The article presents the results of testing 4 breeding bulls by the quality of offspring, by the method (with simultaneous) testing of bulls by their own productivity during control cultivation, well-known factory lines of Viscount FR-11, Shaman 1161k, Peony 6118k, Bindweed 712k according to the traditional system and using the Growsafe system, with an assessment of the quality of freshly obtained seed. Currently, the Growsafe technology is being implemented in Galitsky LLP of the Pavlodar region. The object of research were Kazakh white-headed bulls from each evaluated bull-producer (bull KZT183665377, Arzamas KZT183248538, Pamir KZT183251512, Bos KZT183220355) in the amount of 57 heads born in 2021. During the period of control rearing, experimental bulls of different genotypes showed different growth rates from 790 to 1428 g per day. During visual control of 57 semen samples from the studied bulls, the indicators (ejaculate volume, mobility, color, density, smell) were recognized as acceptable for the use of bulls for their intended purpose. According to the results of studies on the evaluation of producer bulls, the Pamir bull KZT183251512 with a complex index of 103.0 is an improver, the Arzamas bull KZT183248538 is a neutral with a complex index of 102.3, the deteriorators are the bull KZT183665377 – 95.1 and the Bos KZT183220355 – 99.3.