【作者】 吴健豪；

【导师】 曲永利；

【作者基本信息】 黑龙江八一农垦大学 ， 动物营养与饲料科学， 2010， 硕士

【摘要】 本研究应用康奈尔净能量净蛋白质体系的原理和方法对黑龙江省大庆地区15种主要奶牛饲料营养成分进行了分析,探讨了用其评定饲料营养价值的可能性;同时借鉴CNCPS体系的CPM-Dairy 3 version模型对黑龙江省规模化奶牛场日均产奶量分别为20 kg和25 kg奶牛的2种日粮进行评估,从而验证CPM模型对奶牛日粮的评价效果。在此基础上,选择9种不同能氮水平日粮饲喂奶牛,研究奶牛尿中嘌呤衍生物(PD)随不同能氮水平日粮变化的规律,探求一种能够特异性反映日粮营养能氮水平在奶牛体内消化吸收动态变化的代谢相指标,研究其与奶牛日粮营养水平的线性关系。从而为建立一种便捷、有效、可靠的奶牛营养检测新方法奠定理论基础。试验一、大庆地区奶牛常用饲料CNCPS体系营养价值测定。应用CNCPS体系提出的蛋白与碳水化合物的分类方法,对大庆地区15种典型奶牛饲料进行测定。试验结果表明,大庆地区15种奶牛常用饲料CNCPS营养组分中,SCP/CP的比例以大庆地区全株玉米青贮饲料最高(68.74%),来自肇东的DDGS最低(10.63%);ADL/NDF比例则以来自齐齐哈尔的苜蓿最高(19.04%),来自齐齐哈尔的玉米最低(6.31%);蛋白质中真蛋白的含量以来自嫩江地区麦麸最高(92.58%),以来自大庆地区全株玉米青贮最低(26.81%);碳水化合物中不可利用纤维(CC/CHO)比例则以来自齐齐哈尔的苜蓿最高(65.01%),来自齐齐哈尔的玉米最低(1.6%)。通过本实验,验证了CNCPS体系的分析方法能够较全面的反映出饲料的营养价值。试验二、应用CPM模型改善日粮能氮平衡和提高奶牛生产性能的效果评价。选择健康、胎次、体重和泌乳阶段相近的奶牛56头,分成2组,组日均产奶量分别为20和25 kg,按配对试验设计要求把试验奶牛分成对照组和试验组,对照组日粮为奶牛场当前的日粮,试验组日粮为应用CPM软件调整后的日粮。试验期为45 d。通过对比饲养试验检验CPM模型在日粮评价和预测奶牛生产性能方面的应用效果。结果表明,饲喂调整后日粮的奶牛产奶量、4%标准乳产量、乳尿素氮和血浆尿素氮含量均略高于对照组(P>0.05),试验组Ⅰ的乳脂率略高于对照组Ⅰ(P>0.05),二者乳蛋白率相似,试验组Ⅱ的乳脂率、乳蛋白率则略低于对照组Ⅱ(P>0.05);调整后2种日粮成本分别比调整前每天降低2.43元和2.12元。试验还显示,利用CPM模型预测产奶量与实际产奶量的差距除了对照组Ⅰ之外,其他处理组均在6%之内,预测DMI与实际DMI的差距在5%之内。因次,在我国规模化奶牛场应用CPM模型可以起到预测日粮的营养价值、改善日粮的能氮平衡、提高奶牛的生产性能和降低饲养成本的作用。试验三、尿中嘌呤衍生物(PD)同奶牛日粮蛋白质和能量水平的相关分析。选择健康、胎次、体重和泌乳阶段相近的奶牛27头,采用3×3析因试验设计,利用CPM-Dairy 3模型设计的代谢能量、代谢蛋白质分别为需要水平的127%和123%;代谢能量、代谢蛋白质分别为需要水平的75%和80%的日粮,再将这些日粮以上述能氮梯度区间划分为9种不同能氮水平的日粮并分别饲喂各组奶牛,利用全收尿法研究奶牛尿中的嘌呤衍生物(UPD)值随日粮不同能氮水平变化的规律。结果表明,当日粮中代谢蛋白含量处于同一水平时,奶牛尿中嘌呤衍生物的含量随着代谢能量水平升高而增加,而且尿酸(8.24 mmol/d~22.75 mmol/d)、尿囊素(49.61mmol/d~137.10 mmol/d)和总PD(57.85 mmol/d ~159.86 mmol/d)变化规律相同;当日粮中代谢能量处于同一水平时,尿中嘌呤衍生物的含量是随着代谢蛋白水平升高而增加,而且尿酸、尿囊素和总PD含量变化规律相同。通过线性回归分析,发现奶牛尿液中尿酸、尿囊素和总PD含量与日粮中能氮水平变化呈线性关系。从尿酸、尿囊素比例来看,9种日粮中除了饲喂HELP、MELP和LEMP组日粮奶牛尿中尿酸与尿囊素的比值为0.18:0.82和0.19:0.81外,其他各组日粮均为0.14:0.86。更多还原

【Abstract】 In this study, twenty-three typical feed were collected from northeast agricultural region to analyze the chemical composition using CNCPS model and estimate their nutritive value. Meanwhile, two kind of dairy diets (for the cows of 20 and 25 kg milk production) common used in diary farm were evaluated according to the CPM-Dairy 3 version model of CNCPS to find out whether CPM model could be effectively applied in the evaluation and prediction of dairy performance.On the base of this, nine diets with different levels of protein and energy content were fed to the cows and the concentrations of purine derivatives (PD) was determined to investigate if they could reflect the information of protein and energy level in the diet and then to lay the foundations of development of more effective, convenient and reliable method for dairy nutrition measurement.Exp.1 CNCPS for evaluation to feeds of dairy cows in DAQING region.Fifteen typical feedstuff were collected to analyze the chemical composition by CNCPS system proposed classification of protein and carbohydrate. The results showed that SCP/CP was highest in whole-plant corn silage from Daqing City (68.74%) and lowest in DDGS from Zhaodong City(10.63%); And alfalfa from Qiqihaer City had a very high value of ADL/NDF (19.04%) while corn from Qiqihaer City had the weakest value (6.31%). With respect to the true protein and unavailable fiber content, wheat bran from Nenjing City and alfalfa from Qiqihaer City were in the greatest level (92.58% and 32.50%, respectively), as whole-plant corn silage from Daqing City and cornFrom Qiqihaer City had the lowest value (26.81% and 1.6%, respectively). It concluded that the application of CNCPS could be extended in the evaluation of feedstuff of dairy cows in Daqing region of china since it could reflect the comprehensive nutritional ingredients of feedstuff and metabolisms of digestion and absorption in dairy cows.Exp.2 Evaluation for increasing diary cattle performance and improving diet energy nitrogen balance applying CPM model.Fifty-six dairy cows with similar parity, DIM and body weight were selected and divided into two groups according to the milk production (20 kg and 25 kg). Then paired test was conducted in each group. The diet applied in the dairy farm was denoted as the control and the diet adjusted by CPM model was denoted as the treatment. The trial lasted for 45 d. The results showed that, milk yield, 4% fat corrected milk yield, blood urea nitrogen (BUN) and MUN content were slightly higher in the cows fed the adjusted diet than those fed the control (P>0.05). In group I, The milk fat percentage was lower in the cows fed the control (P>0.05), but milk protein percentage was not altered. But in group II, the cows fed adjusted diet had lower content of milk fat and protein (P>0.05). After adjustment, the cost were decreased by $2.43/d and $2.12/d compared with the original diets, respectively. The difference between the predicted and determined value of milk yield and DMI was less than 6% and 5% with the exception of those in the control diet of group I. In conclusion, the CPM model of CNCPS could effectively predict the nutritive value of dairy ration and decrease the feeding cost without any impair in animal performance.Exp.3 Relative analysis of PD in urine with different levels of protein and energy.twenty-seven dairy cows with similar parity, DIM and body weight were selected for 3×3 factorial trial to investigate the regularity of UPD in urine of cows fed different diets using complete urine collection method. The treatments were three levels of metabolism energy supplement in the diet (127%ME/Require ME, 100%ME/Require ME, 75% ME/Require ME) and three levels of metabolism protein (123% MP/Require MP, 100% MP/Require MP, 80% MP/Require MP) by CPM-Dairy 3 version model. The results showed that when the metabolizable protein content was constant, the concentration of UPD was increased with the increasing level of metabolizable energy and the concentrations of uric acid (8.24-22.75 mmol/d) , allantoin(49.61-137.10 mmol/d)and total UPD(57.85-159.86 mmol/d) had similar tendency. When the metabolism energy was at the same level, the content of UPD increased when metabolizable protein level increased. Linear relationships were found between the contents of allantoin, uric acid and total UPD and the protein and energy level in the diets. The ratio of content of allantoin and uric acid was 0.18:0.82 and 0.19:0.81 in the cows consumed HELP, MELP and LEMP diets, and the cows fed others six diets had the ratio of 0.14:0.86.更多还原