Experience of many countries with a highly developed science and dairy cattle breeding as well as scientists’ predictions indicate that breeding work with the breed should be done according to the principles of large-scale selection, which includes intensive and centralized use of bull-improvers applying deep knowledge of basic methods for assessing the qualities of breeding animals, population genetics, patterns of variation and inheritance of economically useful traits in populations and herds. This approach will allow the breeding to increase the genetic progress in the population to 60 kg of milk per cow per year.

The aim of the research was to create and improve the genealogical structure of pedigree herds in Ukrainian black-and-white dairy cattle of Kyiv region by identifying and intensive use of the the best bulls of the breed.

We used the research information of three breeding enterprises (Bila Tserkva SPE, Kyiv ОПО and the Chief Selection Centre ) as an object. The Data describes the population of Ukrainian black-and-white dairy cattle of Kyiv region.

The study has shown that using semen of bulls-improvers provided the opportunity to receive additionally 100–300 kg more milk per cow on average, and in some farms it made 500–600 kg more compared to the peers.

A comprehensive analysis of 347 sperm output of sires bulls from the three breeding enterprises of Kyiv region in the amount of 12846147 sperm dozis pointed out that only 161 (46.4 %) bulls have the assessment on the quality of offspring. Their breeding value made 325 kg of milk on average, including sires of Ukrainian black-and-white dairy cattle +219 kg, Holstein +461 kg and Dutch +252 kg of milk.

Analysis of the evaluation of the sires showed the Holstein sires (+ 461 kg milk) are better in terms of the breeding value.

Ukrainian black-and-white dairy cattle bulls possess lower breeding value compared with Holstein sires and Dutch (+219 kg of milk), but they produce the offspring more suited to the conditions of feeding and maintenance, since well as high blood offspring obtained from Holstein bulls (75% of "blood " for Holsteins) reacts to the impact of the environment dramatically and under poor maintenance and low feeding can not realize their genetic potential.

However, if the performance of a bull's mother does not significantly affect the performance of a bull's daughters, the breeding value of the parents affects the bulls straightforward evaluation of sires and his offspring, since the rate of the parent bulls accounted for 40–45 % of the effect of selection while for mothers bulls, it is 23–30 %. All this points to the need for selection among a group of parents bulls.

It is established that the existing bull-breeders obtained from 134 parents of bulls, that is, the intensity of selection makes only 2–3 son of a father. It proves the necessity of implementing the system of selection and extensive use of bull-breeders.

Our previous studies have shown that hereditary progress in herds of Ukrainian black-and-white dairy cattle is nearly completely dependent on the selection of bull- breeders (90–95 %) since even under the hardest cows culling maternal the effect of selection may increase by no more than 15 %.

Therefore, selection and breeding work of Ukrainian black-and-white dairy cattle should be directed at identifying and intensive use of outstanding sires that are largely dominated by the productive qualities of breeding stock and consistently convey their offspring.

Key words: line, population, genetic progress, selection effects, breeding value, the intensity of selection, semen, bull leaders, bull-breeders.