Abstract
Recently, an important element in improving the genetic traits of dairy cattle on commercial farms is the use of interbreeding (crossbreeding). The use of crossbreeding makes it possible to use a variety of additive genetic levels between breeds to grow individuals with higher economic potential. The aim of this study was to analyze the development of udder parameters in crossbred first-borns compared to purebred counterparts and to study the indicators of milk production during milking. The research was conducted on the first-born Ukrainian black-spotted dairy breed and first-generation crossbreeds obtained by crossing with the Brown Swiss breed and on the Ukrainian red-spotted dairy breed and first-generation crossbreeds obtained by crossing Ukrainian red-spotted dairy breed with Montbeliarde breed. Two groups of purebred and local first-borns were formed in both farms. Both farms use the same type of year-round feeding of cows with complete feed mixtures. The study was performed on first-born cows during weaning (2–3 months of lactation). It was found that local first-borns obtained by crossing red-spotted and Montbeliarde breeds outnumbered purebred red-spotted analogues in terms of measurements and udder indices. The opposite situation was observed in local first-borns obtained as result of crossing black-spotted and Brown Swiss breeds, which were inferior in these characteristics to purebred black-spotted analogues. In purebred black and red-spotted cows, the rates of single and daily milking were higher than in local ones. Also, purebred first-borns had a longer duration of single milking, indicators of average and maximum intensity of milk production and milk yield in the first 3 minutes. Prospects for further research are to study the productivity for completed lactation, the quality of milk and the duration of the service period.