Li Wei, Zheng Maiqing, Zhao Guiping, Wang Jie, Liu Jie, Wang Shunli, Feng Furong, Liu Dawei, Zhu Dan, Li Qinghe, Guo Liping, Guo Yuming, Liu Ranran, Wen Jie
State Key Laboratory of Animal Nutrition; Key Laboratory of Animal (Poultry) Genetics Breeding and Reproduction, Ministry of Agriculture, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
College of Animal Science and Technology, China Agricultural University, Beijing, 100193, China.
Genet Sel Evol. 2021 Feb 6;53(1):13. doi: 10.1186/s12711-021-00608-3.
Feed accounts for about 70% of the total cost of poultry meat production. Residual feed intake (RFI) has become the preferred measure of feed efficiency because it is phenotypically independent of growth rate and body weight. In this study, our aim was to estimate genetic parameters and identify quantitative trait loci (QTL) for feed efficiency in 3314 purebred broilers using a genome-wide association study. Broilers were genotyped using a custom 55 K single nucleotide polymorphism (SNP) array.
Estimates of genomic heritability for seven growth and feed efficiency traits, including body weight at 28 days of age (BW28), BW42, average daily feed intake (ADFI), RFI, and RFI adjusted for weight of abdominal fat (RFIa), ranged from 0.12 to 0.26. Eleven genome-wide significant SNPs and 15 suggestively significant SNPs were detected, of which 19 clustered around two genomic regions. A region on chromosome 16 (2.34-2.66 Mb) was associated with both BW28 and BW42, and the most significant SNP in this region, AX_101003762, accounted for 7.6% of the genetic variance of BW28. The other region, on chromosome 1 (91.27-92.43 Mb) was associated with RFI and ADFI, and contains the NSUN3 and EPHA6 as candidate genes. The most significant SNP in this region, AX_172588157, accounted for 4.4% of the genetic variance of RFI. In addition, a genomic region containing the gene AGK on chromosome 1 was found to be associated with RFIa. The NSUN3 and AGK genes were found to be differentially expressed in breast muscle, thigh muscle, and abdominal fat between male broilers with high and low RFI.
We identified QTL regions for BW28 and BW42 (spanning 0.32 Mb) and RFI (spanning 1.16 Mb). The NSUN3, EPHA6, and AGK were identified as the most likely candidate genes for these QTL. These genes are involved in mitochondrial function and behavioral regulation. These results contribute to the identification of candidate genes and variants for growth and feed efficiency in poultry.
饲料成本约占禽肉生产成本的70%。剩余采食量（RFI）已成为衡量饲料效率的首选指标，因为它在表型上独立于生长速度和体重。在本研究中，我们的目的是利用全基因组关联研究估计3314只纯种肉鸡饲料效率的遗传参数并鉴定数量性状位点（QTL）。使用定制的55K单核苷酸多态性（SNP）芯片对肉鸡进行基因分型。
对包括28日龄体重（BW28）、BW42、平均日采食量（ADFI）、RFI以及根据腹部脂肪重量调整后的RFI（RFIa）在内的7个生长和饲料效率性状的基因组遗传力估计值在0.12至0.26之间。检测到11个全基因组显著SNP和15个提示性显著SNP，其中19个聚集在两个基因组区域周围。16号染色体上的一个区域（2.34 - 2.66 Mb）与BW28和BW42均相关，该区域最显著的SNP AX_101003762占BW28遗传方差的7.6%。另一个区域在1号染色体上（91.27 - 92.43 Mb），与RFI和ADFI相关，包含NSUN3和EPHA6作为候选基因。该区域最显著的SNP AX_172588157占RFI遗传方差的4.4%。此外，发现1号染色体上包含AGK基因的一个基因组区域与RFIa相关。发现NSUN3和AGK基因在高RFI和低RFI雄性肉鸡的胸肌、大腿肌肉和腹部脂肪中差异表达。
我们鉴定出了BW28和BW42的QTL区域（跨度0.32 Mb）以及RFI的QTL区域（跨度1.16 Mb）。NSUN3、EPHA6和AGK被确定为这些QTL最可能的候选基因。这些基因参与线粒体功能和行为调节。这些结果有助于鉴定家禽生长和饲料效率的候选基因及变异体。
