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The aim of the research. The domestic breeding base is not always able to meet the need for high-quality breeding stock with high genetic potential to staff newly established enterprises or farms that increase production capacity. Therefore, in recent decades, imports of livestock from abroad have increased significantly. Thus, according to the State Statistics Service of Ukraine, annually (2016–2021) from 1.5 to 4.5 thousand heads of breeding cattle are imported to our country from Europe (Denmark, the Netherlands, Germany, Poland, Austria, Hungary, the Czech Republic). The largest share of imported breeding resources are Holstein animals. However, imported animals that are obtained and raised in other environmental conditions and genetically programmed for them do not always successfully adapt to new housing and feeding conditions. It is obvious that the adaptation processes are reflected in the level of milk productivity and indicators of lifetime use. In this regard, further study of the productive longevity of cows and the realization of the genetic potential of imported and purchased within the country of dairy cattle is relevant and of scientific and practical interest. Materials and methods of research. The study was conducted in a breeding farm for breeding Ukrainian Black-and-White dairy cattle, and since 2009 – Holstein breed ALLC "Agrosvit" Myronivskyi district of Kyiv region by retrospective analysis on the materials of primary zootechnical and breeding records. The electronic information base of the Dairy Management System of Dairy Farming “ORSEC” as of March 2020 was used for the analysis. The generated matrix of observations in the sta format generally contained information about 5099 cows for 482 variables. Of these, 3298 animals had dated information on the date of calving (2002–2019) and milk yield of first heifer. Of the 1,001 cows included in the analysis, 541 were classified as Holstein, 541 as Ukrainian Black-and-White dairy cows, and 11 as other breeds and crossbreeds. By herd or country of selection 1135 cows are included in the group of local reproduction, 35 – imported in 2003 to the farm from Hungary (first calved in 2004), 105 cows imported in 2005 from Denmark (first calving 2005–2006), 33 cows imported in 2008 year from Germany (the first calving in 2008–2009), 48 cows were purchased from SE "Yamnytsia" Tysmenets district of Ivano-Frankivsk region, 20 – in SERF "Ryhalske" Yemilchyn district of Zhytomyr region, 53 – in LLC "Agrofirma Knyazhychi" Kyiv-Sviatoshynskyi district of Kyiv region, 33 – in Sarny SRS of Sarny district of Rivne region. Research results. Comparison of group average animals of different birthplaces (countries or herds of selection) established a sometimes noticeable level of intergroup differentiation in terms of growth intensity of repair heifers, reproductive ability and milk productivity of cows for the first three and higher lactation. This may be partly due to the different conditional bloodlines of the improving Holstein breed. In terms of live weight at the age of six months, the best development is characterized by animals of SE "Yamnytsia", which exceeded the animals of Sarny SRS by 18 ± 3.2 kg or 10.7% (td = 5.63, P |