Study on the integration of dry matter intake of young bulls as additionalselection trait in artificial insemination breeding programs for dairy cattle - 1st communication: Estimation of genetic parameters

Aim of this study was to estimate genetic parameters for traits recorded in the performance test of potential bulls for the artificial insemination in the breed German Holsteins. The estimation of the genetic parameters was b ased on data recorded in the test station "Anstalt fur Leistungsprufungen i n der Tierzucht" in Eickelborn. The performance test data of 520 "German Ho lstein" bulls performance tested between 1992 and 1996 were analysed. The a nalysis was focused on the dry matter intake and it's correlation to other performance traits. The estimated heritability and the additive genetic sta ndard deviation for the daily dry matter intake during test period was 021 and 180 g/day. This genetic foundation seems to be sufficiently high to obt ain a satisfactory selection progress. First results indicate, that the cor relation between daily dry matter intake and daily weight gain is genetical ly favourable whereas the correlation between daily dry matter intake and e nergy efficiency is unfavourable. Exterior traits of bulls are presumable not suitable for selection on daily dry matter intake. Moreover the suitability of linear exterior traits of c ows for improving the dry matter intake should be investigated.