study was to determine the effect of a corn straw or mixed diet on milk production, milk composition and the expression of genes associated with lactation in mid-lactation Chinese Holstein cows. In this study, 10 healthy Chinese Holstein cows were randomly assigned to two groups and fed with different diets respectively, corn straw(CS) or mixed forage(MF) diet. CS group was fed roughage consisting of 53.8% corn straw only and the forge to concentrate(F : C) ratio [dry matter(DM)] was about 40: 60. MF group was fed roughage consisting of 3.7% Chinese wildrye and 23.4% alfalfa hay, the forge to concentrate(F : C) ratio(DM) was 70: 30. All the cows were fed 8 weeks and body weight, dry matter intake, body condition score, fat, protein, lactose, milk yield, total solid and somatic cell count(SCC) were recorded. Quantitative real-time PCR(q RT-PCR) was used to analyze cow mammary gland samples representing two different diets. The results suggested that different diet types had significant effects on milk yield, lactose, milk fat, milk protein, dry matter intake and somatic cell count in dairy cows, and cows fed MF diet improved milk production and lactation performance clearly(P0.05). In addition, m RNA expression of genes ACC, m TOR, STAT5, CSN2, PPARγ, FABP3 and PTEN in MF group was extremely significantly higher than that in CS group(P0.05). m RNA expression of AKT1, FAS, SCD and SREBP1 c in MF group was significantly higher than that in CS group(P0.01). In summary, the milk yield and composition in mixed forage group were significantly improved than those in corn straw group.     

PCR-DGGE方法分析玉米及苜蓿青贮动态发酵体系中菌群多样性

[目的]探讨玉米青贮和苜蓿青贮动态发酵过程。[方法]以玉米和苜蓿为青贮原料,利用氯化苄方法对青贮中微生物基因组DNA进行提取,以P2f和P3r为引物扩增目的片段并利用PCR—DGGE方法对玉米青贮及苜蓿青贮进行动态发酵多样性研究。[结果]玉米青贮的pH值在发酵过程中维持在4．0～4．5,而苜蓿青贮则维持在5．5—6．0。PCR-DGGE分析显示2种物料青贮在0和1d、3和7d、20和60d相似性均很高,并且它们具有基本相似的谱带类型,其中条带1、3、13、14、17、21、22为所有样品共有,只是亮度上有差异。DGGE研究结果表明大多数序列代表乳酸菌（LAB）类细菌,并以Lactobacillus类最多;其次为Lactococcus和Weissella。[结论]该研究为青贮添加剂的制作奠定基础。     

Diversity shifts of rumen bacteria induced by dietary forages in dairy cows and quantification of the changed bacteria using a new primer design strategy

The partial 16 S r RNA gene sequences(100 to 500 bp) were widely used to reveal rumen bacterial composition influenced by diets, while quantification of the changed uncultured bacteria was inconvenient due to difficult designing of specific primers based on short sequences. This study evaluated the effect of forage resources on rumen bacterial diversity and developed new strategy for primer design based on short sequences to quantify the changed uncultured bacteria. Denaturing gradient gel electrophoresis(DGGE) analysis and subsequent band sequencing were used to reveal the distinct rumen bacteria composition in cows fed with two forage sources(single corn stover vs. mixed forages including alfalfa hay and corn silage). The bacterial diversity in the rumen of dairy cows fed with corn stover was lower than that with mixed forages(P0.05). The bacterium named R-UB affiliating to uncultured Succinivibrionaceae was identified, and it was abundant in the rumen of cows fed with mixed forages compared to corn stover. The full length 16 S r RNA gene sequences with identity of 97% to the R-UB 16 S r RNA gene sequence were obtained from Gen Bank and used to design specific primers to quantify uncultured bacterium R-UB. All sequences of amplicon from the new primers were of 100% identity to R-UB sequences indicating the high specificity of new primers. Quantitative PCR confirmed that abundance of R-UB in the rumen of cows fed with corn stover was lower than those fed with mixed forages(P0.01). New strategy for designing primers based on partial 16 S r RNA genes to quantify targeted uncultured bacteria was successfully developed. The rumen bacteria descending significantly in the cows fed corn stover compared to those fed mixed forages was identified as uncultured R-UB from Succinivibrionaceae.     

Liquid Chromatography-mass Spectrometry Analysis on Effect of Roughage Types on Liver Metabolic in Dairy Cows

The major objective of this study was to determine the effect of corn straw or mixed diet on the small molecule metabolites of liver and milk production of healthy Chinese Holstein cows during lactation.In this study,metabolomic methods based on ultra performance liquid chromatography-mass spectrometry (LC-MS) were used to study the liver metabolites of dairy cows fed on corn straw diet or mixed diet.Ten healthy Chinese Holstein cows were randomly assigned to two groups,under the same management condition,fed different diets respectively,corn straw group (CS) or a mixture of alfalfa hay and Chinese wild rye hay mixed forage group (MF).All the cows were fed for 8 weeks and recorded body weight,dry matter intake,body condition score,fat,protein,lactose,milk yield and the total solids.Livers were sampled from each cow through a liver puncture needle for analysis of a significant difference in small molecule metabolites in cow liver samples from the two different diets.The results suggested that different diet types had significant effects on liver metabolism and milk components in dairy cows.The contents of milk fat,the total solids,milk protein,lactose,dry matter intake (DMI),milk yield,milk protein (%),lactose (%) and milk fat (%) of the corn straw group were significantly lower than those of the mixed forage group (p0.05);the contents of phosphatidylcholine (PC),histidine,hypoxanthine and mridine in liver tissues of the corn straw group were significantly lower than those in the mixed forage group (p0.05);acetylcarnitine,uric acid,triacylglycerol (TG),acetal phosphatidylcholine (plasmenyl-PC),acetalphosphatidylethanolamine (plasmenyl-PE) and sphingomyelin (SM) of the corn straw group were significantly higher than those in the mixed forage group (p0.05).In summary,cows fed on mixed forage diet significantly improved milk yield and lactation performance clearly.     

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.