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作 者:田雨泽[1] 熊本海[2] 庞之洪[2] 罗清尧[2] 窦红[1]
机构地区:[1]天津市奶牛发展中心,天津300384 [2]中国农业科学院北京畜牧兽医研究所,北京100193
出 处:《农业网络信息》2010年第6期24-26,共3页Agriculture Network Information
基 金:天津市科技计划项目(编号07ZCKFNC01600)
摘 要:针对中国荷斯坦奶牛目前尚无系统完整的泌乳曲线模型的现状,以第一泌乳期305天的、产奶量从7000kg-8000 kg的泌乳奶牛为研究对象,分别采用Wood、Gompertz经验模型和Dijkstra机理模型对每月测定并校正后的产奶数据进行模拟。通过SAS非线性参数估计和均方误差(MSE)分析,筛选得到了三种泌乳产量区间的泌乳曲线模型,包括模型参数和由参数派生的起始产量(y0)、达到泌乳高峰时的天数(tm)、高峰产量(ym)和泌乳持续力(r(th))等泌乳特性指标。上述泌乳曲线模型的建立为准确预测奶牛营养需要、实施奶牛的精细饲养提供了依据。In order to predict precisely nutrient requirements of individual dairy cattle and study lactating characteristics of milk compositions,305-day milk yield data based on 7000kg-7999kg range in the first parity from 49 dairy cows were used.The adjusted month-milk-yields were fitted using 3 equations(Wood,Gompertz and Dijkstra equations),and 3 sets of lactation curve models were obtained by SAS nonlinear parameter estimation and mean square error(MSE) analysis and lactation feature indices of each yield range including initial yield(y^0),time to peak yield(tm),peak yield(ym) and relative rate of decline at the point halfway between peak yield and end of lactation(r(th)) were revealed by model parameters.Above lactation curve models for different lactation ranges could provide reference for the accurate prediction of nutrient requirements and precise feeding for dairy cattle.
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