Вплив країни походження та інбридингу на продуктивність бугаїв основних комерційних порід України

Abstract

Goal. To monitor the productivity of Holstein, Ukrainian black and red-spotted dairy bulls, which were allowed to reproduce breeding stock in 2021, depending on the country of birth, quality of offspring, and degree of inbreeding to preserve the gene pool, selection methods, and improvement of economically useful traits in offspring. Methods. The study was conducted on bulls of Holstein (660 heads), Ukrainian red-spotted (65), and Ukrainian black-spotted (45 heads) dairy breeds, assessed by the quality of offspring in the country of birth. The average values of the selection index (SI), milk yield, fat and protein, and the limits of traits were determined by the methods of mathematical statistics. Results. Among Holstein bulls, most were born in the United States, Ukraine, and Canada. The daughters of Holstein bulls of Ukrainian origin had the least milk yield for lactation (2,801 kg), and the Canadian had the highest (14,302 kg). SI bulls of the Ukrainian red-spotted dairy breed were at the level of – 1051…+1426. Daughter descendants of bulls of this breed had milk yield for lactation 2559–10209 kg, fat and protein content in milk 3.41–4.18 and 2.83-3.42%, respectively. SI of bulls of the Ukrainian black-spotted dairy breed made – 1051…+1122, and milk yield of cows for lactation of 2022-9064 kg of milk with the fat content of 3,42–4,05% and protein — 3,04–3,23%. In the group of Holstein bulls, 82% of animals were inbred animals, in the Ukrainian red-spotted dairy breed — 68%, and in the Ukrainian black-spotted dairy breed — 51%. The highest milk yield for the daughters was provided by the breeders of Holstein and Ukrainian black-spotted dairy breeds of moderate inbreeding, Ukrainian red-spotted dairy breeds — distant. Conclusions. To increase milk yield in daughter offspring, it is advisable to use bulls of Holstein and Ukrainian black-spotted dairy breeds of moderate inbreeding (Fx=1.56–12.4%), Ukrainian red-spotted dairy breed — distant (Fx=0.2–1.55%).