检索规则说明:AND代表“并且”;OR代表“或者”;NOT代表“不包含”;(注意必须大写,运算符两边需空一格)
检 索 范 例 :范例一: (K=图书馆学 OR K=情报学) AND A=范并思 范例二:J=计算机应用与软件 AND (U=C++ OR U=Basic) NOT M=Visual
机构地区:[1]中国农科院研究生院 [2]中国农科院畜牧研究所 [3]北京市奶牛研究所
出 处:《畜牧兽医学报》1993年第2期136-142,共7页ACTA VETERINARIA ET ZOOTECHNICA SINICA
摘 要:本文采用Wood、改进多项式、回归模型各参数估值及拟合、预报奶量进行了方差分析,遗传力、遗传相关估计及BLUP法育种值估计。方差分析结果表明,产犊季节和胎次对各性状具有较为显著的影响。各遗传相关的估值均较高,这是由环境因素及取样情况所致。实际及估计305天产奶量的遗传力估值较高,Wood模型参数c、改进多项式模型参数d及回归模型参数d、e的遗传力估值也相对较高。各估计、预报奶量及各选定模型参数的BLUP育种值排队序号与实际305天产奶量BLUP育种值排队序号均呈极显著的秩相关(p<0.001).这表明可以用估计和预报奶量及模型参数来评定种公牛的优劣。这对奶牛生产和育种实践具有一定的实践意义。Every 10-day, every 30-day and every 60-day milk yields of 434 Holstein cows from 26 sires were used to derive parameters of the lactation curves using Wood model, modified polynomial model and regression model. The results of analysis of variance for lactation curve parameters and 305-d milk yield showed that the effects of calving season and parity on these traits were significant. The genetic correlations between these parameters (in every model), 305-d milk yield and estimation of 305-d milk yield were very high. This may attribute to the effects of environment and sampling. Heritability estimates were c (in Wood model) :0.141; d (in modified polynomial model):0.362; d, e (in regression model) :0.431, 0.389. Genetic control of these parameters suggested that there was a basis for selection of lactation curves with desired shapes, which could produce higher milk production. The maximum likehood solution gaves the estimators of sire BLUP (Best Linear Unbiased Prediction) breeding values. Ranks of 26 sires for several indices, which include estimation of 305-d milk yield, prediction of 305-d milk yield, b (in Wood model), d (in modfied polynomial model), d (in regression model), d (in prediction model), were compared with their ranks on 305-d milk yield alone by rank correlations. The results of comparison showed that all of the rank correlations were very significant (P<0.001) Selection on these indices resulted in nearly as much gain of 305-d milk yield as selecting for milk alone. Therefore, these indices would be very useful on sire evaluation.
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在载入数据...
正在链接到云南高校图书馆文献保障联盟下载...
云南高校图书馆联盟文献共享服务平台 版权所有©
您的IP:216.73.216.15