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作 者:毛永江[1] 张亚琴[1] 许兆君[1] 刘姗[1] 张美荣[1] 常玲玲[1] 杨章平[1]
机构地区:[1]扬州大学动物科学与技术学院,扬州225009
出 处:《畜牧兽医学报》2011年第9期1239-1248,共10页ACTA VETERINARIA ET ZOOTECHNICA SINICA
基 金:国家高新技术研究发展计划(863)项目(2008AA10Z144);国家科技支撑计划(2008BADB2B03-06);江苏省高校自然科学基础研究项目(08KJB230005);江苏省高校自然科学研究重点项目(09KJA230002)
摘 要:为了解南方大型奶牛场中国荷斯坦牛泌乳曲线及其影响因素,利用5种泌乳曲线模型(Wood模型、Nelder逆多项式模型、WIL模型、混合对数模型和Ali-Schaeffer模型)和4种时间间隔方式(天、周、旬和泌乳月),对海丰奶牛场2009-2010年度980头第1~5胎具有完整泌乳期的中国荷斯坦牛296 895次日产奶量记录进行泌乳曲线拟合,并进一步分析不同模型、时间间隔和胎次3个因素对泌乳曲线拟合度及其参数的影响。结果表明,5种模型泌乳曲线拟合度变化范围为0.839 7~0.954 1,不同模型和胎次极显著影响泌乳曲线拟合度(P<0.01),时间间隔对泌乳曲线拟合度无显著影响(P>0.05)。Ali-Schaeffer模型拟合度最高,Nelder逆多项式模型拟合度最低;不论哪种泌乳曲线模型,第一胎拟合度均显著高于第三胎。不同模型、时间间隔和胎次均极显著影响参数a值(P<0.01),模型极显著影响参数b值(P<0.01),时间间隔显著影响参数b值(P<0.05)。模型和胎次均极显著影响高峰产奶量和产奶高峰日(P<0.01)。综合各方面情况,确定Ali-Schaeffer模型为适合于海丰奶牛场奶牛的最佳泌乳曲线模型。The objective of this study was to reveal the lactation curve and the influencing factors for large dairy cattle farm in south of China.The lactation curve was fitted by 5 mathematical models(including the wood's incomplete gamma function model,Nelder inverse quadratic polynomial model,Wilmink model,mixed log model and Ali-Schaffer model) and 4 time interval(including daily,weekly,ten days and milking monthly) on 296 895 daily milk yield records of 980 Chinese Holstein with all first lactation to fifth lactation from year 2009 to 2010 in Haifeng Dairy Farm.The effects of models,time interval and parity on fitness and parameter of lactation curve were analyzed by ANOVA.The results showed that the fitness of 5 lactation curve models ranged from 0.839 7 to 0.954 1.The models and parity showed significant effect on the fitness of lactation curve at P0.01,and the time interval showed no significant effect on the fitness of lactation curve.By the fitness of lactation curve,the Ali-Schaeffer was largest,and the Nelder inverse quadratic polynomial model was least.The fitness of lactation curve for the first lactation was higher than that of the third lactation for all models.The a value of lactation curve was affected significantly by models,time interval and parity at P0.01 level.The b value of lactation curve was affected significantly by models at P0.01 level,and by time interval at P0.05 level.The peak milk yield and the day in peak milk yield were affected significantly by the models and parity at P0.01 level.The result indicate that the Ali-Schaeffer model is the best model to fit the lactation curve for Haifeng Dairy Farm based on all information in this study.
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