PSVIII-14 Genetic change in QTLs related with nutritional value of egg in small scaled chicken populations

Abstract Commercial breeds of chickens are staying under strong selection pressure on increasing of production level. Meanwhile aboriginal breeds are conserving unique adaptation traits, helping them to survive in severe climate. Local breeds combining high resistance, but lower productivity traits are widely kept in smallholders of developing countries. Improving of egg traits in such breeds should be done by selection, not crossing with commercial breeds. Aim of our studies was genetic change of QTL loci linked with yolk size (YS) and egg mass (EM) in resource chicken breeds. Studies were done using 293 samples from Pushkin, Rhode-Island, Amroks, Chinese Silk, Yurlow crawl and Russian White (RW) breeds kept in RRIFAGB Collective Use Centre ‘Genetic Collection of Rare and Endangered Chicken Breeds. EM was recorded in age of 30 weeks. YS was evaluated using ultra sound scanner. Genotyping was performed using illumina 60K Chicken Bead Chip. GWAS studies were performed on RW breed. Sufficient associations of EM were found on chromosome 4 (rs14201361, P < 1.6e-5 & GGaluGA152718, P < 3.3e-5). Correlation of YS and EM were calculated within breeds, difference were from 0.29 to 0.65. Haploblocks were analyzed in QTL region on chromosome 11 linked with YS. Due to selection and genetic drift different haplotype blocks were formed in breeds having different YS. Shown results could be used for improving egg traits in aboriginal domestic breeds. Studies were founded by RFFI project 18-016-00114 A.