NEW CONCEPTS OF SIRE AND COW EVALUATION T O INCREASE GENETIC PROGRESSIN CATTLE

New developments in sire evaluations have been discussed in recent yea rs: test-day modells (TDM) allow a better controll of direct environme ntal effects on the herd and a prediction of lactation results. One ad vantage is to avoid an adjustment for days in milk with older extensio n factors, but the calculation and application of factors within the e valuation system. TDM also allow more flexibility with regard to test- day intervalls and changing testing methods. Effects on the possible s election progress are to be expected through an increase in the proofs with the inclusion of all available test-day records for all cows, wh ich could also result in a decrease of the generation intervall. These advantages can only be used, if the evaluations are conducted more fr equently (at least in quarterly intervalls), which is technically appl icable and desirable for an increased selection progress.