This study was carried out for the aim of solving the selection response on nucleus herds in dairy cattle by using the Multiple Ovulation Embryo Transfer(MOET), coupled with adapting In Vitro Embryo Production(IVEP), and settled down the nine kinds of hierachical mating plans according to the number of sires and dams, and did simulation for breeding schemes and IVEP levels. The results obtained were as follows ;
1. The annual rate of inbreeding coefficients were decreased according to increasing the number of sires and dams. It was low in the mating plan with many sires and dams, when the mating ratios of dam to sire are equal. These trends were similar to the juvenile, adult and progeny testing schemes.
2. The annual rate of selection response was high as increasing IVEP levels and the number of sires and dams.
3. The annual rate of selection response was the highest in the case of adult scheme and was the lowest in the case of progeny test scheme, regardless of mating plans and IVEP levels.
4. The rate of selection responses in the low IVEP level with many sires and dams were similar to those in the high IVEP level with few sires and dams, so if we would increase IVEP levels, the number of sires and dams and the herd sizes would be decreased, this practice would be advantageous for making nucleus dairy herds.
5. In cult scheme with medium IVEP level, it was expected that the cumulative selection response amounted to one and more standard deviation units in 10 years and to two standard deviation units in 20 years.
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