高产与低产奶牛的乳成分差异及其对乳能量预测模型的影响  

Difference of Milk Composition in High and Low Yield Dairy Cows and Its Influence on Milk Energy Prediction Model

作　　者：牛慧 童津津 张华 毛胜勇[2] 熊本海[3] 麻柱[4] 蒋林树 NIU Hui;TONG Jinjin;ZHANG Hua;MAO Shengyong;XIONG Benhai;MA Zhu;JIANG Linshu(Beijing Key Laboratory of Dairy Cattle Nutrition,Institute of Animal Science and Technology,Beijing University of Agriculture,Beijing 102206,China;Institute of Animal Science and Technology,Nanjing Agricultural University,Nanjing 210095,China;Beijing Institute of Animal Husbandry and Veterinary Sciences,Chinese Academy of Agricultural Sciences,Beijing 100193,China;Beijing Dairy Cattle Center,Beijing 100085,China)

机构地区：[1]北京农学院动物科学技术学院,奶牛营养学北京市重点实验室,北京102206 [2]南京农业大学动物科技学院,南京210095 [3]中国农业科学院北京畜牧兽医研究所,北京100193 [4]北京奶牛中心,北京100085

出　　处：《动物营养学报》2020年第7期3214-3223,共10页CHINESE JOURNAL OF ANIMAL NUTRITION

基　　金：“十三五”国家重大科技专项(2016YFD0700201,2016YFD0700205,2017YFD0701604);北京市现代农业产业技术体系奶牛创新团队;国家自然科学基金项目(31802091,31702302,31772629)。

摘　　要：本研究以北京市某奶牛养殖场(2016—2019年度1~4胎)奶牛的生产性能测定(DHI)数据为基础,分析了185头高产奶牛和158头低产奶牛的生产性能,旨在通过分析产奶量与乳成分的相关性,探究高产与低产奶牛的乳成分差异;同时,根据中国《奶牛饲养标准》建议计算乳能量,探究高产与低产奶牛乳能量随泌乳时间的拟合曲线,建立高产与低产奶牛在不同泌乳阶段的乳能量预测模型。结果表明:高产与低产奶牛的乳脂率、乳蛋白率、乳体细胞数存在极显著差异(P<0.01),乳脂率、乳蛋白率、乳体细胞数与产奶量呈显著负相关(r=-0.851、r=-0.654、r=-0.811,P<0.01)。高产与低产奶牛的乳能量随泌乳时间的延长均呈现出先下降后上升的趋势,拐点在泌乳60 d左右。根据产奶量分别构建高产与低产奶牛在泌乳前60 d和泌乳60 d之后的乳能量预测模型,对于高产奶牛,泌乳前60 d的最优模型为E=4.573-0.031X(R^2=0.918,残差范围:-0.9578~1.4327,P<0.01,n=7400)(式中:E为乳能量;X为产奶量。下同),泌乳60 d之后的最优模型为E=3.890-0.019X(R^2=0.980,残差范围:-0.9680~1.5906,P<0.01,n=7400);对于低产奶牛,泌乳前60 d的最优模型为E=4.280-0.038X(R^2=0.958,残差范围:-0.9593~1.4573,P<0.01,n=6320),泌乳60 d之后的最优模型为:E=4.178-0.034X(R^2=0.887,残差范围:-1.1976~1.5895,P<0.01,n=6320)。本研究分析了高产与低产奶牛的乳成分存在差异,得出高产奶牛的乳脂率、乳蛋白率和乳体细胞数极显著低于低产奶牛;此外,本研究还建立了不同泌乳阶段高产与低产奶牛的乳能量预测模型,可对奶牛的泌乳净能需要进行预测,以便奶牛场调整饲料结构,达到奶牛的最佳生产状态。Based on dairy herd improvement(DHI)data of dairy cows from a dairy farm in Beijing(1 to 4 parities in 2016—2019),this study analyzed the performance of 185 high yield dairy cows and 158 low yield dairy cows,aiming to explore the difference of milk composition between high and low yield dairy cows by analyzing the correlation between milk yield and milk composition.At the same time,milk energy was calculated according to the suggestion of Dairy Cattle Feeding Standard,the fitting curves of milk energy of high and low yield dairy cows with lactation time were explored,and the milk energy prediction models of high and low yield dairy cows at different lactation periods were established.The results showed that there were significant differences in milk fat percentage,milk protein percentage and milk somatic cell count(SCC)between high and low yield dairy cows(P<0.01).There was a significant negative correlation between milk fat percentage,milk protein percentage,milk SCC and milk yield(r=-0.851,r=-0.654,r=-0.811,P<0.01).The milk energy of high and low yield dairy cows decreased firstly and then increased with lactation time,and the turning point was about at 60 days of lactation.According to the milk yield,the milk energy prediction models of high and low yield dairy cows were constructed respectively before and after 60 days of lactation.For high yield dairy cows,the optimal milk energy model before 60 days of lactation was E=4.573-0.031 X(R^2=0.918,residual range:-0.9578 to 1.4327,P<0.01,n=7400)(in the formula,E mean milk energy and X mean milk yield,the same as below),and the optimal milk energy model after 60 days of lactation was E=3.890-0.019 X(R^2=0.980,residual range:-0.9680 to 1.5906,P<0.01,n=7400).For low yield dairy cows,the optimal milk energy model before 60 days of lactation was E=4.280-0.038 X(R^2=0.958,residual range:-0.9593 to 1.4573,P<0.01,n=6320),and the optimal milk energy model after 60 days of lactation was E=4.178-0.034 X(R^2=0.887,residual range:-1.1976 to 1.5895,P<0.01,n=6320).This study a

关 键 词：高产奶牛 低产奶牛 乳成分 产奶量 乳能量 预测模型 

分 类 号：S816[农业科学—饲料科学]