摘要
Background
Feed intake and gain are economically important traits in beef production. The rumen wall interacts with feed, microbial populations, and fermentation products important to cattle nutrition. As such, it is likely to be a critical component in the beef steer's ability to utilize feedstuffs efficiently. To identify genes associated with steer feed intake and body weight gain traits, and to gain an understanding of molecules and pathways involved in feed intake and utilization, RNA sequencing (RNA-Seq) was performed on rumen papillae from 16 steers with variation in gain and feed intake. Four steers were chosen from each of the four Cartesian quadrants for gain × feed intake and used to generate individual RNA-Seq libraries. Results
Normalized read counts from all of the mapped reads from each of the four groups of animals were individually compared to the other three groups. In addition, differentially expressed genes (DEGs) between animals with high and low gain, as well as high and low intake were also evaluated. A total of 931 genes were differentially expressed in the analyses of the individual groups. Eighty-nine genes were differentially expressed between high and low gain animals; and sixty-nine were differentially expressed in high versus low intake animals. Several of the genes identified in this study have been previously associated with feed efficiency. Among those are KLK10, IRX3, COL1A1, CRELD2, HDAC10, IFITM3, and VIM. Conclusions
Many of the genes identified in this study are involved with immune function, inflammation, apoptosis, cell growth/proliferation, nutrient transport, and metabolic pathways and may be important predictors of feed intake and gain in beef cattle.
摘要译文
背景饲料摄入量和获得量在牛肉生产中是经济上重要的特征。瘤胃壁与饲料，微生物群体和对牛营养重要的发酵产物相互作用。因此，它很可能是牛阉牛有效利用饲料的能力的关键组成部分。为了鉴定与饲料摄取和体重增加性状相关的基因，并了解与采食和利用有关的分子和途径，对来自16头阉牛的瘤胃乳头进行RNA测序（RNA-Seq），其增益和采食量有变化。从四个笛卡尔象限的每一个中选择四个阉牛进行增加×采食量，并用于产生单独的RNA-Seq文库。结果将来自四组动物的所有定位读数的标准化读取计数分别与其他三组进行比较。此外，还评估了具有高增益和低增益以及高和低摄取量的动物之间差异表达的基因（DEG）。总共有931个基因在个体分析中差异表达。在高低动物之间差异表达了89个基因;在高，低摄取量动物中差异表达69个。在这项研究中确定的几个基因之前已经与饲料效率相关联。其中包括KLK10，IRX3，COL1A1，CRELD2，HDAC10，IFITM3和VIM。结论本研究中发现的许多基因与免疫功能，炎症反应，细胞凋亡，细胞生长/增殖，营养转运和代谢途径，可能是肉牛采食量和增重的重要预测因子。
Rebecca J. Kern[b]; Amanda K. Lindholm-Perry[b]; Harvey C. Freetly[b]; Warren M. Snelling[b]; John W. Kern[c]; John W. Keele[a]; Jeremy R. Miles[b]; Andrew P. Foote[b]; William T. Oliver[b]; Larry A. Kuehn[b]; Paul A. Ludden[a]. Transcriptome differences in the rumen of beef steers with variation in feed intake and gain ☆[J]. Gene, 2016,586(1): 12–26