The dissertation work presents the results of investigations on myostatin and insulin loci polymorphism and the analysis of its associations with chicken egg and meat productivity traits of lines of Ukrainian selection of Rhode Island Red and Plymouth Rock White breeds, which complement the molecular and genetic characteristic and expand the list of promising PCR-RFLR-markers of productive traits of local chicken lines.
It was established that on the G2109A mutation of myostatin gene in line 38 (Rhode Island Red) AA, AG, and GG genotypes frequencies are 0,01; 0,15 and 0,84; in the line G2 (Plymouth Rock White) – 0,05; 0,35 and 0,60; respectively. In both populations, the most common is allele G, which frequency is 0,775 in line G2 and 0,915 in line 38. It was determined that on T+3737C mutation of the insulin locus in line 38, CC, CT, and TT genotypes frequencies are 0,42; 0,43 and 0,15 respectively. In line G2, the most common genotype is TT (0,93); CT genotype frequency is 0,07; CC genotype is not identified. C and T alleles frequencies are: in line 38 – 0,635 and 0,365; in the line G2 – 0,965 and 0,035, respectively. On the A+3971G mutation of INS gene in line 38, the predominant genotype is GG (0,58); AA and AG genotypes frequencies are 0,07 and 0,35. In the population of chicken of line G2, the most common genotype is AG (0,54); AA and GG genotypes frequencies are 0,25 and 0,21; respectively. In line 38, the highest frequency has allele G (0,755), in line G2 – A (0,520).
To increase the genotyping efficiency of different chicken breeds, a method has been developed for the simultaneous determination of genotypes by T+3737C and A+3971G mutations in the chicken insulin gene, protected by the Ukrainian patent for utility model (No. 136724).
As a result of investigations on the analysis of the associations of the revealed myostatin and insulin genes polymorphism with poultry productivity traits, the desired genotypes for chickens of the studied lines were determined. Promising in the direction of meat productivity increasing are MSTN(G2109A)AG for line G2, and the complex genotype MSTN(G2109A)GGINS(A+3971G)AG – for line 38. In the direction of egg productivity increasing, the desired genotype for line 38 is INS(A+3971G)GG. Considering the nature of the associations identified between genotypes and productivity traits, as well as the genetic structure of the Ukrainian chicken lines of Rhode Island Red and Plymouth Rock White breeds, methodological recommendations have been developed regarding the formation of chicken microlines with promising genotypes, which are recommended to be taken into account in marker-associated selection programs to improve productive traits of chickens.
