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1.
本试验选用30头第一泌乳中期的奶水牛，分为5组(1个对照组和4个试验组)，每组6头。分别饲喂不同水平的高粗料和补充脂肪日粮。结果表明：①奶水牛喂75％粗饲料日粮，减重约2.5kg；奶水牛喂65％粗饲料，高脂肪（7.5%）和中等脂肪（5.0%）日粮，分别增重3和6 kg。体重比较有极显著差异（P<0.01)。②粗饲料水平和脂肪水平对干物质采食量有极显著影响（P< 0.01)。奶水牛喂75％粗饲料与65%粗饲料日粮比较，有较低的干物质采食量(19.7与21.3 kg/d)。奶水牛喂试验日粮，干物质采食量变化相似。③奶水牛喂对照和试验日粮，日均产奶量分别为8.5和8.2 kg，喂高粗料（75%）和高脂肪（7.5%）产奶较少（分别为8.1、8.2、8.25和8.35 kg/d)。在所有试验和对照日粮每千克干物质产奶量差异极显著(P<0.01)。对所有日粮，干物质采食量随时间推移而下降。  相似文献   

2.
以荷斯坦奶牛为试验动物,采用体外批次培养试验法,选择瘤胃调控剂（戊酸）、3种不同品质的奶牛粗料日粮（分别以苜蓿干草、羊草、玉米秸秆为主的粗饲料日粮）为底物进行体外培养试验,研究了3种不同品质的奶牛粗饲料日粮中分别添加不同浓度的戊酸（1．25mg／g、2．50mg／g、5．00mg／g、10．00mg／g）对其培养液VFA（挥发性脂肪酸）和BCP（菌体蛋白）产量的影响。结果为：①试验组培养液总VFA和BCP各时间点平均值显著高于对照组（P〈0．05）,试验组培养液乙酸、丙酸、丁酸各时间点平均值均高于对照组②在奶牛5种不同品质的粗料日粮中,戊酸对以玉米秸杆为主的粗料日粮体外发酵作用效果最明显;③5种不同品质的粗料日粮中,戊酸的最适添加量均为5．00mg／g．  相似文献   

3.
本试验采用中心组合试验设计对粗饲料来源、可代谢蛋白质(MP)浓度、碳水化合物种类及其互作效应对奶牛养分消化率和生产性能的影响进行了评价。所有日粮(干物质基础)均有50%由苜蓿青贮、玉米青贮构成的粗饲料、10.7%的瘤胃降解蛋白质(RDP)、4.1%~7.1%的瘤胃未降解蛋白质(RUP)、8.8%~12%的MP和22%~30%的淀粉组成。本试验共有15种日粮,试验牛分为6个区组,每个区组6头荷斯坦奶牛,分别进行3个为期21 d的试验。每期按特定顺序饲喂3种日粮后测定试验牛的产奶量、乳成分、采食量及主要营养物质消化率,还考虑了几个主要影响因素间的互作效应。结果表明:日粮淀粉浓度对奶牛养分消化率和生产性能影响较小;用苜蓿青贮代替玉米青贮可降低奶牛的氮消化率、提高中性洗涤纤维(NDF)消化率,还能增加奶牛对日粮干物质(DM)和日粮消化能(DE)摄入量,从而提高能量校正乳(ECM)、乳脂及乳蛋白产量;增加日粮MP浓度可提高奶牛对氮的消化率、ECM和乳蛋白产量,但乳蛋白含量的变化远小于NRC所推荐模型的预测值;DE浓度随淀粉浓度升高呈线性升高,但同时受粗饲料种类和MP浓度互作的影响,即日粮MP浓度较低时,DE浓度会随苜蓿青贮比例升高而降低,而日粮MP浓度较高时,DE浓度会随苜蓿青贮比例升高而升高。  相似文献   

4.
本试验以荷斯坦奶牛为试验动物,用体外批次培养试验法．选择瘤胃调控剂异戊酸（1．25、2．50、5．00、10．00mg／g）,以奶牛3种不同品质的粗饲料日粮（分别以苜蓿干草、羊草、玉米秸秆为主的粗饲料日粮）为底物进行了体外培养试验。主要研究了奶牛3种不同品质的粗饲料日粮中分别添加不同浓度的异戊酸对其培养液VFA和BCP浓度的影响。其结果为：（1）试验组培养液总VFA和BCP各时间点平均值显著高于对照组（P〈0．05）。试验组培养液乙酸、丙酸、丁酸各时间点平均值均高于对照组。（2）在3种不同品质的粗料日粮中,异戊酸对以玉米秸杆为主的粗饲料日粮体外发酵效果作用更明显。（3）在以苜蓿为主的粗饲料日粮中,异戊酸最适添加量为5．00mg／g;在以羊草为主的粗饲料日粮中。异戊酸最适添加量为5．00mg／g：在以玉米秸杆为主的粗饲料日粮中,异戊酸最适添加量为10．00mg/g。  相似文献   

5.
美国的Khorasani等研究用整株大麦／黑小麦或豌豆／黑小麦青贮代替苜蓿青贮饲喂奶牛，观察奶牛采食量、产奶量以及乳成分的变化。该试验用20头泌乳初期的荷斯坦奶牛和24头泌乳中期的荷斯坦奶牛，并分别分为4组，每组饲喂以下4种日粮中的1种，试验持续7周。所有日粮的精粗比均为6：4。蜴干物质计粗料的25％是苜蓿干草，余下的75％是如下成分：①苜蓿青贮；②大麦／黑小麦青贮；  相似文献   

6.
王涛 《中国饲料》2023,1(10):22-25
文章旨在研究全混合日粮（TMR）饲喂技术对奶牛产奶性能及饲料消化率的影响。试验将100头体重相近、健康状况良好，平均干乳期40 d的奶牛随机分为两组，每组5个重复，每个重复10头。对照组奶牛采用精粗分饲的方法，先粗后精，试验组采取全混合日粮饲喂技术，将精饲料和粗饲料充分混合搅拌后饲喂奶牛。预饲期10 d，正试期100 d。结果发现，与对照组相比，试验组奶牛的产奶量在前40 d均无显著变化（P> 0.05），在60～100 d，试验组奶牛的产奶量均显著高于对照组（P <0.05）；试验组奶牛的末重、平均日增重及平均日采食量显著增加（P <0.05），料重比显著降低（P <0.05）；试验组奶牛的干物质、脂肪及能量的表观消化率均显著增加（P <0.05）。总的来讲，相对于传统的精粗分饲的饲喂模式，全混合日粮（TMR）饲喂模式在改善奶牛生长消化及产奶等方面发挥了极大优势，应用推广全混合日粮（TMR）饲喂技术替代传统饲喂技术必将成为我国奶牛集约化养殖的趋势。  相似文献   

7.
文章旨在研究青贮苜蓿对奶牛生产性能、瘤胃发酵及血液生化指标的影响。试验选择年龄、体重、胎次、产奶量相近的泌乳期奶牛30头,随机分为2组,每组3个重复,每个重复5头。其中,对照组饲喂玉米-苜蓿干草型常规日粮,试验组用青贮苜蓿替代苜蓿干草,其他成分不变,试验共计30?d。结果显示：（1）与对照组相比,试验组奶牛总产奶量（TMP）、平均日产奶量（ADMP）显著提高（P＜0.05）|与对照组相比,试验组奶牛料奶比（F/M）显著降低（P＜0.05）。（2）与对照组相比,试验组奶牛pH、氨态氮（AN）显著降低（P＜0.05）|与对照组相比,试验组奶牛挥发性脂肪酸（VFA）、丁酸（BA）显著提高（P＜0.05）。（3）与对照组相比,试验组奶牛血清中总蛋白（TP）、白蛋白（ALB）分别显著提高2.8%、7.4%（P＜0.05）。结论：在奶牛日粮中用青贮苜蓿替代苜蓿干草可以提高奶牛生产性能,改善瘤胃发酵。 [关键词]青贮苜蓿|奶牛|生产性能|瘤胃发酵|血液生化指标  相似文献   

8.
本试验通过给奶牛饲喂不同粗饲料组合的TMR日粮,探讨日粮中不同粗饲料组合对奶牛泌乳性能的影响.结果表明,日粮鲜重的精粗比从30∶70提高到40∶60后,奶牛的干物质采食量有显著地增加（P＜0.05）.随着精料比例增加,其能量水平、蛋白含量和乳蛋白率增加.同时,蛋白含量和产奶量都有所提高.在试验二组中用青贮代替了全贮,提高了奶牛的采食量和泌乳性能.说明,奶牛全混合日粮（TMR）可以提高日粮养分表观消化率、产奶量和改善乳蛋白质水平.青贮饲料的蛋白质的降解和利用更容易被瘤胃微生物降解和吸收,从而提高奶牛的泌乳性能,取得较高的经济效益.  相似文献   

9.
美国的Savoy等就外源性蛋白水解酶对奶牛日粮采食量、纤维消化率、瘤胃发酵和泌乳潜力的影响进行了测定。试验选用8头泌乳初期的荷斯坦奶牛,采用一个双重的4×4拉丁方设计,用2×2因子处理试验进行研究。日粮用大麦青贮和苜蓿干草配制,可维持不同的精粗比(60∶40或36∶44,以干物质计),共分为4组:①不添加外源性蛋白水解酶的高粗料日粮;②添加外源性蛋白水解酶的高粗料日粮;③不添加外源性蛋白水解酶的低粗料日粮;④添加外源性蛋白水解酶的低粗料日粮。所谓外源性蛋白水解酶,即按1.25m L/kg干物质的比率添加在日粮中的制剂,是能够维持蛋白活…  相似文献   

10.
李玉  袁勇  李强  顾慧慧 《中国饲料》2023,1(8):122-125
文章旨在研究不同粗饲料组合对奶牛生产性能、表观消化率及乳品质的影响。试验选取36头体重、胎次、产奶量相近的荷斯坦奶牛,随机分为3组,每组4个重复,每个重复3头。各组均在全混合日粮（TMR）基础上调整粗饲料配比,其中对照组奶牛饲喂100%青贮玉米粗饲料,试验1组奶牛饲喂50%青贮玉米+50%苜蓿干草粗饲料,试验2组奶牛饲喂50%青贮玉米+25%苜蓿干草+25%羊草粗饲料,试验共计60?d。结果显示,（1）试验1、2组奶牛的平均日产奶量（ADMP）比对照组显著提高18.89%、23.13%(P <0.05),且试验1、2组奶牛的料奶比比对照组显著降低15.38%、15.38%(P <0.05)。（2）试验1组干物质（DM）、粗蛋白质（CP）、中性洗涤纤维（NDF）的消化率比对照组显著提高3.85%、4.03%、6.67%(P <0.05),试验2组干物质（DM）、粗蛋白质（CP）、中性洗涤纤维（NDF）的消化率比对照组显著提高5.22%、4.16%、6.71%(P <0.05)。（3）试验1组乳样中乳蛋白率（MPP）比对照组显著提高了3.53%(P <0.05...  相似文献   

11.
Nutrient digestibility, metabolic effects and performance were evaluated in lactating cows (n = 6 × 6) receiving diets containing one of four different lecithins (raw, deoiled and deoiled/partially hydrolysed soy lecithin, raw canola lecithin) or soybean oil in combination with Ca soaps of palm oil fatty acids in a ratio of 1 : 3. A diet supplemented only with Ca soaps served as a control. The complete diets consisted of forage and concentrate (0.62 : 0.38) and total lipid supplementation was 30 g fatty acids/kg dietary dry matter. Lecithins had no effect on milk yield and milk composition. Apparent digestibility of dry matter, organic matter and gross energy were highest in the control diet and lowest in the soybean oil diet (p < 0.1) with intermediate values for the lecithin‐supplemented diets. Soybean oil particularly reduced fibre digestibility (significant with hemicellulose), whereas this effect was reduced or even missing when lecithins, particularly raw canola lecithin and deoiled/hydrolysed soy lecithin, were used. The digestibility of total fatty acids was not affected by the treatments. The effects were also not significant for blood plasma traits except for insulin which was significantly higher with raw than with deoiled/hydrolysed soy lecithin. In conclusion, lecithins, particularly those technologically modified or of a low polyenoic fatty acid content, might be preferred to oils when used as an energy source whereas they failed to improve digestibility of rumen‐protected fats.  相似文献   

12.
Abstract

Rumen metabolism, microbial biomass synthesis and microbial long chain fatty acid composition were studied in lactating cows fed at two levels of dry matter intake (L, 8.6 kg DM and H, 12.6 kg DM) with 0, 4 and 6% added tallow at the low feed level (L0, L4 and L6) and 0, 2, 4 and 6% at the high feed level (H0, H2, H4 and H6).

Fibre digestibility was not significantly affected by tallow addition. Increasing tallow level in the diet decreased the total VFA concentration, the ratio of acetic acid to propionic acid and the ammonia concentration in the rumen. Crude fat and fatty acid content in bacterial and protozoal dry matter increased with increased tallow level, especially due to an increase in fatty acids originating from the feeds. Microbial synthesis in the rumen and flow of amino acids to the duodenum was highest for medium fat intake at the high feed level.  相似文献   

13.
选用4头装有永久性瘤胃瘘管的初产奶牛采用4×4拉丁方设计，研究不添加油脂（CK）、添加4％豆油（LOC1）、4％胡麻油（LOC2）以及2％豆油+2％胡麻油（LOC3）对DM、OM、NDF、ADF瘤胃表观消化率及全肠道消化率的影响。结果表明：在60%高粗料日粮基础上添加4%豆油、亚麻油或二者的混合物，对奶牛干物质采食量没有影响。与对照组相比,添加油组DM、OM、NDF、ADF的瘤胃表观消化率和全肠道消化率都有降低的趋势，但差异不显著（P＞0.05），3个添加油组之间差异也不显著（P＞0.05）。  相似文献   

14.
Twelve multiparous Holstein dairy cows were used in a replicated 4 × 4 Latin square changeover design to evaluate the effects of graded inclusion of soya bean hulls (SHs) in replacement of diet forages at 0%, 10%, 20% and 30% of dietary dry matter (DM) basis on peNDF > 8 and peNDF > 1.18 contents of diets and their resulting effects on chewing activity, nutrient digestibility and milk production of dairy cattle. The control diet contained 50% forage, 50% concentrate and no SH. In the other three diets, SH was substituted for alfalfa hay, corn silage and wheat bran to supply 10%, 20% and 30% of the dietary DM. Increasing SH concentration in the diets resulted in decreasing concentrations of forage neutral detergent fibre (NDF), physically effective NDF (peNDF) and mean particle size (p < 0.01). Chewing activity per kilogram of daily dry matter intake (DMI) was not affected by the different diets tested. However, chewing activity significantly decreased for kilogram intake of NDF, but increased for peNDF > 1.18 when SH was included in the diets (p < 0.01). Total tract apparent digestibility of nutrients significantly increased for DM, organic matter (p < 0.05) and NDF (p < 0.01) but decreased for crude protein (p < 0.05) as the proportion of SH was increased in the diets. Rumen pH value of cattle was not influenced by the diets. Including medium and high amounts of SH in the diets decreased DMI of the animals (p < 0.05) without any significant effect on their daily milk or 4% fat‐corrected milk production. In conclusion, the results of this study showed that the NDF from a non‐forage fibre source like SH had a lower potential for stimulating chewing activity than did forage NDF. Despite this, the small size of dietary particles increased not only the chewing activity per kilogram of peNDF intake but also saliva secretion as well as the potential for rumen to neutralize acids. The findings of this study demonstrate the greater differences in peNDF > 8 among the diets and that these differences are better reflected in terms of DMI, chewing activity and nutrient digestibility, but not in rumen pH.  相似文献   

15.
Eight cows were used to evaluate the effects of supplementation of soy sauce oil (SO) or Ca salts of fatty acids (FA) on rumen fermentation and milk production. The control diet (CO) consisted mainly of hay, corn silage and a concentrate. In the experimental diets, 400 g/day per cow of SO or FA (soybean oil and rapeseed oil) was supplemented to the CO diet. Experimental period for the three treatments was 14 days, and milk samples were taken during the last 2 days and rumen sample was taken on the last day. Dry matter intake was not affected by the treatments. The number of rumen protozoa at 0 h increased by SO and FA diets. Total volatile fatty acids at 2 h after feeding of SO diet was decreased compared to CO. The milk composition yield did not differ among treatments, although the percentages of fat and protein were decreased by SO and FA diets. The proportions of C8–C16 fatty acids in milk fat decreased, and those of C18 increased by SO and FA diets. The proportion of cis‐9, trans‐11 conjugated linoleic acid in milk fat by SO and FA diets increased by 120% and 135%, respectively. In spite of the slight suppression of rumen fermentation by SO diet, negative effects on feed intake and milk production were not detected.  相似文献   

16.
文章旨在探讨日粮添加不同油脂原料对肉牛生长性能、养分消化及瘤胃发酵性能的影响。试验选择平均初始体重（296±32.33）kg、带有瘤胃瘘管的肉牛48头,随机分为4组,每组4个重复,每个重复3头。对照组肉牛饲喂不含油脂的日粮,处理组肉牛分别饲喂含有5%棕榈油、亚麻油和包被脂肪的日粮。在为期10周的饲养试验后测定相关指标。结果：对照组与包被脂肪组干物质、有机物和氮摄入量及干物质、有机物表观消化率显著高于棕榈油和亚麻油组（P＜0.05）,而包被脂肪组与亚麻油组粗脂肪摄入量显著高于对照组和棕榈油组（P＜0.05）。对照组粗脂肪表观消化率较其他组分别显著降低31.94%、32.17%和33.56%（P＜0.05）,而亚麻油组中性洗涤纤维表观消化率较其他组分别显著降低18.61%、17.10%和19.68%（P＜0.05）。包被脂肪组瘤胃不饱和脂肪酸流量较对照组和棕榈油组分别显著提高152.26%和240%（P＜0.05）。对照组与包被脂肪组瘤胃氨氮浓度显著高于棕榈油组和亚麻油组（P＜0.05）。结论：包被脂肪降低了脂肪对瘤胃发酵的影响,其对瘤胃饱和脂肪酸流量的影响与亚麻油相似,但棕榈油降低了瘤胃氨氮浓度,不能有效向瘤胃提供不饱和脂肪酸。 [关键词]油脂原料|肉牛|生长性能|养分消化|瘤胃发酵  相似文献   

17.
The effects of corn dried distillers grains with solubles (DDGS) feeding on rumen fermentation and milk production in cows were evaluated using diets high in neutral detergent fiber (NDF, 45.9–46.6%). The control diet (Control) consisted mainly of hay, corn silage and concentrates. In the experimental diets, the concentrates were replaced with DDGS as 10% dry matter (DM) (10%DDGS) and 20% DM (20%DDGS). Eight cows were used for each 14‐day treatment period. Effect of DDGS feeding on DM intake was not significant. Ruminal volatile fatty acids and ammonia‐N at 5 h after feeding of 20%DDGS were decreased compared to Control, whereas protozoal count at 2 h after feeding of 20%DDGS was higher than that of 10%DDGS. Milk yield of cows fed DDGS diets was greater than that of Control, although percentages of milk protein and solids‐not‐fat were decreased by DDGS diets. The proportions of C10:0, C12:0, C14:0 and C16:0 in the milk fat decreased, and those of C18:0, C18:1, C18:2 and cis‐9, trans‐11 conjugated linoleic acid (CLA) increased markedly with elevated DDGS. Increase in trans‐11 C18:1 was observed in the rumen fluid at 5 h after feeding. These findings suggest that DDGS feeding enhanced milk yield, as well as CLA synthesis under a high dietary NDF condition.  相似文献   

18.
试验评估不同水平柑橘渣对奶牛泌乳性能、养分消化及乳成分的影响。将32头泌乳性能一致的奶牛随机分为4个组,每组4个重复,每个重复2头。对照组饲喂粗脂肪水平为3%的日粮,处理组分别饲喂粗脂肪水平为5.5%的日粮同时添加0(T1)、5%(T2)和10%(T3)柑橘渣。结果显示,与对照组相比,处理组奶牛的粗脂肪摄入量、干物质和粗脂肪表观消化率显著提高(P<0.05),T2和T3组奶牛粗蛋白表观消化率显著高于对照组和T1组(P<0.05)。与对照组相比,处理组乳中粗脂肪含量显著降低(P<0.05),总固形物含量显著降低(P<0.05),乳中粗脂肪产量显著降低(P<0.05)。对照组乳中C10∶0脂肪酸含量最高,而T3组乳中C8∶0脂肪酸和单不饱和脂肪酸浓度最高,饱和脂肪酸浓度表现最低。处理组乳中n-3/n-6脂肪酸显著高于对照组(P<0.05)。研究表明,在高脂肪(5.5%粗脂肪)日粮中添加5%或10%柑橘渣可以提高奶牛粗蛋白表观消化率,且对奶牛的泌乳量和乳品质无负面影响。  相似文献   

19.
This experiment was conducted to determine whether increasing the net energy (NEL) of a total mixed ration (TMR) with mainly unsaturated fat from corn distillers dried grains with solubles (DDGS) vs. rumen inert (RI)‐saturated fat has similar impacts on animal performance. The experiment was an incomplete Youden square with three treatments and four 28‐days periods, completed on a large commercial dairy using three early lactation pens each with approximately 380 multiparity cows. The TMR for all treatments was the same, except for 150 g/kg dry matter (DM) of each TMR which contained 90 g/kg high‐protein DDGS (HPDDGS) and 60 g/kg beet pulp (i.e. low‐fat control diet; LFC); 150 g/kg DDGS (i.e. high‐fat diet with unsaturated fat; HFU); or 111 g/kg HPDDGS, 20 g/kg beet pulp and 19 g/kg RI fat (i.e. high‐fat diet with saturated fat; HFS). The DM intake was highest (p < 0.05) for HFU‐fed cows. Milk, fat and true protein yields, as well as milk energy output, were higher (p < 0.01) when cows were fed HFS vs. HFU and LFC diets. Milk true protein concentration was lowest (p < 0.01) for HFS‐fed cows, but milk fat % was lowest (p < 0.01) for HFU and highest (p < 0.01) for HFS‐fed cows. There were numerous differences (p < 0.01) in milk fatty acid levels amongst diets. The increase in body condition score was lowest (p < 0.01) for LFC. Whole tract digestibility of acid detergent fibre was lower (p < 0.01) for LFC vs. HFS cows, and fat digestion was lowest (p < 0.01) for LFC‐fed cows. This DDGS, high in unsaturated fatty acids, was fed at high levels (i.e. 152 g/kg DM) with little impact on animal performance vs. a lower fat control diet, although addition of an RI‐saturated fat to create a diet with a similarly higher fat level resulted in higher animal productivity.  相似文献   

20.
Abstract

Long-chain fatty acid metabolism in the digestive tract was studied in lactating cows fed at two levels of dry matter intake (L, 8.6 kg DM and H, 12.6 kg DM), with 0, 4 and 6% added tallow at low feed level (L0, L4 and L6), and 0, 2, 4 and 6% fat at high feed level (H0, H2, H4 and H6). Mean fatty acid balance from mouth to duodenum was about zero when corrected for endogenous fatty acids from bile. However, regression analysis showed a microbial synthesis of 68 g at zero fatty acid intake, and a trend which indicated declining de novo synthesis of fatty acids with increasing fat level in the diet. As a mean 68% of the unsaturated C18 fatty acids were hydrogenated in the rumen.

Fatty acid and crude fat true digestibilities decreased with increasing fat intakes owing to a decrease in stearic acid (C18:0) digestibility.  相似文献   

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