Epistatic Interaction Between LEP and MYF5 Is Associated with Carcass Traits in Holstein–Friesian Bulls

This study aims to investigate the relationship between carcass and meat quality traits and Insulin-like growth factor 1 (IGF1), myogenic factor 5 (MYF5) and leptin (LEP) genes in Holstein-Friesian bulls. One hundred three cattle were genotyped using the PCR-RFLP method. Afterwards, the relationship of IGF1, MYF5 and LEP genes with live weight, hot carcass weight, chilled carcass weight, dressing percentage, musculus longissimus dorsi, Warner-Bratzler shear force, cooking loss, chilling loss, water holding capacity, carcass length, chest width, and meat color parameters (L*, a*, b*) were examined. Trade-offs between carcass and meat quality were assessed using a Pareto front approach, where non-dominated genotype combinations were identified as the best attainable balance between yield and quality. No significant association was observed between IGF1, MYF5, and LEP genes individually and traits (P>0.05). However, LEP × MYF5 interaction was observed in association with live weight, hot carcass weight, and chilled carcass weight traits (P