Zeitabhängige genetische Effekte bei Milchkühen

Food and resource shortages pose a serious global challenge for science to search for and improved food production under simultaneous consideration of resource preservation. The introduction of genomic selection appears to be promising to directly breed for genetic dispositions without the knowledge of the complex network of causative genes. Nevertheless, a significant association with genetic markers is also the basis of genomic selection. To date, such associations were assessed based on static 305-day breeding values or averaged yield deviations. However, many quantitative traits such as lactation yields show a phenotypical time-dependency, and dynamic gene expression studies also show a variable influence on individual lactation periods. Animal health and fertility as well as economic aspects could be improved in the first third of the lactation through changing individual lactation periods, e.g. a lower maximum production with an increased persistency. Preliminary association studies showed methods and results which could enable us to incorporate time-dependent variability in genomic selection (Strucken et al. 2011 & 2012). The aim of this study is to test and extend current methods and results for dynamic genetic association studies.