毕业论文---奶牛的乳成分与产奶量的相关分析.doc

目录1 引言 2 1 材料与方法 2 1.1 实验材料 2 1.2 方法 3 1.2.1 产奶量的记录方式 3 1.2.2 乳成分的分析 3 1.2.3 产奶量记录及数据的统计 3 1.3 统计分析方法 3 1.3.1相关系数、通经系数的计算 3 1.3.2 自变量对依变量的作用剖分和决定程度的分析 3 2 结果与分析 3 2.1 奶牛乳成份和产奶量的表型参数 3 2.2 性状间的相关分析 4 2.3 通径分析 5 2.4 相关系数的剖分 5 2.5 决定程度分析 6 3 讨论 7 3.1 产奶量的主要影响因素。 7 3.2 多元相关分析自变量的确定。 7 3.3 乳成分影响产奶量的决定程度分析结果。 7 4 结论 7 参考文献 8 致 谢 9 奶牛的乳成分与产奶量的相关分析 本科生: 郭静 指导老师: 刘小林教授 (西北农林科技大学动物科学院动物科学,陕西杨凌 712100 摘 要：随着人们生活水平的提高，人们对乳成分的要求越来越高，因此在提高产奶量的同时如何保证并提高乳成分显得越来越重要。因此了解产奶量与乳成分之间关系显得至关重要。本研究以西安市草滩第五奶牛场选取的健康、泌乳正常的第2泌乳期奶牛为研究对象，随机抽取150头奶牛，测定其乳成分和产奶量之间的关系，采用相关分析的方法确定其乳成分和305d产奶量之间的关系，以各项乳成分为自变量，305d产奶量为依变量进行相关分析。结果表明，乳蛋白与月产奶量间存在极显著的相关性（P0.01），体细胞数与月产奶量间存在显著的相关性（P0.05），而乳脂率与月产奶量之间无显著相关（P0.05）；乳蛋白与乳脂率与校正后的305天产量间均存在极显著的相关性（P0.01）。说明了乳蛋白、乳脂率及体细胞数是影响产奶量的主要因素。 [关键词]：奶牛；乳成分；产奶量；相关分析 Correlation analysis between milk composition and milk yield in dairy cattle Graduate: Guo Jing Supervisor: Liu Xiao-Lin (College of Animal Science Technology, Northwest AF University, YangLing, Shanxi, 712100) Abstract：As people’s living standard improved, their requirements of milk composition are becoming higher and higher, so how to ensure and improve milk composition while raising milk production become increasingly important, so raises the importance of understanding the relationship between milk yield and milk composition. This research chooses the healthy dairy cattle with normal lactation in their second period, selected by the Xi’an Mash to the Fifth Dairy Farm for study. In the research, we selected 150 dairy cattle by random and evaluated the relationship between its milk production and milk composition firstly. Secondly, we adopted the correlation analysis; take the milk composition as variables, 305 d milk production as in variable, to measure the relationship between its milk composition and 305 d milk production. The conclusion shows that milk protein has significant correlation with monthly milk production （P0.01）, and somatic cell count also has significant correla