饲料效率(FE)是养猪生产中最重要的性状之一。然而,衡量它既困难又昂贵,限制收集大量数据,以便准确选择更好的FE。因此,用于遗传评估的与FE相关性状相关的单核苷酸多态性(SNPs)的鉴定对于提高预测准确性和这些性状的遗传进展具有重要意义。这项研究的目的是确定与FE相关性状显着相关的SNP:平均日增重(ADG),平均日采食量(ADFI)和饲料转化率(FCR)。我们还旨在鉴定这些性状的潜在候选基因。使用了在2386只三向杂交猪的种群上记录的表型信息,这些猪的基因型为51468个SNP。我们确定了与ADG相关的数量性状(QTL)区域的三个基因座和与ADFI相关的三个QTL区域;然而,FCR没有发现显著关联.错误发现率(FDR)≤0.005被用作宣布关联为重要的阈值。Susscrofa染色体(SSC)1上与ADG相关的QTL区域位于177.01和185.47Mb之间,其与SSC1上ADFI的QTL区域(173.26和185.47Mb)重叠。ADG的其它QTL区位于SSC12上(2.87和3.22Mb)。这些QTL区域中最重要的SNP解释了这些性状的表型变异的3.26%。与FCR相关的基因组区域的未鉴定可以通过该性状的复杂性来解释。这是ADG和ADFI之间的比率。最后,基因CDH19,CDH7,RNF152,MC4R,PMAIP1,FEM1B和GAA是在本研究中确定的QTL区域周围的1Mb窗口中发现的候选基因。其中,MC4R基因(SSC1)具有与ADG和ADFI相关的众所周知的功能。在这项研究中,我们确定了ADG的三个QTL区域(SSC1和SSC12)和ADFI的三个QTL区域(SSC1)。这些地区以前是在纯种猪种群中描述的;然而,根据我们的知识,这是第一项证实这些QTL区域在杂交猪种群中的相关性的研究。应评估本研究中鉴定的SNP和基因在结合基因组选择和标记辅助选择的预测模型中的潜在用途,以提高该群体中这些性状的预测准确性。
Feed efficiency (FE) is one of the most important traits in pig production. However, it is difficult and costly to measure it, limiting the collection of large amount of data for an accurate selection for better FE. Therefore, the identification of single-nucleotide polymorphisms (SNPs) associated with FE-related traits to be used in the genetic evaluation is of great interest of pig breeding programs for increasing the prediction accuracy and the genetic progress of these traits. The objective of this
study was to identify SNPs significantly associated with FE-related traits: average daily gain (ADG), average daily feed intake (ADFI) and feed conversion ratio (FCR). We also aimed to identify potential candidate genes for these traits. Phenotypic information recorded on a population of 2386 three-way crossbreed pigs that were genotyped for 51 468 SNPs was used. We identified three loci of quantitative trait (QTL) regions associated with ADG and three QTL regions associated with ADFI; however, no significant association was found for FCR. A false discovery rate (FDR) ≤ 0.005 was used as the threshold for declaring an association as significant. The QTL regions associated with ADG on Sus scrofa chromosome (SSC) 1 were located between 177.01 and 185.47 Mb, which overlaps with the QTL regions for ADFI on SSC1 (173.26 and 185.47 Mb). The other QTL region for ADG was located on SSC12 (2.87 and 3.22 Mb). The most significant SNPs in these QTL regions explained up to 3.26% of the phenotypic variance of these traits. The non-identification of genomic regions associated with FCR can be explained by the complexity of this trait, which is a ratio between ADG and ADFI. Finally, the genes CDH19, CDH7, RNF152, MC4R, PMAIP1, FEM1B and GAA were the candidate genes found in the 1 Mb window around the QTL regions identified in this
study. Among them, the MC4R gene (SSC1) has a well-known function related to ADG and ADFI. In this
study, we identified three QTL regions for ADG (SSC1 and SSC12) and three for ADFI (SSC1). These regions were previously described in purebred pig populations; however, to our knowledge, this is the first
study to confirm the relevance of these QTL regions in a crossbred pig population. The potential use of the SNPs and genes identified in this
study in prediction models that combine genomic selection and marker-assisted selection should be evaluated for increasing the prediction accuracy of these traits in this population.