The dairy industry is predicated upon progeny trying out and artificial insemination to disseminate superior genes and toughen genetic gains. Animal model evaluations were used to guage the accuracy of current selection theory in predicting selection responses when progenies are from high merit parents.Data consisted of proofs of sires. The animal model evaluation as it should be predicted a young bull merit. Genetic responses agreed with their expectations in pattern but no longer in magnitude. Responses were 70 to 85% of potential responses. The percentages of a high rank on milk, fat, or protein yield were modeled the use of logistic regression. Seven factors were significantly associated with a 5% rank for milk yield; nine factors for fat yield and eight factors for protein yield. Young bulls own PTA for protein yield building up The percentages of a best 5% rank on milk yield. The percentages were increased by 52% for milk yield and 27% for fat yield by a 1 kg building up in PTA protein. This book intended for graduate students in animal breeding and breeders provides theoretical quantitative genetics aspects that were verified the use of US dairy sire proofs from routine genetic evaluations.