摘要
为了从奶牛的初期性状中找到影响头胎305 d产奶量的主要因素,保证早期选种的准确性,加速奶牛育种工作,预测奶牛305 d产奶量,对宁夏地区2004—2013年9年之间出生的10 527头中国荷斯坦奶牛的94 743条测定日记录进行分析,并对头胎初产日龄(x_1),日产奶(x_2),乳脂率(x_3),蛋白率(x_4),体细胞评分(x_5),乳糖率(x_6),高峰奶(x_7),高峰日(x_8)和头胎305 d产奶量(y)进行通径分析。通过逐步回归的方法将x6剔除出回归方程。结果显示:宁夏地区奶牛305 d产奶量的回归方程为,y=-1 392.56+0.17x_1+87.87x_2-75.09x_3+245.14x_4-35.95x_5+175.10x_7+5.99x_8;各自变量对回归方程估测可靠度R^2总贡献分析,x_7对R^2的总贡献率为0.52,居各自变量之首。回归方程的建立为准确预测奶牛营养需要、实施奶牛的精细化饲养提供了依据。
The present study was conducted to find the main factors and early traits of dairy cows which affected 305 days milk yield to establish appropriate regression equation for ensuring the accuracy of the early selection and accelerating the breeding of dairy cattle and predicting 305 days milk yield of cows.The data from 10 527 Chinese Holstein cows born between 2004 to 2013 years and 94 743 daily records in Ningxia area were analysed.The gestational age at first calving（x_1）,daily milk yield（x_2）,milk fat percentage（x_3）,protein percentage（x_4）,somatic cell score（x_5）,lactose percentage（x_6） and peak milk（x_7）,the peak day（x_8） and Ningxia Holstein cows a 305 milk quantity（y） of path analysis were used.By the method of stepwise regression the x_6 removed from the regression equations：y=-1 392.56＋0.17x_11＋87.87x_2-75.09x_3＋245.14x_4-35.95x_5＋ 175.10x_7＋ 5.99x_8.Finally,we establish the regression equation of the dairy cows in Ningxia area 305 days milk yield prediction.The reliability analysis of the total contribution of R2 variables to the regression equation to estimate,x_7 total contribution rate of R2 was 0.52,among all the independent variables on the total contribution of the first R2.Above regression equation could provide reference for the accurate prediction of nutrient requirements and precise feeding for dairy cattle.
出处
《畜牧与兽医》
北大核心
2017年第2期22-27,共6页
Animal Husbandry & Veterinary Medicine
基金
"优质高产奶牛选育"项目(2013NYYZ0501)
关键词
头胎产奶量
通径分析
回归方程
残差
first lactation milk yield
path analysis
regression equation
residuals
