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1.
海参纲线粒体基因组特征分析及分子标记探讨   总被引：1，自引：0，他引：1  
通过常规PCR和长PCR扩增获得仿刺参的线粒体DNA,进而采用鸟枪法测序、序列拼接获得仿刺参的线粒体基因组全序列.结合瓜参、拟刺参、海参及另外一个仿刺参的线粒体基因组,初步揭示了海参纲线粒体基因组的基本特征.檐手目的3个物种(仿刺参、拟刺参和海参)线粒体基因组的基因排列完全一致,且与海胆纲物种线粒体基因组的基因排列相同.隶属于枝手目的瓜参线粒体基因组的基因排列与其他海参线粒体基因组相比,发生6个tRNA基因的易位.海参纲线粒体基因组主编码基因的变异特征分析揭示了在海参类线粒体基因组所有的主编码基因中,coxl基因多态位点的比例最低,仅为29.46%;nad2、nad4、nad5三个基因的多态位点不仅比例较高,而且基因的长度较长,从而拥有最多的多态位点.因此,nad2、nad4和nad5基因可以coxl基因辅助的分子标记.  相似文献   

2.
不同规格和投苗密度对仿刺参池塘网箱保苗效果的影响   总被引：2，自引：0，他引：2  
仿刺参室外池塘网箱保苗是近年来兴起的一种半生态式的保苗方式。于2014年7—11月在仿刺参室外池塘网箱保苗期间,通过现场试验比较研究了不同投苗规格[大规格(0.093±0.004)g/头,小规格(0.024±0.001)g/头]和密度(低密度125g/m3、中密度250g/m3、高密度375g/m3)两因素对仿刺参苗生长、成活率和产量的影响。结果表明,对于同一规格的仿刺参苗,低密度组体质量与特定生长率高于中、高密度组;相同密度条件下,大规格苗种成活率显著高于小规格(P0.05),小规格低密度组仿刺参苗的成活率显著高于高密度组(P0.05),大规格低密度组仿刺参苗的成活率显著高于中、高密度组(P0.05)。不同密度组收获仿刺参苗的总产量无显著差异(P0.05),但低密度组收获仿刺参苗的净产量高于中、高密度组。通过两因素方差分析可知,规格的主效应及二者的交互作用对仿刺参苗成活率有显著的影响(P0.05),密度的主效应对仿刺参苗成活率有极显著的影响(P0.001);两因素的主效应及其交互作用对仿刺参苗总产量均无显著的影响(P0.05)。规格主效应及二者的交互作用对仿刺参苗净产量的影响不显著(P0.05),密度主效应对仿刺参苗净产量有显著的影响(P0.05)。因此,仿刺参室外网箱保苗过程中投放大规格、低密度苗种能够保证较高的成活率和净产量,而且可以节省苗种资源和饵料投喂量,降低单位面积生产成本和管理成本,提高产出投入比和经济效益。  相似文献   

3.
三疣梭子蟹生长相关 SNP 位点的鉴定   总被引：2，自引：0，他引：2  
为了发掘三疣梭子蟹(Portunus trituberculatus)与生长相关的SNP,本研究基于三疣梭子蟹比较转录组学数据,筛选出生长相关候选基因片段19条,利用该基因序列设计引物进行PCR扩增,得到总长为17 387 bp的DNA片段;通过直接测序法发现74个SNP位点,分布频率为0.43/100 bp,其中转换突变的比例为80%,颠换突变的比例为20%,转换的比例远远大于颠换,符合"transition bias"原理。C/T(G/A)突变所占比例为60%,G/T(C/A)突变占20%,A/T突变占9.33%,G/C突变占10.67%,C/T(G/A)突变所占比例最大。内含子上突变发生的频率为1.34/100 bp,外显子上仅为0.17/100 bp,说明外显子上的碱基更加保守。通过飞行质谱法,在三疣梭子蟹生长性状分离群体中成功分型了10个SNP位点;通过卡方检验和多元方差分析的方法进行性状关联分析,发现3个SNP位点与生长性状显著相关(P0.05),并且comp58070-R31位点与生长性状极显著相关(P0.01);一般线性模型的多元方差分析显示,comp58070-R31位点与体重、全甲宽、甲宽3个性状极显著相关(P0.01),与体长、体高2个性状为显著相关(P0.05);comp46623-F49位点与甲宽显著相关(P=0.05);comp49193-R333位点与甲宽显著相关(P0.05)。通过对SNP位点的多态性分析发现,三疣梭子蟹SNP标记观测杂合度(Ho)范围为0.162 8~0.833 3,期望杂合度(He)范围为0.189 6~0.591 2,并且显示SNP标记的信息量低于微卫星标记。该研究的结果将有助于推进三疣梭子蟹分子标记辅助育种进程。  相似文献   

4.
日本红刺参在分类上隶属于海参纲、刺参科、仿刺参属,体形呈圆筒状、背面隆起,上有4～6行大小不等、排列不规则的圆锥形疣足,腹面平坦,管足密集,排列成不很规则的纵带,体色红色或红褐色,背面斑杂  相似文献   

5.
为开发与草鱼生长性状相关基因及单核苷酸多态性(single nucleotide polymorphism,SNP)标记,实验采用转录组测序技术(RNA sequencing,RNA-Seq)对草鱼快长组和慢长组的肝脏、肌肉和脑组织分别进行分析,共获得31 465万条高质量短读序(clean reads),经组装得到34 147条拼接基因(unigene),平均长度为1 060 bp,其中有30 751条unigene获得注释。在肝脏、肌肉和脑组织中分别筛选到1 013、552和372个差异表达基因,并从中检测到4 580个SNP标记。采用SNaPshot技术对其中34个SNP标记在300尾草鱼生长性状极端群体中进行多态性检测和验证,30个SNP标记分型成功,准确率为88.24%。进一步采用一般线性模型分析30个SNP标记与生长性状的相关性,结果显示,unigene00810126-8014标记CC基因型的体质量、体长、体高、头长和尾柄长性状均值显著高于TT基因型。unigene00810126-2903标记AA基因型的体质量显著高于GG基因型。unigene00870394-525标记AA基因型的体质量和体长性状均值显著高于GG基因型。unigene02938762-011628标记的TT基因型与CC基因型在体质量、体长和头长性状上的差异均达到显著水平。这4个标记位于生长催乳素α基因(slα)、早期生长反应蛋白-1基因(egr-1)和肌球蛋白重链基因(myh)上。其他标记不同基因型个体间的生长性状均不存在显著差异。其中8个SNP标记在草鱼群体中的平均多态信息含量(PIC)、平均期望杂合度(H_e)和平均观测杂合度(H_o)分别为0.300、0.377和0.363,表明草鱼选育群体遗传多样性较高。本研究获得与生长性状相关的1 937个差异表达基因和4个SNP标记,为草鱼分子辅助育种研究提供基础资料。  相似文献   

6.
以福建冬季海上筏式吊笼养殖的仿刺参为对象,采用传统海带饲料和市面销售的凝胶状海参配合饲料对三种规格的仿刺参幼参(平均体质量分别为105.57、73.15和52.89 g)进行了为期60 d的投喂试验,比较了两种饲料对仿刺参幼参生长的影响。结果表明,传统海带饲料投喂组大、中、小三种规格仿刺参的特定生长率分别为(0.69±0.04)、(0.87±0.05)和(0.99±0.02)%·d-1,凝胶状海参配合饲料投喂组的特定生长率分别为(0.65±0.03)、(0.86±0.05)和(0.81±0.10)%·d-1。传统海带饲料投喂组小规格仿刺参的平均个体增重率和特定生长率均显著大于凝胶状配合饲料投喂组(P0.05),而两种饲料投喂组大、中规格间的差异不显著。因此,传统海带饲料可用于仿刺参海上筏式吊笼养殖生产,而凝胶状海参配合饲料可作为传统海带饲料的辅助饲料。  相似文献   

7.
仿刺参基因组大小测定采用流式细胞术,以鸡红血细胞DNA含量(2.5 pg/2C)为内标,用夏眠、正常和野生3个群体的仿刺参体腔细胞测定了52只刺参的单倍体基因组含量,其C-值为(0.90±0.06)pg,由此得出仿刺参基因组大小为(880.2±58.68)Mb。其中,夏眠、正常和野生群体C-值分别为(0.93±0.05)、(0.90±0.05)和(0.84±0.02)pg。运用独立样本t检验对比分析显示:(1)夏眠与正常的仿刺参基因组大小之间差异不显著,说明仿刺参基因组大小与夏眠这一生理因子不具有相关性;(2)池塘(围堰)养殖环境下与野生环境下的仿刺参基因组大小之间有显著差异,野生环境下的仿刺参基因组明显小于池塘(围堰)养殖环境下的基因组。据此推测,环境因子的改变可能对仿刺参乃至整个海参类群基因组DNA含量产生影响。实验还对C-值测定的发展和方法作了详尽的描述,同时在综合其他种类海参基因组大小研究的基础上,探讨了C-值与进化地位之间的关系。  相似文献   

8.
单核苷酸多态性(SNPs)标记在大多数物种基因组中数量巨大且分布均匀,是许多水产物种遗传研究的理想标记,因此快速发展了几种高通量、快速的SNP标记分型平台。本研究利用Golden Gate分析技术对鲤Cyprinus carpio转录组测序的1 536个SNP标记合成了一张中等密度SNP芯片,对5个鲤群体的480份样本进行基因分型。结果表明:1 235个SNP标记成功分型,约占80%;915个标记至少在一个家系中呈现多态性,占74.1%;标记最小等位基因频率(MAF)介于0.05~0.5之间,平均为0.334,其中48.9%的标记最小等位基因频率(MAF)大于平均值;5个群体中SNP标记平均多态性信息含量(PIC)在0.3左右,为中度多态,杂合度为0.010~0.990,平均为0.5左右,暗示群体具有丰富的遗传多态性,育种价值及性状改良潜力很大。本研究分型的多态性SNP标记可广泛应用于遗传多样性研究、标记-性状关联分析以及分子标记辅助育种。  相似文献   

9.
饲料转化率是鲤养殖重要的亟待改良的经济性状之一。本研究利用分布于鲤全基因组的1 536个SNP标记,分析68尾全同胞家系镜鲤Cyprinus carpio的基因分型,采用TASSEL软件的GLM和MLM模型检测与饲料转化率性状紧密关联的标记位点,发掘相关位点内的优异等位变异。本研究共获得17个与饲料转化率性状显著关联(P0.05)的SNP标记,贡献率在6.4%~16.6%之间,分布于鲤基因组第2、6、11、16、20、32、33、41,和42染色体以及Scaffold1032、1078和2323上,注释了一批饲料转化率相关的候选基因。从显著关联的标记位点内发掘了16种优异等位变异,其平均表型效应值较群体均值高6.2%,较非优势等位变异高12.5%。其中,SNP0919、SNP0167和SNP1016 3个标记的优异等位变异增减效差异最大,暗示这些标记对性状的选择效果明显。本研究发掘的饲料转化率相关的标记及优异等位变异可为鲤饲料转化率性状的分子标记辅助选择及分子设计育种提供依据。  相似文献   

10.
本研究通过高通量测序技术对引入养殖的俄罗斯红参(Apostichopus japonicus)线粒体全基因组进行随机测序并分析,结果显示,俄罗斯红参线粒体基因组全长为16111 bp,共含有37个基因,包括22个tRNA、2个rRNA (l-rRNA和s-rRNA)和13个蛋白编码基因。全序列共存在24处基因间隔和5处基因重叠区。蛋白编码基因与全序列的碱基使用均表现出A、T偏倚。13个蛋白编码基因的密码子完整,除ND1以GTG为起始密码子外,其他均以ATN为起始密码子;终止密码子都是完整密码子,除ND2与ND4的终止密码子分别为TTG与TAG外,其他终止密码子以TAA为主;氨基酸频率最高为丝氨酸Ser(S),其次为亮氨酸Leu(L)。22个tRNA长度范围为66~72 bp,2个基因存在重复,且21个基因能预测其三叶草结构。l-rRNA与s-rRNA的长度与位置不同,对碱基的使用相似。蛋白编码基因的基因排列与海参纲(Holothuroidea)、海胆纲(Echinoidea)排列顺序相同,并与海星纲(Asteroidea)及蛇尾纲(Ophiuroidea)共享基因模块。BLAST分析表明,俄罗斯红参与仿刺参(Apostichopus japonicus)同源性最高。不同海参遗传距离分析发现,俄罗斯红参与3个海域仿刺参最为接近。基于最大似然法分别根据氨基酸与核苷酸序列构建的系统发生树显示,基于核苷酸序列的建树结果更符合亲缘关系较近的海参种类间的分析。引入养殖俄罗斯红参线粒体全序列结构与分析可为后续俄罗斯红参的遗传研究及种质应用提供支持。  相似文献   

11.
The genetics of resistance to hypoxia was studied in shrimp using two approaches, heritability estimation and heterosis estimation. The heritability of resistance to hypoxia was evaluated in two populations of shrimp postlarvae families produced at different times, and heterosis was estimated through the reciprocal crosses of two genetically distinct shrimp populations at postlarvae and juvenile. Heritabilities of resistance to hypoxia in postlarvae were large and out of the range for the heritability (1.73±0.09, 1.35±0.14) regardless of population evaluated. When covariates (survival and mean total weight to postlarvae 15 days old) were introduced in the analyses to correct for effects during rearing of the larvae, the heritabilities did not change substantially for the first population, but were decreased for the second population depending on the covariate used for correction (1.15±0.10 and 1.08±0.11 for the covariates survival and total weight respectively). Those large heritabilities could be explained by the presence of confounded common environmental variance in the estimated genetic variance (maternal effects), or by dominance and epistatic effects being an important part of the estimated genetic variance. Heterosis analyses dissecting maternal effect indicated that both effects, maternal and dominance, are involved in the resistance to hypoxia at postlarvae, and that although maternal effects decreased at juvenile stage, the trait was still characterized by presenting a large heterosis value (62–65% for postlarvae and 36% for juveniles).  相似文献   

12.
Genetic parameters were estimated for survival of Macrobrachium rosenbergii using a fully pedigreed synthetic population formed by three introduced strains. The data included 107 398 progeny from 394 sires and 654 dams in six generations with a nested mating structure. The variance components and genetic parameters were estimated using a generalized linear mixed model with the probit link function. Available heritabilities in survival from the generation G3 to G5 ranged from 0.007 ± 0.020 to 0.066 ± 0.044 (P > 0.05) using a model that included the common environmental effect (c). Across generations, low heritability (0.016 ± 0.012, P > 0.05) was estimated using the model with inclusion of the c effect. There were statistically significant differences in the heritability estimates between different ponds for most generations. Moreover, the genetic correlation of survival between ponds over six generations varied from low to high (?0.0007 ± 0.17 to 0.80 ± 0.069) and was significantly different from unity. There were low correlation coefficients (?0.039 ± 0.096 to 0.342 ± 0.081) between body weight estimated breeding value (EBV) and survival EBV of families in different generations. The low heritabilities for survival are most likely caused by low genetic variation in the founder populations and reduced genetic variation because of consecutive selection.  相似文献   

13.
Variation in body weight and total length among 15 families of Phase I white bass, Morone chrysops, was evaluated in a communal pond. Trait heritabilities (h2) were estimated and family pedigrees were determined a posteriori using microsatellite molecular markers. Fry averaged 36.7 ± 2.6 mm and 0.53 ± 0.10 g across all families after 32 days of communal rearing. The number of offspring identified in our sample per family ranged between three and 28. There were significant differences between families in both body weight and length (P < 0.05). The families clustered into four overlapping groups, but family rankings differed by trait. Both traits showed low heritability (h 2 = 0.07, length; h 2 = 0.06, weight). Subsequent studies in white bass should include assessment of larger fish to obtain genetic estimates at different stages in the production cycle. This study represents the first effort to assess variation among white bass families for any growth-related trait using a communal rearing approach.  相似文献   

14.
Pacific oyster is one of the leading species in world aquaculture, but heritability estimation applying mixed‐family approach has not been actively pursued. In this study, heritability for growth‐related traits in the Pacific oyster was first estimated by creating a single cohort of 45 families in a full‐factorial mating design consisting of nine sires and five dams. A total of 270 offspring were analysed and parentage assignment inferred by six microsatellite markers achieved 100% success. All parents contributed to the spawn and a total of 42 full‐sib families were represented. Using an animal model, heritability estimates at 12 months of age were 0.49 ± 0.25 for shell height, 0.36 ± 0.19 for shell length, 0.45 ± 0.23 for shell width and 0.35 ± 0.17 for wet weight. Genetic correlation between shell height and wet weight was quite high (0.79 ± 0.25), suggesting that direct selection of shell height, which is an easily measurable trait, also improves wet weight. The results obtained in this study indicate that growth‐related traits could be improved by exploiting additive genetic effects through selective breeding.  相似文献   

15.
本研究基于全同胞组内相关法对9月龄刺参(Apostichopus japonicus)苗种体长、体重、肉刺总数3个性状的遗传力进行了评估.以前期收集、保存的刺参群体为亲本,选取了健康刺参29头,采用不平衡巢式设计方法及人工刺激采卵授精方法,按照1雌配2-5雄的原则,构建了6个母系半同胞家系及23个父系全同胞家系,至9月龄时,分别抽取每个家系30-50个后代测定相应个体的体长、体重及肉刺总数,应用数量遗传学分析和全同胞组内相关法估计刺参9月龄体长、体重和肉刺总数共3个生长性状的遗传力.结果显示,9月龄刺参体长雌性组分遗传力的估计值为0.87,雄性组分遗传力估计值为0.85,全同胞组分遗传力估计值为0.86;刺参体重雌性组分遗传力估计值为0.20,雄性组分遗传力估计值为0.73,全同胞组分遗传力估计值为0.46;肉刺总数雌性组分遗传力估计值为0.43,雄性组分遗传力估计值为0.32,全同胞组分遗传力估计值为0.37.t检验表明,体长、体重的雄性组分遗传力达到显著水平(P＜0.05),全同胞组分遗传力均达到极显著水平(P＜0.01),肉刺总数的遗传力均未达到显著水平.  相似文献   

16.
Three sets of full-sib families of Pacific white shrimp Penaeus vannamei Boone, produced from females in different reproductive condition (15, 45 and 75 days after ablation and start of production), were used to estimate heritabilities and genetic correlations of growth traits for several larval and grow-out stages of development. Heritabilities for early larval length (nauplii) were larger when estimated from families produced 45 and 75 days after ablation than when estimated from families produced 15 days after ablation, indicating a maternal effect caused by lower reproductive quality of the females used to produce the second and third sets. However, the better reproductive quality of females used to produce the first set resulted in significant density effects on larval length, presumably caused by different mortalities occurring among families during larval culture, which also resulted in an increase in the heritability values estimated for late post-larvae stages. After transfer to grow-out cages in a pond, all estimated heritabilities decreased initially, then increased again. The increase in heritabilities was associated with a negative correlation between growth and density in the cages at 58 days. Lowering densities at this age resulted in a decrease in heritability values at 97 days, but an increase again thereafter. The largest genetic correlation with abdominal weight, the trait of most interest for improvement in shrimp, was total weight. That was followed by cephalothorax weight, width of first abdominal segment, abdominal length and total length. Among these, the trait with a consistently large heritability at 58 and 97 days, and with a large genetic correlation with abdominal weight, was width of first abdominal segment. This trait might provide a secondary or indirect trait to improve abdominal weight when combined with total weight for a selection programme.  相似文献   

17.
This study evaluated the genetic variance for survival at harvest of Indian white shrimp (Fenneropenaeus indicus) using a pedigreed synthetic population generated upon collecting broodstock from different fishery grounds in Egypt. The estimated heritabilities (h2 ± SE) of survival from generations G0 to G3 ranged from 0.144 ± 0.026 to 0.008 ± 0.030 using a model that included the common environmental effect (c2). Low heritability (0.014 ± 0.015) was estimated across generations with the inclusion of common environmental effect (c2). However, the h2 of survival from G0 to G1 ranged from 0.569 ± 0.071 to 0.410 ± 0.011 when c2 was not included. The genetic correlation for survival between different ponds from G0 to G3 was moderate to high (0.79 ± 0.042 to 0.83 ± 0.012) but significantly different (P < 0.05). There were low correlation coefficients (?0.237 ± 0.089 to 0.316 ± 0.073) between body weight estimated breeding value (EBV) and survival EBV of families in four generations.  相似文献   

18.
王改芳 《畜禽业》2005,199(9):32-33
将考力代绵羊离散繁殖性状配合阈模型,分别用单性状和多性状Gibbs抽样估计遗传力。多性状Gibbs抽样时,一次对两个性状进行抽样,遗传力最后取其平均值。并用多种方法对Gibbs链的收敛进行诊断。结果表明单性状和多性状分析下的产羔数、活羔数、受精力、妊娠维持和多胎性的遗传力分别为0.097±0.052、0.100±0.036、0.119±0.058、0.103±0.043、0.130±0.041和0.305±0.049、0.296±0.047、0.016±0.012、0.015±0.010、0.261±0.045。  相似文献   

19.
刺参耳状幼体体长遗传力的估计   总被引：7，自引：2，他引：7  
基于全同胞组内相关法估计刺参(Apostichopusjaponicus Selenka)耳状幼体初中期体长的遗传力.实验中的30个亲参来自人工养殖的成体刺参群体,亲本交配采用巢式不平衡设计,通过人工授精技术,构建了8个半同胞家系和22个全同胞家系.在耳状幼体初期和中期,每个全同胞家系分别测定40～70个后代个体体长.利用SAS软件的GLM过程,计算表型变量的原因方差组分,估算体长遗传力.分析结果显示,雌性遗传方差组分均显著大于雄性遗传方差组分(P＜0.05),雌性遗传方差组分存在显著的母性效应(P＜0.05).基于父系半同胞组内相关法计算的狭义遗传力是刺参耳状幼体初中期体长狭义遗传力的无偏估计值,估计值分别为0.74和0.75.结果表明,基于刺参耳状幼体体长的加性遗传方差较大,选择育种对于刺参幼体早期生长的改良具有较大的潜力.[中国水产科学,2006,13(3):378-383]  相似文献   

20.
Large yellow croaker accounts for the largest biomass production of any maricultured fish in China. However, very little is known about the genetic parameters of its commercially important traits. As an initial step towards developing a selective breeding programme, genetic parameters of nine quantitative traits were estimated using a marker‐based method. Dorsal fin samples were collected to extract genomic DNA, and GBS method was employed to construct the libraries for sequencing. Genetic parameters were estimated by REML method through a genomic relationship matrix (G matrix) constructed by abundant genomewide SNPs. The nine traits were body weight (BWT), body length (BL), body height (BH), length/height ratio (LTH), body width (BWH), eviscerated weight (EW), gonad weight (GW), eviscerated weight/body weight ratio (REB) and swim bladder index (SBI). Estimates of heritability were 0.63 ± 0.11, 0.60 ± 0.11, 0.53 ± 0.11, 0.34 ± 0.11, 0.55 ± 0.11, 0.66 ± 0.11, 0.37 ± 0.10, 0.25 ± 0.08 and 0.71 ± 0.10 for the nine traits respectively. The relatively high heritability values may be derived from calculating the genetic relationship by high‐density SNPs. To illustrate that, we had studied on the variation of the heritability estimates with different number of SNPs evenly sampled from 29748 SNPs. The results showed that the estimates of heritability generally decreased when the number of SNPs reduced. There were relatively high phenotypic and genetic correlations between the pairs of BWT, BL, BH, BWH and EW, which indicated that genetic improvement for these traits could be accomplished merely by selecting one trait. The results obtained in this study may provide a reference for the later selective breeding programme.  相似文献   

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