The aim of this paper is to predict the improvement value by the BLUP methodology - the Sire Model, of some bulls used to inseminate females exploited in condi-tions of a farm located in N-W Moldova, Romania. After comparing the main productive characters between ancestry (MT – 5260.22 KG milk) and offspring it was observed that the descendants have a higher average production in LN1, of 5470 kg milk in LN1 and a lower production in LN2, about 5210.14 kg. Even if in the population the value of h2 is 0.64 females do not phenotypically express their genetic potential. We can say that their performances are influenced by environmental factors that primarily relate to the growth technology, fee-ding and the climate in which they grow. Among the bulls for which the estimate of impro-vement value was made, the one with registration number 53791 has the best improvement value of 451.1825 kg for milk production. This male is a breeder for other traits as well.