不同精料蛋白质水平和不同精料水平对越南当地育肥养牛的影响

发布时间：2021-10-02 04:20

　　本论文的总体目标是评估不同精料的粗蛋白（CP）水平和日粮中的精料水平对越南当地育肥牛的影响。本论文开展了四个试验对此进行研究。试验一主要从农业资源、饲料来源、采食量、日粮结构和日增重五个部分探讨了饲喂系统对越南中部小型农户家中的育肥牛的影响。从越南中部的四个省随机选择了40家农户用于牛整个育肥期数据的采集。结果表明,100%的农户都至少使用了两种精料,超过65%的农户使用了象草或本地野生牧草。精料主要包括米糠、玉米、木薯粉和大米；粗饲料主要包括稻草、本地野生牧草和象草。干物质（DM）摄入量为5.54-5.89千克/天；日粮种的精料比例为24.0%-37.0%；日粮粗蛋白水平为8.37%-9.83%；平均日增重为0.43-0.69千克/天。由此可见,小型农户家中育肥牛的饲料来源是多样的,包括精料和粗饲料；但是,日粮中精料的比例和粗蛋白水平较低。因此,育肥牛的生产性能较低,需要开展进一步的研究,开发含有最佳精料水平和蛋白水平的饲喂模式,提高越南中部小型农户家中育肥牛的生产性能,从而提高经济效益。试验二主要测定了精料中的粗蛋白水平对越南当地育肥牛生产性能、瘤胃内pH值、氨氮浓度、胴体品质、肉... 

【文章来源】：南京农业大学江苏省 211工程院校 教育部直属院校

【文章页数】：157 页

【学位级别】：博士

【文章目录】：
ACKNOWLEDGEMENTS
ABSTRACT
摘要
List of Abbreviations
CHAPTER 1. General Introduction
CHAPTER 2. Literature Review
    1. Beef cattle production in Vietnam
    2. The digestive system in ruminants
        2.1 The digestion and metabolism of nutrients in the rumen
        2.2 Microbial protein synthesis in the rumen
    3. Response of ruminants to concentrate and protein supplementation
        3.1 Response of ruminants to concentrate supplementation
        3.2 Response of ruminants to protein supplements
CHAPTER 3. A Survey on Feeding System for Fattening Local Cattle at SmallholderFarms in Central Vietnam
    Abstract
    1. Introduction
    2. Materials and methods
    3. Results
        3.1 Farming Resources
        3.2 Feedstuffs fed to cattle for fattening at smallholder in Central Vietnam
        3.3 Feed intake of fattening cattle at smallholder in Central Vietnam
        3.4 The structure of diet (concentrate to roughage ratio) for fattening cattle at smallholder in Central Vietnam
        3.5 Daily weight gain of cattle at smallholder in Central Vietnam
    4. Discussion
    5. Conclusion
CHAPTER 4. Effects of Crude Protein Level in Concentrate on Performance ofVietnamese Fattening Local Cattle
    Abstract
    1. Introduction
    2. Materials and methods
    3. Results
        3.1 Feed intake
        3.2 Nutrient digestibility
        3.3 Nitrogen retention and average weight gain
        3.4 pH and NH_3-N concentration in rumen fluid
    4. Discussion
    5. Conclusion
CHAPTER 5. Effects of Concentrate Level on Performance of Vietnamese FatteningLocal Cattle
    Abstract
    1. Introduction
    2. Materials and methods
    3. Results
        3.1 Feed intake
        3.2 Nutrient digestibility
        3.3 Apparent nitrogen retention
        3.4 Body weight change
        3.5 pH and NH_3-N concentration in rumen fluid
    4. Discussion
    5. Conclusion
CHAPTER 6. Carcass Characteristic and Meat Quality of Vietnamese Local CattleFattened on Diets Containing Different Levels of Crude protein in Concentrate andConcentrate Levels
    Abstract
    1. Introduction
    2. Materials and methods
    3. Results
        3.1 Carcass characteristic
        3.2 Characteristic of Longissimus muscle
        3.3 Different organs weight
    4. Discussion
    5. Conclusion
CHAPTER 7. Effects of Crude Protein Level in Concentrate and Concentrate Level inDiet on In Vitro Fermentation and Gas Production
    Abstract
    1. Introduction
    2. Materials and methods
    3. Results
        3.1 Chemical composition, gas production, and apparent in vitro DM and OM digestibility
        3.2 pH, NH_3-N concentration and microbial CP
        3.3 Volatile fatty acid
    4. Discussion
    5. Conclusion
CHAPTER 8. General Discussion
CHAPTER 9. General Conclusion
Future Recommendations
Literature Cited
List of Publications from thesis



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