USING OF GENETIC-POPULATION STUDIES RESULTS FOR ASSESSMENT OF SELECTION WORK IN DAIRY CATTLE POPULATIONS

The article presents the results of complex research that continues previous work aimed at determining polymorphism CSN2, PRL, LEP, and TNF-α loci analyzing productivity dairy cattle with different genotypes for these loci. goal is to analyze selection populations cows based on typing individuals allelic variants loci, which are associated economically valuable traits but not directly evaluated by traditional phenotype-based methods. To data, observed (Ho) expected (He) heterozygosity Wright's fixation index (Fis) were used. Individual animal was performed using AS-PCR (CSN2), SSCP (TNF-α), PCR-RFLP (PRL, LEP) studies revealed an excess heterozygous CSN2 a significant predominance homozygous LEP locus in population Ukrainian Black-and-White cows. For prolactin (PRL) leptin (LEP) genes, deviation from genetic equilibrium shown due increase number individuals. In Red-and-White cows, high level inbreeding (39%) found PRL locus, reflected state (χ2 = 13.50). case beta-casein situation opposite, marked (-0.24 -0.18, respectively), no deviations values 2.06 2.42, respectively). both populations, there changes ratio alleles several investigated, impossibility fixing desired breeding methods demonstrated. Based comparative analysis types DNA markers (AS-PCR, SSCP, PCR-RFLP), sensitivity Ho, He, Fis parameters established, should be taken into account when conducting genetic-population studies. Keywords: polymorphism, population, allele, genotype, homozygosity, variability, fixation.