EPD估计的原理与应用

EPD是在BLUP理论的基础上对种用动物遗传值估计的一种参数。EPD值是估计育种值的一半，它是一个容易理解和应用的种畜遗传传递力的值，能很直观地反映种畜价值在其后代中的体现。EPD主要是用在同一品种中2个不同个体间直接遗传效应的比较，从而预测在同一平均遗传值水平上种用动物未来子女的性能差异。EPD适用于动物的出生、发育、母性性状、屠宰性状以及其它特征性状的估计。EPD广泛应用于肉用种公牛价值的评定。对肉牛重要经济性状EPD估计后，以出版物和（或）计算机网络的方式发布，肉牛生产者根据自己的不同需要选用种牛或精液。作者对EPD的估计原理与应用作较为详细的论述。

The Principles and Applications Of EPD Estimated

Expected progeny difference(EPD) is a sort parameter which provides estimation of the genetic value of an animal as a parent based on theory of BLUP.EPD value is a half of estimated breeding value,which is understood easily.It directly reflects breeding value from animal.Specifically,EPD is main index for genetic merit differences between two individuals from the same breed.So it can predict performance differences between their offspring if they are mated to animals having average genetic merit.EPDs are calculated for birth,growth,maternal,and carcass traits and more traits with animal performances.EPD has been broadly applied in sire evaluation.The results of EPD estimation for individual are easily been published or announced on internet and(or) intranet.The producer can select their favorite bulls according to their own requirements.The paper will give details about the principles and applications of EPD.