INRA, UR83 Recherches Avicoles, F-37380 Nouzilly, France.
Genet Sel Evol. 2014 Apr 3;46(1):25. doi: 10.1186/1297-9686-46-25.
Improving digestive efficiency is a major goal in poultry production, to reduce production costs, make possible the use of alternative feedstuffs and decrease the volume of manure produced. Since measuring digestive efficiency is difficult, identifying molecular markers associated with genes controlling this trait would be a valuable tool for selection. Detection of QTL (quantitative trait loci) was undertaken on 820 meat-type chickens in a F2 cross between D- and D+ lines divergently selected on low or high AMEn (apparent metabolizable energy value of diet corrected to 0 nitrogen balance) measured at three weeks in animals fed a low-quality diet. Birds were measured for 13 traits characterizing digestive efficiency (AMEn, coefficients of digestive utilization of starch, lipids, proteins and dry matter (CDUS, CDUL, CDUP, CDUDM)), anatomy of the digestive tract (relative weights of the proventriculus, gizzard and intestine and proventriculus plus gizzard (RPW, RGW, RIW, RPGW), relative length and density of the intestine (RIL, ID), ratio of proventriculus and gizzard to intestine weight (PG/I); and body weight at 23 days of age. Animals were genotyped for 6000 SNPs (single nucleotide polymorphisms) distributed on 28 autosomes, the Z chromosome and one unassigned linkage group.
Nine QTL for digestive efficiency traits, 11 QTL for anatomy-related traits and two QTL for body weight at 23 days of age were detected. On chromosome 20, two significant QTL at the genome level co-localized for CDUS and CDUDM, i.e. two traits that are highly correlated genetically. Moreover, on chromosome 16, chromosome-wide QTL for AMEn, CDUS, CDUDM and CDUP, on chromosomes 23 and 26, chromosome-wide QTL for CDUS, on chromosomes 16 and 26, co-localized QTL for digestive efficiency and the ratio of intestine length to body weight and on chromosome 27 a chromosome-wide QTL for CDUDM were identified.
This study identified several regions of the chicken genome involved in the control of digestive efficiency. Further studies are necessary to identify the underlying genes and to validate these in commercial populations and breeding environments.
提高消化效率是家禽生产的主要目标，这样可以降低生产成本，使替代饲料的使用成为可能，并减少粪便的产生量。由于消化效率的测量比较困难，因此识别与控制该性状相关的基因的分子标记将是选择的有用工具。在低蛋白平衡时，对喂食低质量日粮的动物在三周龄时测量的低或高蛋白能量值（AME n）进行了低或高蛋白能量值（AME n）的选择，在 F2 杂交中，对 820 只肉用鸡进行了 QTL（数量性状基因座）的检测。D-和 D+线之间的差异选择。鸟类被测量了 13 个特征，这些特征可以描述消化效率（AME n，淀粉，脂肪，蛋白质和干物质的消化利用率系数（CDUS，CDUL，CDUP，CDUDM）），消化道解剖结构（前胃，肌胃和肠道的相对重量以及前胃加肌胃（RPW，RGW，RIW，RPGW），肠道的相对长度和密度（RIL，ID），前胃和肌胃与肠道重量的比例（PG / I）；以及 23 日龄时的体重。对 28 条常染色体，Z 染色体和一条未分配的连锁群上分布的 6000 个 SNP（单核苷酸多态性）进行了动物基因型分析。
检测到 9 个与消化效率性状相关的 QTL，11 个与解剖结构相关的 QTL和 2 个与 23 日龄体重相关的 QTL。在第 20 号染色体上，CDUS 和 CDUDM 的两个基因组水平上的显着 QTL共定位，即两个在遗传上高度相关的性状。此外，在第 16 号染色体，第 23 号和第 26 号染色体上的 AMEn，CDUS，CDUDM 和 CDUP 的染色体宽度 QTL，第 16 号和第 26 号染色体上的共定位 QTL 用于消化效率和肠道长度与体重的比值，以及第 27 号染色体上的 CDUDM 的染色体宽度 QTL。
本研究确定了参与控制消化效率的鸡基因组的几个区域。需要进一步的研究来鉴定潜在的基因，并在商业种群和繁殖环境中验证这些基因。
