Abstract

Feed efficiency ( FE ) is important in the poultry industry because feed accounts for 70% of total poultry production expenses. The elongation of very-long-chain fatty acid protein 2 ( ELOVL2 ) and oxysterol binding protein-like 8 ( OSBPL8 ) genes are promising candidates for influencing FE owing to their potential roles in lipid metabolism. The genetic effects by which ELOVL2 and OSBPL8 influence FE remain unclear. Therefore, this study aimed to investigate the associations between SNPs in OSBPL8 and ELOVL2 and FE traits in meat-type ducks. Genomic DNA was extracted from 505 ducks for primer design, PCR amplification, and target gene sequencing. Polymorphism analysis identified two SNPs in OSBPL8 (g.40194710T > A and g.40194759A > G) and two in ELOVL2 (g.95803706G > A and g.95803927G > A). Both ELOVL2 SNPs were significantly associated with feed conversion ratio ( FCR ), residual feed intake ( RFI ) ( P < 0.01), and ADFI ( P < 0.05). For OSBPL8 , the g.40194710T > A locus was associated with FCR and ADFI ( P < 0.05), whereas the g.40194759A > G locus was associated with RFI ( P < 0.05). Notably, combined genotype analysis indicated that the AAAATAAG genotype exhibited lower FCR and RFI values than the other genotype combinations ( P < 0.05). In conclusion, polymorphisms in OSBPL8 and ELOVL2 are significantly associated with FE traits in meat-type ducks, offering valuable molecular markers for selecting breeding pairs with enhanced feed utilization ability.