Effect Of Divergent Selection On IMF And Genetic Analysis Of Candidate Genes On Chicken

Divergent-selected lines based on intramuscularfat (IMF) of Beijing You Chicken were fed and slaughter at age of 56 and 120 day. The IMF content, growth and carcass performance, meat quality, polymorphism and mRNA expression of candidate genes were tested. Effect of divergent selection on IMF was verified, and the relationships among IMF content, meat quality, polymorphism and mRNA expression of IMF candidate genes were analysed. Results show that,1. The difference on IMF contents in muscle between divergent-selected lines had been significant after 5 generations. The IMF contents of breast and leg muscle at 120 d in up-selected line (UL) were higher than down- selected line (DL) significantly (P＜0.05).2. The growth and carcass performance of chickens could be improved by up-selection on IMF content. Compared to the DL, UL exhibited greater body weight (10.70%), carcass weight (10.70%), eviscerated yield (12.40%), breast weight (12.90%), leg Weight (14.20%) at d 120 respectively and the differences were significant (P＜0.05).3. The meat quality of chickens could be improved by up-selection on IMF content. The pHu and drip loss in UL increased and brightness (L*) in DL decreased significantly (P＜0.05).4. Genotype distribution of A-FABP was changed by divergent selection. The UL exhibited greaterBBs (18.75%) than DL. The mRNA expression of H-FABP in breast muscle and A-FABP in adipose fat differed between UL and DL at d 120 (P＜0.05) caused by divergent selection.In conclusion, effect of divergent selection through family selection on IMF content which could improve product and meat quality as well as induce the differencial expression of target genes was efficient.