Reproductive capacity of cows obtained from Holstein, Montbeliard, and Norwegian red breeders

Abstract

Goal. To study the level of reproductive capacity of cows obtained from breeders of Holstein, Montbeliard, and Norwegian Red breeds. Methods. Analysis of experimental studies on the application of effective breeding methods, theoretical analysis, formulation of hypotheses, genealogical, biometric, and statistical methods, and assessment of productive qualities of animals, which was carried out during 2019–2023. Results. Animals were evaluated according to reproductive capacity, taking into account the structure of their genotype. It was established that offspring with high growth intensity were produced by breeders of the Montbeliard breed: the first calvings took place at the age of 22.6–24.9 months. (P>0.999), the live weight of firstborns was 588.4–605.3 kg (P>0.999). Local cows of the first generation had a 16–52 day (P>0.999) shorter service period, 1.5–2.0 times (P > 0.999) lower insemination index, among them a higher proportion of cows inseminated after the first insemination (+13, 1+18.3% of the population) was observed. During the backcrossing of first-generation crossbreeds with breeders of the Holstein breed, indicators of the reproductive capacity of cows decreased. Conclusions. The actual parameters of the reproductive capacity of cows obtained as a result of different combinations of genotypes of parental pairs did not correspond to the optimal values, which was natural for high-yielding dairy cattle. The improvement of the reproductive capacity of dairy cattle was facilitated by the crossbreeding of Ukrainian red-spotted and black-spotted dairy cows with breeder bulls of the Montbeliard and Norwegian red breeds.