不同泌乳阶段和体细胞水平的中国荷斯坦奶牛泌乳性能差异和相关性研究  

Differences and Correlations of Lactation Performance in Chinese Holstein Dairy Cows at Different Lactation Stages and Somatic Levels

作　　者：余诗强 李留学 赵小博 赵慧颖 屠焰[2] 赵玉超 蒋林树 YU Shiqiang;LI Liuxue;ZHAO Xiaobo;ZHAO Huiying;TU Yan;ZHAO Yuchao;JIANG Linshu(Beijing Key Laboratory of Dairy Cow Nutrition,Animal Science and Technology College,Beijing University of Agriculture,Beijing 102206,China;Feed Research Institute,Chinese Academy of Agricultural Sciences,Beijing 100081,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]中国农业科学院饲料研究所,北京100081

出　　处：《畜牧兽医学报》2023年第3期1003-1014,共12页ACTA VETERINARIA ET ZOOTECHNICA SINICA

基　　金：北京市教育委员会重点项目(KZ202010020029);北京农学院科技创新“火花行动”支持计划(BUA-HHXD2022011)。

摘　　要：旨在通过数据分析不同泌乳阶段和体细胞水平的中国荷斯坦奶牛泌乳性能差异、相关性和变化规律,为不同泌乳阶段奶牛的饲养管理、控制乳体细胞数(SCC)及改善乳品质提供理论依据。本研究基于北京14家奶牛场,选取健康正常泌乳生产的奶牛,共得到285045条生产性能测定报告(dairy herd improvement,DHI),按0~99 d、100~199 d、200~299 d和300 d以上(含300 d)分为4个泌乳阶段,按低SCC组(0~20万个·mL^(-1))、中SCC组(20~50万个·mL^(-1))、高SCC组(50万个·mL^(-1)以上)分为3个水平,将原数据经过预处理后获得251949条DHI报告,采用Duncan多重比较和Pearson相关性分析等方法进行分析。结果表明:1)不同泌乳阶段奶牛的产奶量、乳脂率、乳蛋白率、脂蛋比、乳糖率、尿素氮(MUN)和SCC存在显著性差异(P<0.01),不同泌乳阶段奶牛产奶量与乳脂率、乳蛋白率、SCC均呈显著负相关,与乳糖率均呈显著正相关,乳脂率与乳蛋白率呈显著正相关(P<0.01)。2)不同SCC水平奶牛泌乳天数、产奶量、乳脂率、乳蛋白率、脂蛋比和乳糖率存在显著性差异(P<0.01),奶牛在低SCC水平和高SCC水平中产奶量与SCC表现为显著正相关(P<0.01),中SCC水平表现为显著负相关(P<0.01),不同SCC水平上产奶量均与乳脂率、乳蛋白率呈显著负相关(P<0.01),与乳糖率呈显著正相关(P<0.01)。3)产奶量随泌乳天数的变化曲线为:y=-3×10^(-9)x^(4)+3×10^(-6)x^(3)-1.5×10^(-3)x^(2)+2.039×10^(-1)x+34.437(R^(2)=0.9759);乳糖率随泌乳天数的变化曲线为y=-1×10^(-15)x^(6)+2×10^(-12)x^(5)-2×10^(-9)x^(4)+6×10-7x^(3)-1×10^(-4)x^(2)+8.4×10^(-3)x+4.9992(R^(2)=0.9847);SCC随泌乳天数的变化曲线为:y=-4×10^(-12)x^(5)+6×10^(-9)x^(4)-3×10^(-6)x^(3)+8×10^(-4)x^(2)-8.89×10^(-2)x+22.862(R^(2)=0.7829);乳蛋白率随泌乳天数的变化曲线为:y=4×10^(-15)x^(6)-7×10^(-12)x^(5)+5×10^(-9)x^(4)-2×10^(-6)x^(3)+3×10^(-4)x^(2)-1.94×10^(-2)x+3.576(R^(2)=0.9437);乳脂率随泌�The study aimed to analyze the differences,correlations and changing rules of lactating performance of Chinese Holstein cows at different lactation periods and somatic cell levels by data analysis,so as to provide a theoretical basis for the feeding and management of dairy cows at different lactation periods,the control of milk somatic cell count and the improvement of milk quality.Based on a total of 285045 production performance measurement reports(DHI,Dairy Herd Improvement)from 14 dairy farms in Beijing,selecting healthy and normal lactating cows,4 lactation stages were divided according to 0-99 d,100-199 d,200-299 d and more than 300 d(including 300 d),the low SCC group(0-20×10^(4)·mL^(-1)),medium SCC group(20×10^(4)·mL^(-1)-50×10^(4)·mL^(-1)),high SCC group(more than 50×10^(4)·mL^(-1))were divided.A total of 251949 DHI reports were obtained from the raw data after pretreatment,and were analyzed by Duncan multiple comparison and Pearson correlation analysis.The results showed that:1)There were significant differences in milk yield,milk fat percentage,milk protein percentage,F/P,lactose percentage,MUN and SCC of dairy cows in different lactation periods(P<0.01).Milk yield in different lactation periods had a significant negative correlation with milk fat percentage,milk protein percentage and SCC,and a significant positive correlation with lactose percentage,and a significant positive correlation between milk protein percentage and milk fat percentage(P<0.01).2)There were significant differences in the days of lactation,milk yield,milk fat percentage,milk protein percentage,F/P and lactose percentage of dairy cows with different levels of SCC(P<0.01).The milk yield of dairy cows at low and high levels of SCC was significantly positively correlated with SCC(P<0.01),and the medium level of SCC was significantly negatively correlated(P<0.01).The milk yield at different levels of SCC was significantly negatively correlated with milk fat percentage and milk protein percentage(P<0.01),and significantly posi

关 键 词：奶牛 泌乳阶段 体细胞水平 乳成分 相关性 变化规律 

分 类 号：S823.2[农业科学—畜牧学]