奶牛日粮中玉米纤维饲料与羊草组合替代苜蓿干草饲喂效果的研究

发布时间：2018-04-24 00:24

本文选题：奶牛 + 物理特性　；参考：《东北农业大学》2017年博士论文

【摘要】：优质粗饲料资源缺乏是我国奶牛养殖业面临的严峻问题之一,利用纤维性非常规饲料资源,如玉米纤维饲料(DCGF)替代奶牛日粮中苜蓿干草可能会有效缓解粗饲料资源短缺的压力。另一方面,饲料的物理特性作为区别于常规化学成分、瘤胃降解特性、小肠消化率等的一类影响饲料营养价值的营养特性,在科研和生产中常常被忽略。本研究的主要目的是:(1)探究饲料物理特性与化学成分、瘤胃降解特性的相关性,揭示饲料物理特性对饲料营养价值评定的重要性,为饲料营养价值评定提供新思路;(2)比较DCGF与苜蓿干草、羊草在营养成分、物理特性、代谢特性的差异,为合理利用DCGF提供科学依据;(3)分析DCGF与羊草组合替代奶牛日粮中部分苜蓿干草对体外发酵、生产性能、消化代谢、经济效益的影响,从而为DCGF替代苜蓿在奶牛中的应用提供理论依据,为缓解我国苜蓿资源短缺的现状提供新思路。试验1:饲料物理特性与化学成分、瘤胃降解特性相关关系的研究本试验测定13种奶牛常用饲料的物理特性(包括持水率、膨胀性、容积密度、溶解性)、化学成分、瘤胃降解特性,采用SAS9.2软件的PROC CORR模块分析物理特性与化学成分、瘤胃降解参数间的相关关系。结果表明:不同饲料的物理特性、化学成分、瘤胃降解特性变异范围较大。相关性分析结果表明,饲料持水率(WHC)与淀粉、粗蛋白(CP)含量呈负相关(P0.05),但与饲料中性洗涤纤维(NDF)、酸性洗涤纤维(ADF)水平呈显著正相关(P0.01)。饲料膨胀性与淀粉、EE含量呈负相关,但与灰分含量呈正相关。饲料容积密度与NDF(rSpearman=-0.720,P0.0001)、ADF(rSpearman=-0.761,P0.0001)、ADL(rSpearman=-0.727,P0.0001)显著负相关。干物质溶解率(DMSol)与饲料NDF、ADF、ADL水平呈显著负相关,但与CP含量呈显著正相关(rSpearman=0.772,P0.0001)。另外,干物质有效降解率(EDDM)与容积密度(rSpearman=0.336,P=0.037)、DMSol(rSpearman=0.560,P=0.001)呈显著正相关。饲料容积密度与CP瘤胃降解参数均无显著相关,但与NDF潜在可降解部分(DNDF)含量呈显著正相关(rSpearman=0.647,P0.001),DMSol与DM和CP降解速率均呈显著正相关。粗蛋白有效降解率(EDCP)与WHC呈负相关(rSpearman=-0.460,P=0.003),与DMSol呈显著正相关(rSpearman=0.503,P=0.001)。试验2:玉米纤维饲料与苜蓿干草、羊草营养特性的比较研究本试验测定DCGF、苜蓿干草、羊草的常规营养成分,并利用康奈尔净碳水化合物-蛋白质体系(CNCPS)对饲料碳水化合物和蛋白质的组分进行剖分,分别采用尼龙袋法和三步体外法测定饲料的瘤胃降解特性和蛋白质小肠消化特性,并利用NRC(2001)模型对不同饲料的真消化率、能值、代谢蛋白(MP)进行估测,同时比较DCGF与苜蓿干草、羊草在物理特性方面的差异。结果表明:DCGF的CP含量与苜蓿干草差异不显著(P0.05),显著高于羊草(P0.05);DCGF的NDF水平显著高于苜蓿干草,而ADF、ADL水平均显著低于苜蓿干草和羊草(P0.05);DCGF氨基酸组成丰富,蛋氨酸含量高于苜蓿干草和羊草,赖氨酸和总氨基酸含量低于苜蓿干草,高于羊草。CNCPS组分方面,DCGF真蛋白(PB)含量显著低于苜蓿干草(P0.05),不可利用蛋白(PC)显著低于苜蓿干草和羊草(P0.05);DCGF的中速降解碳水化合物(CB1)和慢速降解碳水化合物(CB2)含量显著高于苜蓿干草(P0.05),不可利用碳水化合物(CC)含量最低。DCGF的持水率与苜蓿干草相近,显著低于羊草(P0.05);DCGF的容积密度显著高于苜蓿和羊草(P0.05),苜蓿和羊草的容积密度差异不显著(P0.05);DCGF的DMSol和Ash Sol均显著高于苜蓿干草和羊草(P0.05),羊草的DMSol和Ash Sol最低。尼龙袋法测得DCGF的干物质瘤胃降解部分和有效降解率显著高于苜蓿干草和羊草(P0.05),羊草的瘤胃可降解干物质最低;DCGF的CP可溶解部分显著高于苜蓿干草和羊草(P0.05);与羊草相比,DCGF和苜蓿干草的过瘤胃蛋白(RUP)含量更高。DCGF的瘤胃可降解NDF含量显著高于羊草,苜蓿干草的瘤胃可降解NDF含量最低。DCGF的RUP小肠消化率与苜蓿干草差异不显著(P0.05),显著高于羊草(P0.05);苜蓿干草小肠可消化蛋白(IDP)和总可消化蛋白(TDP)含量显著高于DCGF和羊草(P0.05)。NRC(2001)模型估测得出DCGF的总可消化NDF(td NDF)、维持水平下总可消化养分(TDNm)含量高于苜蓿干草,羊草最低;不同饲料的微生物蛋白(MCP)估测量及各能值水平与TDNm趋势相同;DCGF与苜蓿干草的MP供应量差异不显著(P0.05),但显著高于羊草(P0.05)。试验3:玉米纤维饲料和羊草组合替代苜蓿干草对体外产气特性和瘤胃发酵的影响本试验采用由DCGF和羊草组合替代不同比例苜蓿干草的5种奶牛日粮为体外发酵底物:(1)DCGF比例为0%(0DCGF);(2)DCGF比例为3.0%(3DCGF)(3)DCGF比例为7.0%(7DCGF);(4)DCGF比例为11.0%(11DCGF);(5)DCGF比例为15.0%(15DCGF)。采用奥特奇IFM试验室体外发酵装置连续发酵48 h。结果表明:11DCGF日粮各时间点累计产气量均显著高于其它日粮(P0.05),7DCGF日粮与15DCGF日粮产气量差异不显著(P0.05),均显著高于0DCGF和3DCGF日粮(P0.05);11DCGF日粮慢速发酵部分产气量最大,显著高于其它日粮(P0.05)。与0DCGF日粮相比,11DCGF和15DCGF日粮体外干物质消失率(IVDDM)显著提高(P0.05)。11DCGF和15DCGF组日粮氨态氮(NH3-N)产量最高,0DCGF和3DCGF组日粮NH3-N浓度最低;7DCGF和11DCGF组MCP产量显著高于0DCGF日粮(P0.05)。与0DCGF日粮相比,由DCGF和羊草组合替代部分苜蓿干草后,总挥发性脂肪酸(VFA)及乙酸、丙酸、丁酸产量显著提高(P0.05)。试验4:玉米纤维饲料和羊草组合替代苜蓿干草对奶牛生产性能、营养代谢、经济效益的影响本试验选用健康的3头初产、6头经产荷斯坦奶牛,按照胎次、体重、泌乳天数相近的原则分为三组,采用3×3重复拉丁方设计,每个试验期21天。分别饲喂三种日粮:(1)DCGF比例为0%(0DCGF);(2)DCGF比例为7.0%(7DCGF);(3)DCGF比例为11.0%(11DCGF)。试验日粮等能等氮,由DCGF和羊草替代不同比例的苜蓿干草,精料组成及玉米青贮比例基本不变。试验结果表明:饲喂11DCGF组日粮的奶牛干物质采食量(DMI)高于0DCGF组和7DCGF组,且不同日粮对奶牛产奶量、乳脂率、乳糖浓度没有显著影响(P0.05)。与0DCGF组日粮相比,奶牛饲喂11DCGF组日粮提高了乳蛋白含量。在日粮DM和NDF消化率方面,7DCGF(62.7%、45.6%)和11DCGF(63.1%、47.2%)组显著高于0DCGF组(59.4%、42.3%),而氮的消化率在三组间差异不显著(P0.05)。饲喂11DCGF日粮奶牛瘤胃VFA浓度显著高于0DCGF组(P0.05),与7DCGF组差异不显著(P0.05)。在MCP产量方面,11DCGF组(1985.1 g/d)显著高于0DCGF组(1745.0 g/d),与7DCGF组差异不显著(P0.05)。从饲养成本和效益方面看,与饲喂0DCGF日粮(1.64?/kg)相比,饲喂7DCGF和11DCGF日粮(1.51和1.47?/kg)显著降低公斤奶饲料成本,提高经济收益。综上所述,本研究得出以下结论:(1)不同饲料的物理特性、化学成分、瘤胃降解特性各不相同,饲料的物理特性与营养成分、瘤胃降解参数密切相关。因此,饲料物理特性在营养价值评定及日粮配方制作时可能提供新的信息。(2)DCGF的可利用碳水化合物和可利用粗蛋白含量较高,在代谢能供应方面优于苜蓿干草,代谢蛋白供应量与苜蓿干草相近;在物理特性方面,DCGF的容积密度和溶解度高于苜蓿干草,持水率与苜蓿干草相近,膨胀性和物理有效纤维较低。(3)DCGF和羊草组合替代奶牛日粮中17%苜蓿干草后对奶牛生产性能没有不良影响,明显降低公斤奶饲料成本,提高经济效益。由此可见,利用DCGF和羊草组合可以有效替代奶牛日粮中部分苜蓿干草。
[Abstract]:The lack of high quality roughage is one of the serious problems in the dairy farming industry in China. The use of fibrous non conventional feed resources, such as corn fiber feed (DCGF) instead of alfalfa hay in dairy cattle diet, may effectively relieve the pressure of the shortage of crude feed resources. On the other hand, the physical characteristics of feed are different from conventional chemical components. The nutritional characteristics of gastric degradation and intestinal digestibility, such as the digestive rate of the small intestine, are often ignored in scientific research and production. The main purpose of this study is to explore the physical and chemical composition of the feed, the correlation of the rumen degradation characteristics, and reveal the importance of the feed physical properties to feed nutritional value and to feed the feed camp. (2) compare the difference between DCGF and alfalfa hay, Leymus chinensis, physical characteristics and metabolic characteristics, and provide scientific basis for rational use of DCGF. (3) analysis of the effects of DCGF and Leymus chinensis combination of alfalfa hay on the fermentation, production performance, digestion and metabolism, and economic benefits in the diet of dairy cows, so that DCGF It provides a theoretical basis for the application of Alfalfa in dairy cattle, and provides a new idea for alleviating the current situation of the shortage of Alfalfa Resources in China. Test the physical characteristics and chemical composition of the 1: feed and the relationship of the rumen degradation characteristics to determine the physical characteristics of the 13 kinds of dairy cattle feed (including water holding rate, expansibility, volume density, solubility), The relationship between physical properties, chemical components and rumen degradation parameters was analyzed by the PROC CORR module of SAS9.2 software. The results showed that the physical properties, chemical components and rumen degradation characteristics of different feed were larger. The correlation analysis showed that the water holding rate (WHC) and starch, crude protein (CP) were the results of the correlation analysis. The content was negatively correlated (P0.05), but had significant positive correlation with feed neutral detergent fiber (NDF) and acid washing fiber (ADF) level (P0.01). Feed expansibility was negatively correlated with starch, EE content, but positive correlation with ash content. Feed volume density and NDF (rSpearman= -0.720, P0.0001), ADF (rSpearman=-0.761, P0.0001), ADF (rSpearman=-0.761, P0.0001) 0001) significant negative correlation. The dry matter dissolution rate (DMSol) had a significant negative correlation with the feed NDF, ADF and ADL levels, but had a significant positive correlation with CP content (rSpearman=0.772, P0.0001). In addition, the effective degradation rate of dry matter (EDDM) was significantly positively correlated with the volume density (rSpearman=0.336, P=0.037), DMSol (rSpearman=0.560, etc.). There was no significant correlation between the degradation parameters of the rumen, but there was a significant positive correlation with the potential biodegradable part (DNDF) content of NDF (rSpearman=0.647, P0.001). DMSol was significantly positively correlated with the degradation rate of DM and CP. The effective degradation rate of crude protein (EDCP) was negatively correlated with WHC (rSpearman= -0.460, P=0.003). A comparative study of 2: corn fiber feed and alfalfa hay and the nutritional characteristics of Leymus chinensis was compared. The routine nutrition components of DCGF, alfalfa hay and Leymus chinensis were measured, and the composition of carbohydrates and proteins in feed was divided by Connell net carbohydrate protein system (CNCPS), and the nylon bag method and three step in vitro method were used respectively. NRC (2001) model was used to estimate the true digestibility, energy value and metabolic protein (MP) of different feedstuffs, and the differences in physical characteristics between DCGF and alfalfa hay and Leymus chinensis were compared. The results showed that there was no significant difference between the CP content of DCGF and alfalfa hay (P0.05), which was significantly higher than that of alfalfa hay. The NDF level of DCGF was significantly higher than that of alfalfa hay, while the levels of ADF and ADL were significantly lower than alfalfa hay and Leymus chinensis (P0.05); DCGF amino acid composition was rich, methionine content was higher than alfalfa hay and Leymus chinensis. The content of lysine and total amino acids was lower than Alfalfa hay, and the content of DCGF true protein (PB) was significantly lower than that of Alfalfa.CNCPS component. Alfalfa hay (P0.05), the non available protein (PC) was significantly lower than alfalfa hay and Leymus chinensis (P0.05). The medium speed degradation carbohydrate (CB1) and slow degradation carbohydrate (CB2) content of DCGF were significantly higher than that of Alfalfa (P0.05), and the water holding rate of the lowest.DCGF content of the non available carbohydrate (CC) was similar to that of alfalfa hay, significantly lower than that of Leymus chinensis (P0.). 05): the volume density of DCGF was significantly higher than that of alfalfa and Leymus chinensis (P0.05), and the volume density difference between alfalfa and Leymus chinensis was not significant (P0.05); DMSol and Ash Sol of DCGF were significantly higher than alfalfa hay and Leymus chinensis (P0.05), and DMSol and Ash Sol were the lowest. The nylon bag method was significantly higher than alfalfa dry matter degradation and effective degradation rate. The rumen degradable dry matter of weeds and Leymus chinensis (P0.05) was the lowest, and the soluble part of DCGF CP was significantly higher than alfalfa hay and Leymus chinensis (P0.05). Compared with Leymus chinensis, the ruminal NDF content of DCGF and alfalfa hay was higher than that of Leymus chinensis, and the ruminal NDF content of.DCGF was significantly higher than that of Leymus chinensis, and the rumen degradable NDF content of alfalfa hay was the lowest.DCGF. The digestibility of RUP and alfalfa hay was not significant (P0.05), significantly higher than that of Leymus chinensis (P0.05), and the content of digestive protein (IDP) and total digestible protein (TDP) in alfalfa hay was significantly higher than that of DCGF and P0.05.NRC (2001) model to estimate the total digestible NDF (TD NDF) of DCGF, and the total digestible nutrient content under the maintenance level was higher than that of alfalfa. Hay and Leymus chinensis were the lowest; the measurement of microbial protein (MCP) of different feed and the level of each energy value were the same as that of TDNm; the difference of MP supply between DCGF and alfalfa hay was not significant (P0.05), but significantly higher than that of Leymus chinensis (P0.05). The effects of 3: corn fiber feed and Leymus chinensis combination of alfalfa hay on in vitro gas production and rumen fermentation in vitro The experiment used 5 kinds of dairy cow diets, which were replaced by DCGF and Leymus chinensis for different proportion alfalfa hay: (1) DCGF ratio 0% (0DCGF); (2) DCGF ratio 3% (3DCGF) (3) DCGF ratio 7% (7DCGF); (4) DCGF ratio 11% (11DCGF); (5) DCGF ratio is 15% (15DCGF). Using otter IFM test room in vitro fermentation device continuous The results of 48 h. fermentation showed that the cumulative gas yield at each time point of 11DCGF diet was significantly higher than that of other diets (P0.05), and there was no significant difference in grain yield between 7DCGF diet and 15DCGF (P0.05), which was significantly higher than that of 0DCGF and 3DCGF (P0.05). The maximum gas yield of 11DCGF diet was the largest, significantly higher than that of other diets (P0.05). Compared with the 0DCGF diet, 11 The loss rate of dry matter (IVDDM) in DCGF and 15DCGF diets increased significantly (P0.05) in.11DCGF and 15DCGF groups, with the highest yield of ammonia nitrogen (NH3-N), 0DCGF and 3DCGF was the lowest in the diet, while 7DCGF and 11DCGF groups were significantly higher than those in the diet. The yield of VFA and acetic acid, propionic acid and butyric acid increased significantly (P0.05). The effects of 4: corn fiber feed and Leymus chinensis combination instead of alfalfa hay on the production performance, nutrition metabolism and economic benefits of alfalfa were selected for the experiment, 3 first birth and 6 cows were divided into two kinds: the parity, the weight and the milking days. The three group, using 3 x 3 Latin square design, each trial period 21 days, feeding three kinds of diet, (1) DCGF ratio 0% (0DCGF); (2) DCGF ratio of 7% (7DCGF); (3) DCGF ratio of 11% (11DCGF). Experimental diet and other nitrogen, from DCGF and Leymus Leymus to replace the same proportion of alfalfa hay, semen composition and corn silage ratio basically unchanged. Experimental knot The results showed that the dry matter intake (DMI) of dairy cows fed with 11DCGF group was higher than that of group 0DCGF and 7DCGF, and there was no significant effect on milk yield, milk fat rate and lactose concentration in dairy cows (P0.05). Compared with group 0DCGF, dairy cows fed 11DCGF group increased milk egg white content. The DM and NDF digestibility of diet in diet, 7DCGF (62.7%, 45.6%). And 11DCGF (63.1%, 47.2%) group was significantly higher than group 0DCGF (59.4%, 42.3%), but the difference of nitrogen digestibility between the three groups was not significant (P0.05). The concentration of VFA in the rumen of the cows fed with 11DCGF was significantly higher than that in the 0DCGF group (P0.05), and there was no significant difference between the group of 7DCGF and the 7DCGF group (P0.05). The 11DCGF group (1985.1 g/d) was significantly higher than that of the group (1745) in the output of MCP (1745). The difference was not significant (P0.05). Compared with feeding 0DCGF diet (1.64? /kg), feeding 7DCGF and 11DCGF diet (1.51 and 1.47? /kg) significantly reduced the cost of kilogram milk feed and increased economic benefits. Similarly, the physical properties of feed are closely related to nutritional components and rumen degradation parameters. Therefore, the physical properties of feed may provide new information on nutritional value assessment and diet formulation. (2) the available carbohydrate and available crude protein content of DCGF is higher, and the metabolic energy supply is superior to alfalfa hay and metabolic protein supply. In physical properties, the volume density and solubility of DCGF were higher than alfalfa hay, the water holding rate was similar to alfalfa hay, and the expansibility and physical effective fiber were lower. (3) DCGF and Leymus chinensis combination instead of 17% alfalfa hay in dairy cows had no adverse effects on dairy production performance and significantly reduced the cost of kilogram milk feed. It can be seen that the combination of DCGF and Leymus chinensis can effectively replace some alfalfa hay in dairy cattle diets.

【学位授予单位】：东北农业大学
【学位级别】：博士
【学位授予年份】：2017
【分类号】：S823.5

【参考文献】