EVALUATION OF BULLS OF LOCAL BREEDS BASED ON THE PRODUCTIVITY OF DAUGHTERS WITH THE USE OF MARKER ALLELES

Abstract

In order to improve the economically useful traits of the Brown Swiss breed
of cattle of the combined direction of productivity in the Smolensk Region, imported livestock was used with domestic resources. For the analysis of changes in the allele pool, EAB
locus alleles of blood groups were used as genetic markers. All studies were carried out in the
laboratory of immunogenetics of the FSBSI Federal Research Center for Bast Fiber Crops
using 52-65 proprietary reagents, unified in international tests, in accordance with established
guidelines. Between 2000 and 2020, 127 servicing bulls were used in the breeding farms of
the Smolensk Region. 60 EAB locus alleles of blood groups were identified in their genotypes. With the frequency of occurrence of more than 5%, the following ones were identified
among them: b, B2O3Y2A/2E/3G/P/Q/Y/, B2P2Y2G/Y/, G1O/, G3O1T1Y2E/3F/2G//2,
I1Y2E/2G/I/G//1. The most numerous animals were those whose genotypes contained the marker alleles G3O1T1Y2E/3F/2G//2 and B1O3Y2A/1E/3G/P/Q/Y/, which were introduced into the population by imported servicing bulls. In 2016-2020 EAB alleles B1G2KY2E/2F/2G/I/O/G//1 and
G3O1T1Y2E/3F/2I/G//2 appeared in the breed. They were introduced by Fiat 2517 and Atlet 3075
bulls. Frequency of occurrence of EAB locus alleles, which mark the inheritance of imported
servicing bulls, amounted to 0.842. EAB alleles, which are typical for the domestic Brown
Swiss breed, occurred with the frequency of 0.122. Animal genes, which were introduced by
Jersey bulls, were preserved in the genetic structure of the herds (Σ=0.023). In order to evaluate the influence of servicing bulls on the genetic potential of daughters, we analyzed some
parameters of their milk productivity in 7 breeding farms of the Smolensk Region. During the
first lactation, the difference in milk productivity of daughters that inherited different alternative alleles of the father ranged from 5 to 651 kg of milk, up to 0.21% of fat and up to 0.15%
of protein in milk. As for the maximum lactation between half-sisters, the difference was established: from 1 to 1218 kg of milk, fat – up to 0.17%, protein – up to 0.19%. By analyzing
milk yield, fat and protein in milk, it was established that daughters, which have certain markers of their father in their genotype, have superiority over their half-sisters both in the first and
maximum lactations.