Identification of growth-related loci in Korean native ducks using a dual-species single-nucleotide polymorphism chip

Body weight (BW) is an economically important trait associated with meat production in the poultry industry. Despite their desirable meat quality, Korean native ducks (KNDs) exhibit lower BWs and slower growth rates than commercial breeds that limited their competitiveness. Due to the limited availability of duck-specific single-nucleotide polymorphism (SNP) chips and the high cost of large-scale genotyping, we previously developed a dual species SNP chip applicable to both ducks and chickens. In this study, we investigated the genetic variation of growth traits in KNDs and evaluated the applicability of the developed chip. BWs from hatching to 10 weeks of age were recorded and compared with those of Pekin ducks to assess growth performance. A genome-wide association study (GWAS) was conducted for body weight at 6 weeks (BW6) and at 8 weeks (BW8), corresponding to the commercial market age and representing commercially important time points, using 232 KNDs genotyped with 30K SNPs. This result confirmed that KNDs have relatively slow growth compared to Pekin ducks. GWAS identified a significant SNP associated with BW6, and four candidate genes (ENSA, IQGAP3, ANP32E, and RAB25) were located within the genomic region surrounding the significant SNP. However, no significant SNPs were detected for BW8. These outcomes may provide insights into the genetic basis of body weight traits in ducks and offer valuable information for the genomic breeding strategies in KNDs.