This study is aimed to conduct a genetic analysis of Shaoxing breed ducks with different levels of egg production for 19 microsatellite loci. The total number of the Shaoxing breed was selected 183 ducks. Based on the result accounting for the mass of demolished eggs were formed four experimental groups with different egg masses. In the ducks of the I group, the egg mass fluctuated within 60-65 g, in II-th from 65-70 g, and in groups III and IV-from 70- 75 and 75-80 g, respectively. On the average, this indicator in groups was: І - 63,63 ± 0,257 g; ІІ - 68.04 ± 0.172 g; III - 72,64 ± 0,179 and in IV - 77,12 ± 0,277 g. Based on the microsatellite analysis, the frequency of the alleles and genotypes of the seven microsatellite loci in the animals of the experimental groups - APL2, APL23, APL83, APL82, APL81, APL80, APL79 - was determined. Among the seven studied microsatellite loci, it was found that only one was monomorphic - APL83. The number of alleles (Na) varied in groups of 2 (APL82 - groups I, II and III) to 13 (APL23 - group II). The homozygote and heterozygote varied according to the group and the locus. On average 33% of ducks were homozygotes, and the number of heterozygotes ranged from 66 to 68%. The highest homozygosity rate was observed in the APL79 locus, on average it was 61%. In the studied groups, the actual heterozygosity varied from 0.333 (group I, APL79) to 0.7 (group III, APL23). The highest index of actual heterozygosity (Hobs) had the locus APL80 (0.667-0.687), the smallest value of the actual heterozygosity index had the APL 79 locus (0.333-0.489). As a result of the analysis of the polymorphic index, the APL23 locus was the largest indicator. It was found that with the increase of individuals with genotype 101, the average weight of eggs in the group from group I (0.413) to IV (0.5) increases. The obtained results indicate the prospective use of this locus for the search for a candidate gene, the polymorphism of which is related to the weight of the egg.
аnas platyrhynchos, Shaoxing breed, microsatellite loci, frequency of alleles, egg production