Calculating cow and daughter yield deviations and partitioning of genetic evaluations under a random regression model

摘要: Abstract The equations for calculating cow yield deviations (YD) and partitioning genetic evaluations when using a random regression model (RRM) were presented. Calculations illustrated results from RRM the evaluation of test day (TD) somatic cell count (SCC) in first three lactations 1,287,930 Holstein/Friesian heifers. Random regressions animal partitioned into contributions parent average, YD progeny. These vectors progeny are regressions, therefore relative contribution these different sources information can be computed any milk. computing daughter (DYD) bulls presented RRM. For with almost 50 daughters, correlation between DYDs was 0.77 compared 0.48 an (AM). higher may reflect better correction environmental factors increased to 0.97 0.96 AM 51–99 daughters. However, 200 daughters or more, correlations 0.99 both models.