Guo Y M, Zhang Z Y, Ma J W, Ai H S, Ren J, Huang L S
J Anim Sci. 2015 Apr;93(4):1481-9. doi: 10.2527/jas.2014-8655.
Feeding efficiency is a multifactorial and economically important trait in pigs. Genetic improvement of feeding efficiency will greatly benefit the pig industry. In the past decades, the hog market weight has increased worldwide. However, whether the genetic architecture of feeding efficiency is same or not at early and late fattening periods is unclear. To map genomic regions for feed efficiency and feeding behavior traits at early (n ≥ 384) and late (n ≥ 334) growth stages in pigs, we performed genomewide association studies for feed to gain ratio (FCR), residual feed intake (RFI), daily feed intake, daily visit times, daily feeding time (DFT), feed intake per second (FIPS), and feed intake per visit during 3 periods (2 stages and overall) in a White Duroc × Erhualian F2 intercross population. Six chromosomal regions showed significant association with these traits, of which 4 loci were reported for the first time. Our results confirmed the QTL of FCR around 34 Mb on SSC7 and RFI around 134 Mb on SSC12. Of note, 2 regions were associated with more than 1 trait. One was around 36 Mb on SSC7, and there were 47 and 67 SNP associated with FCR from 120 to 210 and from 120 to 240 d, respectively. The top SNP is located in a 2.88-Mb linkage disequilibrium (LD) block that harbors 44 genes. We propose the high mobility group AT-hook 1 gene as a plausible candidate gene in this region. The other was evidenced around 53 Mb on SSC12, which had multiple association signals for DFT and FIPS. The top SNP is located in a 211-kb LD block that harbors only 1 annotated gene, WSCD1, which encodes a protein with sulfotransferase activity and involves the glucose metabolism and, therefore, appears to be a plausible candidate gene. Except the region on SSC12 associated with DFT at both stages, the rest of the regions associated with the traits at only 1 stage, so the genetic architectures of the 2 stages are not same.
饲料效率是猪的一个多因素且具有重要经济意义的性状。饲料效率的遗传改良将极大地造福养猪业。在过去几十年里，全球生猪上市体重有所增加。然而，育肥早期和晚期饲料效率的遗传结构是否相同尚不清楚。为了绘制猪早期（n≥384）和晚期（n≥334）生长阶段饲料效率和采食行为性状的基因组区域，我们在大白杜洛克×二花脸F2杂交群体中，对3个时期（2个阶段及总体）的料重比（FCR）、剩余采食量（RFI）、日采食量、每日访问次数、每日采食时间（DFT）、每秒采食量（FIPS）和每次访问采食量进行了全基因组关联研究。六个染色体区域与这些性状显著相关，其中4个位点是首次报道。我们的结果证实了SSC7上约34 Mb处的FCR QTL和SSC12上约134 Mb处的RFI QTL。值得注意的是，2个区域与多个性状相关。一个在SSC7上约36 Mb处，在120至210天和120至240天分别有47个和67个与FCR相关的SNP。顶级SNP位于一个2.88 Mb的连锁不平衡（LD）块中，该块包含44个基因。我们提出高迁移率族AT钩1基因是该区域一个可能的候选基因。另一个在SSC12上约53 Mb处得到证实，该区域对DFT和FIPS有多个关联信号。顶级SNP位于一个211 kb的LD块中，该块仅包含1个注释基因WSCD1，其编码一种具有磺基转移酶活性的蛋白质并参与葡萄糖代谢，因此似乎是一个可能的候选基因。除了在两个阶段均与DFT相关的SSC12上的区域外，其余区域仅在一个阶段与性状相关，因此两个阶段的遗传结构不同。
