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1.
Maternal effects have been observed to interact with genotypic and environmental influences to structure offspring phenotypes across a wide variety of taxa. In fishes, maternal effects may be especially important due to their potential influence on development and survival during early ontogeny – a period with high potential for population regulation. While previous studies have confirmed that maternal effects on offspring phenotype are common in fishes, the consistency with which they positively affect offspring fitness throughout early ontogeny remains largely unknown. We examined maternal effects on offspring fitness by quantifying relationships between maternal (length, mass and age), egg (diameter, mass and density) and larval traits (length, yolk‐sac volume and survival) in yellow perch (Perca flavescens). Consistent with several past studies, positive relationships among maternal and egg traits were evident. While egg mass was positively related to larval size at hatching, direct relationships between maternal and larval metrics were not apparent. Larval survival appeared to have two critical periods; in contrast with expectations, survival in the first 5 days posthatch was strongly negatively related to female size and age, while survival over the following 9 days was unrelated to maternal traits. Throughout the study, survival was positively related to yolk‐sac volume. Our unexpected observation of a negative relationship between maternal size and age and initial larval survival indicates that maternal effects may not be consistent throughout larval ontogeny. In fact, maternal effects appear to be dynamic influences on offspring fitness, and may have complex effects on individual‐ and population‐level reproductive success.  相似文献   

2.
为了探索草鱼(Ctenopharyngodon idella)线粒体DNA(mitochondrial DNA,mt DNA)多态性对生长性状的影响,鉴于mt DNA的母性遗传特征,本研究基于2011年繁殖用的20尾母本的D-loop序列信息,与通过亲子鉴定获得的853尾40日龄子代的体长、体质量进行关联分析。结果显示,草鱼6种D-loop单倍型对生长性状表型差异具有极显著影响(P0.01);其中,单倍型为Hap16的子代的体长最大,并显著大于单倍型为Hap4的子代的体长(P0.05);单倍型为Hap18和Hap16的子代的体质量较大,依次大于其他单倍型子代的体质量,并显著大于单倍型为Hap4的子代的体质量(P0.05)。此外,草鱼D-loop序列各变异位点基因型对生长性状的影响水平不同;其中,Site01、Site06和Site07等3个位点对体长的差异存在显著影响(P0.05),Site06和Site07等2个位点对体质量的差异存在显著影响(P0.05)。研究表明,草鱼D-loop序列变异对子代生长性状具有显著影响,推测在草鱼生长性状改良的选育进程中,可以利用mt DNA多态性信息进行辅助选择。  相似文献   

3.
Reciprocal differences have been observed widely for given traits in fish breeding programs, but maternal and paternal effects and heritable extranuclear genetic effects have often been omitted in the evaluation of genetic variance. In this study, we have applied a mixed genetic model to conduct a complete diallel cross using three varieties of red common carp (Cyprinus carpio L.), namely, C. carpio. var. singuonensis, C. carpio var. wuyuanensis and C. carpio var. color. Parental and direct (additive and dominance) genetic effects for growth-related traits at 8 and 20 months post-hatch were analyzed. At 8 months post-hatch, only significant additive and dominance variances were observed, while maternal and paternal variances were low and non-significant in the traits evaluated: body weight, total length, standard length, pre-dorsal height, pre-dorsal width, caudal peduncle length, and caudal peduncle height. At 20 months post-hatch, with the exception of significant additive and/or dominance variances, maternal variances were significant for the traits of body weight, pre-dorsal height, pre-dorsal width, and caudal peduncle height, and the paternal variance was significant only for total length. The maternal effects in the common carp had greater genetic influence on offspring than the paternal effects. Female C. carpio var. wuyuanensis were more suitable as brooders than males, but both female and male C. carpio var. color can be used as brooders according to breeding programs of improved traits. Cyprinus carpio var. singuonensis was the worst brooder of the three varieties of common carp evaluated.  相似文献   

4.
The selective and environmental effects of captivity on several fitness‐correlated traits were assessed in smolts of endangered Atlantic salmon, Salmo salar L., from the inner Bay of Fundy, produced via artificial spawning and released into the wild as juveniles. Smolts were sampled as they migrated downstream and identified through microsatellite‐based parentage analysis as offspring of either wild‐spawning adults or adults that were spawned in captivity. Overall, captive‐origin smolts exhibited a significantly later run timing and smaller body size than wild smolts. Significant differences in run timing and body size were also found between captive‐origin smolts that had experienced rearing environments that differed in duration of captivity and thermal regime. Significant differences in run timing, fork length and weight were found between first and second generation captive‐origin smolts, although the expression of these differences depended on the rearing environment experienced, suggesting a possible genotype by environment effect. The ratio of effective‐to‐census number of breeders that produced the captive‐origin smolts was higher than that of the wild‐origin smolts due to successful captive breeding management practices. These results have direct implications for captive breeding and rearing programmes for salmonids and wider implications for understanding the rates of evolutionary and environmentally induced change that can occur in captivity.  相似文献   

5.
Blunt snout bream (Megalobrama amblycephala) is an herbivorous freshwater fish species native to China and has been recognized as a main aquaculture species in the Chinese freshwater polyculture system with high economic value. The genetic parameter estimates for important economic traits are needed for its selective breeding. The aim of this study was to estimate the heritabilities for its growth‐related traits and explore the genetic and phenotypic correlations among the traits using microsatellite‐based pedigree approach. Offspring from a mass‐spawning of 92 broodstocks (42 sires and 50 dams) were reared in a communal pond and nine microsatellites were used to identify the parents of each sampled offspring. Of 749 offspring randomly selected, 708 (94.53%) could be assigned directly to a single parental pair, which was used for heritability estimates. Data were analysed using the method of restricted maximum likelihood (REML) using animal model and the results showed that the heritabilities of body weight, body length, total length and body height were 0.65, 0.53, 0.53 and 0.50, respectively. High genetic correlations were found among these four traits. According to these results, selection for growth seems to be feasible in M. amblycephala and the other growth traits will be heightened accordingly with the selection based on body length.  相似文献   

6.
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   

7.
Multiple spawnings are special reproductive tactics that many fish evolved to obtain different types of direct and/or indirect spawning benefits. This has led to two pertinent questions: (a) what types of benefit does a commercially important fish provide during multiple induced spawnings annually? and (b) is there any trade‐off between traits during these spawnings? To address these questions, the present study was carried out with two separate experiments during two spawning events of an Indian major carp (Catla catla) to assess: (a) male's spawning performances and (b) female's spawning performances. The male's spawning data revealed that they produced significantly higher amount of milt and hatchlings during the first spawning, while they significantly reduced hatchling deformation rate, enhanced offspring survival rate and enlarged offspring body size during the second spawning. The female's spawning information unveiled no significant differences in total egg weight, hatching rate and hatchling deformation rate between the first and second spawning. However, females had significantly higher offspring survival rate during the first spawning and enhanced offspring body size during the second spawning. Interestingly, the analysis of trait associations revealed that males allocated energy with a trade‐off between milt weight and offspring survival rate, whereas females showed a trade‐off between hatching rate and offspring survival rate. Thus, the study provides some important information for carp breeders and associated stakeholders to know which spawning season is preferable for the higher production of eggs, milt and good quality larvae.  相似文献   

8.
利用4尾鞍带石斑鱼冷冻精子与27尾云纹石斑鱼雌鱼授精建立父系半同胞家系28个,在家系鱼苗生长到130 d时,从所有家系中共选取1294尾鱼苗,对其全长、体长、头长、体高和体质量5个生长性状进行测量。利用单因素方差分析法比较4组父系半同胞家系的生长性能,利用线形混合模型(line mixed mode)对母本和父本遗传效应进行预测,利用最小范数二次无偏估计法(MINQUE)对5个生长性状方差组分进行估计,利用"加性-显性"模型对生长性状遗传相关、遗传力进行估计,采用调整无偏预测法(adjusted unbiased prediction,AUP)预测父母本的加性及显性随机遗传效应。结果显示,5个生长性状之间的加性、显性、基因型和表现型遗传相关基本达到了显著或极显著水平;5个性状的狭义遗传力为(0.5 2 1±0.0 2 0)~(0.8 0 5±0.0 1 8),广义遗传力为(0.5 2 1±0.017)~(0.832±0.011)。27个雌性亲本中有7个(5766、6436、5779、5798、5782、6440、5790)在5个生长性状上达到了极显著的正向加性效应,4个雄性亲本中有1个(8920)达到了极显著的正向加性效应,其后代生长指标显著高于其他雄性的后代。28个杂交组合中有7个(5766*5777、6436*8932、5779*8932、5798*8932、5782*8932、6440*8920、5790*8920)在头长、体高和体质量3个性状上达到了显著或极显著的正向显性效应。本研究首次开展了鞍带石斑鱼冷冻精子与云纹石斑鱼远缘杂交及遗传效应预测研究,为石斑鱼远缘杂交育种技术和新品种培育提供了丰富的科学依据。  相似文献   

9.
Genetic parameters were estimated for growth‐related traits and survival of the Kuruma shrimp Marsupenaeus japonicus based on 66 families, including 30 paternal half‐sib families, which were obtained using artificial insemination of two females by each male. The variance components for growth‐related trait and survival were estimated using a single‐trait animal model and a sir‐dam model, respectively, and genetic parameters were estimated using the restricted maximum likelihood method. The coefficients of variation for growth‐related traits such as body length (BL), abdominal length (AL), and body weight (BW) were 9.36%–22.44%, 10.61%–21.92%, and 26.47%–58.33%, respectively, at different ages (45, 75, 105, 135, and 165 days). The corresponding heritability estimates for each growth trait were 0.1545–0.1951, 0.1672–0.1905, and 0.1596–0.1934, respectively, all of which were found to be at moderate levels and increased with age. The heritability of survival on day 165 was low (0.003). The genetic correlations among growth traits were positive and high (0.7316–0.9896) at the different ages, suggesting that selection to improve any single growth trait will cause positive responses in other growth traits examined in M. japonicus. The genetic correlations between growth traits and survival were also positive but low (0.005–0.087), which indicated that only selecting for growth traits may not cause a positive correlated response in the survival of the core population. According to the above results, we suggested that growth and survival traits should be taken as improving targets of breeding in M. japonicus. These results provided reference data for selective breeding and multitrait selection of M. japonicus.  相似文献   

10.
草鱼幼鱼生长性状和肌肉成分的遗传参数估计   总被引:3,自引:2,他引:1  
为了研究草鱼幼鱼阶段生长性状和肌肉成分的遗传改良潜力。随机采集288尾人工繁育的4月龄草鱼幼鱼,基于12对微卫星标记,鉴定出来自16个家系(8个母本,9个父本)的273尾个体,各家系、母本和父本对应子代贡献率存在极显著差异(P<0.01)。对草鱼3个生长性状(体质量、体长和肥满度)和2个肌肉成分指标(粗蛋白含量和粗脂肪含量)比较发现,3个生长性状和粗蛋白含量在家系和母系半同胞间存在显著差异(P<0.05),而3个生长性状和2个肌肉成分指标在父系半同胞间差异均不显著(P>0.05)。基于动物模型和限制性最大似然法,草鱼4月龄体质量、体长、肥满度、粗蛋白含量和粗脂肪含量的遗传力估值分别为0.34、0.33、0.17、0.17和0.20,其中3个生长性状遗传力估值统计检验显著(P<0.05)。遗传相关分析显示,体质量与体长之间呈极显著的高度正相关(0.82, P<0.01),肥满度与体质量和2个肌肉成分之间存在显著的正相关(0.17-0.29, P<0.05)。研究表明,草鱼4月龄生长性状具有较高的选育潜力,并可通过体长选择实现对体质量的遗传改良;推测在草鱼生长改良过程中,可能会伴随肥满度和粗脂肪含量的变化,这应当引起重视。  相似文献   

11.
Hybrid striped bass fingerlings were grown in replicated indoor tanks for 42 days to evaluate progeny performance of two growth-related traits. Analysis of variance demonstrated significant differences in length and weight of fingerlings among paternal and maternal half-sib families and high estimates of heritability for dams and sires. Based on significant sire and dam effects and high heritabilities, a substantial portion of the selection differential could be expected to be gained in offspring from selected pure-line parents. As demonstrated by these results, a breeding program could be used to select parental lines that produce faster growing hybrid offspring.  相似文献   

12.
应用重复力模型估计虹鳟生长性状的遗传力和育种值   总被引:6,自引:0,他引:6  
采用单性状重复观测值动物模型(重复力模型)对中国水产科学研究院黑龙江水产研究所渤海冷水性鱼类试验站5个品系后代的4026尾虹鳟 (Onchorynchus mykiss) 的生长性状(体重、体长和肥满度)进行了遗传参数和育种值的估计,并对各个性状的表型和遗传趋势进行预测。在此模型中考虑了年份-季节固定效应、父本固定效应和母本固定效应;随机效应有个体的加性效应和个体永久环境效应。结果表明:该5个品系虹鳟及后代体重的遗传力为0.35,体长为0.10、肥满度为0.34。个体间的育种值差异较大,仅排名前20位相差近10倍;从不同评定方法的秩相关来看,用综合育种值法与单个性状方法之间存在极显著的相关,其相关度分别为0.998, 0.877, 0.85. -0.071, -0.064和-0.13。用综合育种值对虹鳟个体的选择价值的评定和名次排列, 以及与单个性状的评定名次有着一定程度上的差别。体重、体长和肥满度性状,其表型趋势与遗传趋势基本一致的品系,均可通过表型值进行选择。  相似文献   

13.
不同生长时期黄姑鱼形态性状对体质量的影响效果分析   总被引:1,自引:0,他引:1  
研究了2月龄和18月龄不同生长阶段的黄姑鱼体质量等9个表型性状的相关关系,采用通径分析方法计算了以体质量为依变量,其他性状为自变量的通径系数和决定系数,并对线性方程加以回归。结果表明,不同的生长阶段体质量的变异系数均为最大;2月龄的全长(0.576)与18月龄的体高(0.558)对体质量的直接作用最大,2月龄的全长与躯干长共同(0.4250)和18月龄的体高(0.3114)是决定体质量的主要性状;通过逐步回归分析方法,经偏回归系数显著性检验,建立了体质量为因变量,2月龄黄姑鱼的最优线性回归方程:y=-0.964+0.724x4+0.289x1(r2=0.957);18月龄黄姑鱼的最优线性回归方程:y=-600.412+54.162x7+18.03x1(r2=0.943);如果在这两个生长阶段对黄姑鱼进行性状选择育种,可以重点根据全长、躯干长、体高性状进行选择育种,对体质量进行间接选择育种,从而保证选择育种的效果。  相似文献   

14.
Asian sea bass (Lates calcarifer) is one of the most important marine food fish species in Asia and Australia. To estimate the reproductive success of broodstock and heritabilities of growth‐related traits, two independent full‐factorial crosses (PI and PII) were created by crossing 10 males and 10 females. At 90 days post hatch (dph), the body weight (BW) and total length (TL) of 804 individuals from PI and 900 individuals from PII were measured and tissues samples of each fish were collected. Parents and offspring were genotyped with nine polymorphic microsatellites. Out of 1704 offspring from the two crosses, 98.7% were assigned to their parents. In PI, 19 of 20 parents produced offspring, while in PII, only five parents contributed to offspring. Low contribution of parents to offspring could lead to reduced genetic variation in the next generation. Heritabilities for growth‐related traits were estimated using the pedigrees reconstructed using microsatellite genotypes. The estimates of heritability were 0.22±0.16 and 0.25±0.18 for BW, 0.31±0.14 and 0.24±0.21 for TL and 0.22±0.22 and 0.15±0.09 for Fulton's condition factor in the two crosses respectively. Body weights at 90 dph and at harvest (289 dph) were significantly correlated (r=0.601, P<0.01). Therefore, growth‐related traits could be improved by exploiting additive genetic effects through selective breeding, and broodstock candidates could be selected early in the production cycle.  相似文献   

15.
Abstract – Understanding how maternal and ova traits influence offspring quality is a key issue in both ecological research and fish culture. We examined the survival and size at hatch of walleye embryos in relation to a suite of maternal and ova traits in laboratory incubation trials involving two native walleye populations. Ova were analysed for size, lipid content, fatty acid composition, soluble protein content and size composition, and mineral (Ca, Co, Cu, Fe, Mg, Mn and Zn) content. Embryonic survival (egg hatching success) varied most consistently with respect to spawning date and maternal age. Embryonic survival increased with maternal age, but other indices of maternal health, such as condition (residual mass at length) or somatic lipid content, did not account for significant amounts of variation. Indices of ova total lipid content, fatty acid composition and mineral composition explained significant variation in embryonic survival not accounted for by maternal age and spawning date, whereas indices of protein content and composition generally explained less variance. Both larval mass and length at hatch were primarily determined by ovum size, but length at hatch was also related to some aspects of ova fatty acid and mineral composition.  相似文献   

16.
红鲤生长性状的上位性遗传效应分析   总被引:8,自引:0,他引:8       下载免费PDF全文
运用加性-显性-上位性遗传模型及其分析方法,研究了兴国红鲤(Cyprinus carpiovar.singuonensis)、荷包红鲤(C.carpiovar.wuyuanensis)和瓯江彩鲤(C.carpiovar.color)的双列杂交子二代F2的体质量和10个形态性状(全长、体长、体高、体宽、头长、吻长、眼径、眼间距、尾柄长和尾柄高)的上位性遗传效应。结果表明,除体高外,其余性状均存在不同程度的加性×加性上位性方差,其中体质量、全长、体长、头长、吻长和尾柄长的加性×加性上位性方差达显著水平(P<0.05);这10项性状的上位性方差占总遗传变异量的百分率为:体质量11.4%、全长22.6%、体长14.0%、体宽8.3%,头长24.2%、吻长17.5%、眼径12.9%、眼间距23.1%、尾柄长5.4%和尾柄高20.1%;通过3种红鲤亲本的遗传育种效应预测发现,瓯江彩鲤的加性和上位性效应能显著增加后代的体质量、全长和体长,而兴国红鲤和荷包红鲤的加性和上位性效应能显著降低后代的体质量、全长和体长。上位性遗传效应在鱼类数量性状的遗传育种中具有较重要作用。[中国水产科学,2006,13(4):573-578]  相似文献   

17.
Genetic parameters and genotype by rearing density interactions for growth traits and survival were investigated in Litopenaeus vannamei. A total of 3626 shrimps from 40 families in two densities (low density, 80 shrimps m?2; high density, 160 shrimps m?2) were measured for four growth traits, body length, body weight, cephalothorax length and abdominal segment length. Variance components and genetic parameters for growth and survival were estimated using a two‐trait animal model or a threshold (probit) sire and dam model. The common environment effect was excluded because it could not be partitioned effectively, likely because of high heritability. The heritability for growth traits varied from 0.21 to 0.44, indicating a moderate level. For survival, the back‐transformed heritability () was 0.36 ± 0.06 and 0.22 ± 0.04 for the low and high densities respectively. There were no significant differences in heritability for growth traits and survival between the two densities (P > 0.05). High genetic correlations (0.94–0.98) between the two densities for growth traits indicated a low genotype by density interaction and ranking effect across the environments, which suggested that these traits were controlled mostly by the same genes over the two densities. Therefore, selection in a low‐density environment should produce desired correlated responses for growth at a high density. Genetic correlation (0.77 ± 0.09) between the two densities for survival was moderate and significant, which indicated that the genotype by density interaction effect was moderate and low for survival under the two densities. Our results provide crucial information for use in L. vannamei breeding programmes in China.  相似文献   

18.
大菱鲆25日龄3个经济性状的遗传参数评估   总被引:7,自引:1,他引:6  
为估计我国引进大菱鲆群体的遗传学参数,2006年从多个大菱鲆养殖场采集源于不同国家和地区、不同进口批次的大菱鲆亲鱼,利用人工授精技术构建了66个全同胞家系,包括26个父系半同胞家系组。选用混合模型方程,通过约束最大似然法进行了方差、协方差、遗传力和遗传相关等估计。结果表明,大菱鲆25d仔鱼体长、存活率和白化率的遗传力分别为0.20、0.07和0.22;3个性状间呈负遗传相关关系,检验不显著。研究结果表明,大菱鲆体长和白化率是中度遗传力,选择育种潜力较大;3个性状任何性状的选择对其他两个性状的影响很小,利用一个性状对另一个性状的间接选择是不可行的。  相似文献   

19.
大黄鱼选育子二代生长性状研究   总被引:2,自引:0,他引:2  
通过对选育和未选育2个群体大黄鱼(Larimichthys crocea)繁育得到的子代的卵径、油球径和口径进行测量,以及对其子代养殖过程中的生长性状进行测量比较,分析选育效果。结果显示,选育大黄鱼子代(XY-F2)和未经选育大黄鱼子代(HB-F1)平均卵径、平均油球径和平均口径之间差异不显著(P〉0.05)。拟合1~10月龄XY-F2和HB-F1的体长(x)、体质量(y)的生长曲线及体长(x)与体质量(y)的关系表明,两群体间体长(x)与体质量(y)的关系存在差异;XY-F2在体长(x)和体质量(y)的生长在后期高于HB-F1。分析其数量性状,选育子一代(XY-F1)2龄鱼体长、体质量现实遗传力分别为0.26、0.18,而XY-F2的体长、体质量现实遗传力分别为0.029、0.134。结果说明选育具有一定的作用,今后选育应该结合家系选择和家系内选择进行。  相似文献   

20.
A 10 × 10 factorial mating design was used to examine the genetic effects on various carcass‐quality traits in hybrid striped bass (Morone chrysops♀×Morone saxatilis♂). A total of 448 offspring were raised in a ‘common‐garden’ environment and carcass‐quality traits were assessed at 389 days post fertilization; parentage of each fish was inferred from genotypes at 5–10 nuclear‐encoded microsatellites. There was a significant effect of dam and sire on body weight and fillet weight and a significant effect of dam on viscera weight and condition factor. When carcass‐quality traits were standardized to body weight, there was a significant effect of dam, sire and dam × sire interaction on viscera percentage (proportion of viscera weight to body weight). Phenotypic correlations between body weight and non‐standardized carcass‐quality traits were high (rp=0.80–0.92), whereas phenotypic correlations between body weight and standardized carcass‐quality traits were low (rp=0.13–0.19). Genetic correlations between body weight and fillet weight (dams and sires), and body weight and viscera weight (dams only) were significant and positive, while the genetic correlations between body weight and viscera percentage (dams and sires) were significant and negative. Significant general combining ability values for favourable carcass‐quality traits in the same breeder (dam or sire) occurred only in one or two of 20 (dams and sires) used in this study, suggesting that simultaneous improvement in multiple traits in hybrid striped bass may require evaluation of large numbers of candidate breeders. The effect of sex on body weight and all non‐standardized carcass‐quality traits was significant and appeared to be due to faster growth in females. These results indicate that selection for faster growth of hybrid striped bass would lead to a correlated increase in fillet weight and viscera weight but not necessarily to an increase in the proportion of fillet and waste product generated. The significant dam, sire and dam × sire interaction effects on viscera percentage and the negative genetic correlations between body weight and viscera percentage indicate that selection for reduced proportion of viscera relative to body weight might be feasible.  相似文献   

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