略阳乌鸡褐壳蛋壳颜色量化体系的建立和遗传基础分析  

Establishment of Quantization Method and Genetic Basis Analysis of Brown Eggshell Color in the Lüeyang Black-Boned Chicken

作　　者：陈球 黄晶晶[1] 王哲鹏[1] CHEN Qiu;HUANG JingJing;WANG ZhePeng(College of Animal Science and Technology,Northwest A&F University,Yangling 712100,Shaanxi)

机构地区：[1]西北农林科技大学动物科技学院,陕西杨凌712100

出　　处：《中国农业科学》2023年第17期3452-3460,共9页Scientia Agricultura Sinica

基　　金：陕西省重点研发计划(2021NY-028);陕西省农业厅专项计划畜禽新品种培育-略阳鸡(K3031222058)。

摘　　要：【背景】褐壳蛋壳颜色与蛋壳强度、蛋内抗菌肽含量、血斑肉斑和孵化率有密切联系,是影响蛋品质和销售的一个重要的指标。然而,一些地方鸡因选育程度低,存在蛋色偏浅、均匀度差等不足,给鸡蛋的销售和品牌的打造造成不利影响。【目的】探讨以略阳乌鸡为对象,建立能灵敏度量蛋壳颜色变异的量化体系,估计品种特异性蛋壳颜色的遗传力,筛选参与蛋壳颜色调控的候选基因,为略阳乌鸡褐壳蛋壳颜色选育奠定理论基础。【方法】在略阳乌鸡蛋用系62个半同胞家系中选取841只母鸡,每只鸡收集3枚蛋,用L*a*b色度体系量化蛋壳颜色。在贝叶斯框架下,用马尔可夫链蒙特卡罗(Markov Chain Monte Carlo,MCMC)算法计算各色度指标的后验遗传力。用逆γ分布指定育种值和残差方差的先验分布。执行130000迭代,弃去前30000次迭代结果,按间隔100存储迭代结果,获得各方差组分的后验分布和各指标的后验遗传力。选取产浅褐壳、褐壳、浅绿壳的母鸡各8只,每只鸡收集3枚蛋用于蛋壳色素含量的测定。用原卟啉和胆绿素标准品建立浓度与吸光度值的回归关系,分别在670 nm和412 nm处测定胆绿素和原卟啉的吸光度,用回归法求得待测样本两种蛋壳色素的浓度。采集褐壳(n=8)和浅褐壳(n=8)母鸡的蛋壳腺,用qPCR法检测ALAS1和CPOX在蛋壳腺中的表达量。【结果】在3个色度指标中,a值递减的变化规律与褐色向绿色调过渡的视觉观感吻合度最高。L值和b值能够反映褐壳颜色深浅的变化,但在区分褐色和绿色调上存在较大误差。L值和b值分布呈现出较高的集中度,50%的样本的L值和b值集中分布于73.3—79.1和13.1—18.2之间,而a值分布更为分散,50%的样本分布于1.4—7.1之间。与上述分布特征保持一致,a值的变异系数88.2%要高于L值5.7%和b值24.0%。遗传力估计结果显示,a值主要受遗传效应调控(h2=0.77),而L值(h2=0【Background】Brown eggshell color is closely relevant to eggshell strength,concentrations of egg white antimicrobial protein and yolk carotenoid,blood and meat spots,and hatchability,and is an important index affecting quality and sale of eggs.However,due to absence of selection for eggshell color,color of brown eggs that some indigenous breeds lay is light and highly variable,which has an adverse effect on sale of eggs and creation of egg brands.【Objective】The aims of this study are to establish a quantization method that could accurately and sensitively capture the variation of eggshell color,to estimate breed-specific heritability of eggshell color and to identify candidate genes associated with eggshell color in the Lüeyang black-boned chicken(LBC),so as to provide a theoretic basis for genetic improvement of LBC eggshell color.【Method】841 hens from 62 half-sibling families of LBC breeding population were selected.Three eggs were collected from each hen,and then the eggshell color was quantified using the L*a*b color space,and posterior heritabilities of L,a,and b values were estimated in a Bayesian framework using the Markov Chain Monte Carlo(MCMC)algorithm.The prior distributions of breeding value and residual variances were set using an inverse-Gamma distribution.MCMC performed 130000 iterations,dropped 30000 iterations at the beginning and stored one every 100 iterations to obtain posterior distributions of variance components and posterior heritability estimates of color indexes.Hens that laid light brown(n=8),brown(n=8)and light blue(n=8)eggs were selected from LBC population.Three eggs were collected from each hen for the measurement of eggshell pigment,and the absorbance values were measured at 670 nm for biliverdin and at 412 nm for protoporphyrin.The concentrations of protoporphyrin and biliverdin were calculated by regression equations,which were fitted using absorbances and concentrations of standard samples.Shell glands of brown-(n=8)and light brown-shelled(n=8)hens were collected.Exp

关 键 词：略阳乌鸡 蛋壳颜色 L*a*b色度空间 遗传力 CPOX ALAS1 

分 类 号：S831[农业科学—畜牧学]