The effect of interstrain hybridization on the production performance in the Pacific oyster Crassostrea gigas

Effect of inbreeding on performance and genetic parameters of growth and survival traits in the Pacific oyster Crassostrea gigas at larval stage

The Pacific oyster Crassostrea gigas is a representative bivalve mollusc that is widely cultured in the world and is the largest molluscan group cultured in China. In order to assess the feasibility of improving survival of C. gigas through genetic selection, the heritability and genetic correlations for growth and survival traits between different life stages were examined. Genetic parameters were estimated based on intraclass correlations of 49 full-sib families (29 half-sib families) in larvae (4 and 20 days after fertilization) and spat (140 days after fertilization) stages. The heritability for growth traits in larvae and spat was 0.30–0.86 and 0.53–0.59, respectively, and varied with ages. The heritability of survival was low in larvae (0.13 ± 0.05 and 0.17 ± 0.04, respectively for 4 and 20 days after fertilization) but medium (0.39 ± 0.07) in spat, suggesting that selection for increasing spat survival was feasible. The genetic correlation between growth traits within age was medium to high and positive (ranging from 0.47 to 0.96, respectively, between shell length (SL) and shell height (SH) at 20 days and between SL and SH at 140 days after fertilization), suggesting that selection to improve single growth trait will cause positive response in another growth traits in C. gigas. The genetic correlations between survival and growth traits at 140 days were low but positive (ranging from 0.23 to 0.27, respectively, between survival and SH and between survival and SL at 140 days after fertilization), suggesting that selection for survival may not have a negative response in growth. Overall, this study suggests that survival traits should be taken as improving target of next selection breeding programme in C. gigas.

The DNA methylation level is associated with the superior growth of the hybrid crosses in the Pacific oyster Crassostrea gigas

PDF HTML阅读 XML下载 导出引用 引用提醒 壳白长牡蛎品系生长和壳色性状遗传参数估计 DOI: 作者: 作者单位: 中国海洋大学, 海水养殖教育部重点实验室, 山东 青岛 266003 作者简介: 邢德(1992-),男,硕士研究生,从事贝类遗传育种研究.E-mail:xingzhidezhi@126.com 通讯作者: 中图分类号: S917 基金项目: 国家自然科学基金项目（31372524）；泰山学者种业计划专家项目；山东省科技发展计划项目（2016ZDJS06A06）. Estimates of genetic parameters for growth and shell color traits in the white-shell strain of Pacific oyster (Crassostrea gigas) Author: Affiliation: The Key Laboratory of Mariculture, Ministry of Education;Ocean University of China, Qingdao 266003, China Fund Project: 摘要 | 图/表 | 访问统计 | 参考文献 | 相似文献 | 引证文献 | 资源附件 | 文章评论 摘要:以经过连续4代家系选育获得的壳白长牡蛎（）选育系为亲本，通过巢氏平衡设计建立了30个全同胞家系混合养殖，采用微卫星多重PCR技术进行家系鉴定，基于REML法估算24月龄壳白长牡蛎的生长性状和壳色性状的遗传参数。结果表明，壳白长牡蛎品系壳高、壳长、总重、壳重、（黄蓝轴色品指数）的遗传力为中高等水平，依次为0.35±0.13、0.18±0.09、0.20±0.09、0.16±0.08、0.16±0.08、0.27±0.11和0.19±0.08，壳宽、肉重、出肉率、壳型指数的遗传力为低等水平，依次是0.07±0.02、0.11±0.06、0.02±0.03、0.08±0.06和0.11±0.06。壳高、壳长、壳宽、总重、壳重和肉重之间的遗传相关和表型相关均为正相关，其中，壳高、壳宽和总重与其他生长性状的相关性较高，分别为0.40±0.65~0.90±0.14、0.39±0.55~0.97±0.24和0.50±0.66~0.99±0.02。壳型指数与壳高均为较高的负相关，分别为-0.94±0.16和-0.77±0.19，表明仅以壳高性状为选育目标时，可能不会对长牡蛎壳型改良产生作用。壳白长牡蛎壳色参数与生长性状之间的遗传相关范围为-0.09±0.42~0.91±0.74，不同性状间的遗传相关差异很大，其中*任一个为选育目标时，其他生长性状都可以获得提高。壳色参数间与相关性较低，分别为-0.08±0.36和0.21±0.31，表明以值。本研究为合理制定壳白长牡蛎新品系育种方案和选择反应预测提供了参考依据。 Abstract:The Pacific oyster () is the most widely cultured shellfish in the world. There is considerable focus on improving selective breeding procedures for economic traits. We used specimens of the white-shell strain of after four generations of family selection as parents to construct 30 full-sib families in a nested design. A mixed family approach combined with parentage analysis using highly polymorphic microsatellite makers and REML based on the animal model was used to estimate genetic parameters of white-shell at the age of 24 months. The results showed that heritabilities of shell height, shell length, total weight, shell weight, were 0.35±0.13, 0.18±0.09, 0.20±0.09, 0.16±0.08, 0.16±0.08, 0.27±0.11, and 0.19±0.08, respectively. Shell width, meat weight, meat ratio, and indexes of shell shape showed lower heritabilities of 0.07±0.02, 0.11±0.06, 0.02±0.03, 0.08±0.06, and 0.11±0.06, respectively. All phenotypic and genetic correlations among shell height, shell length, shell width, total weight, shell weight, and meat weight were positive. Genetic correlations were higher between shell height, shell length, total weight, and the other growth traits, ranging from 0.40±0.65 to 0.90±0.14, 0.39±0.55 to 0.97±0.24, and 0.50±0.66 to 0.99±0.02, respectively. Genetic correlation between index A of shell shape and shell height was -0.94±0.16, and -0.77±0.19 between index B of shell shape and shell height, suggesting that shell shape would not change if just shell height were selected in breeding programs. Genetic correlations were significantly different between shell color traits and growth traits, varying from -0.09±0.42 to 0.91±0.74. Higher genetic correlations between * (the same as shell height, shell length, and total weight) could improve other growth traits. There was a negative genetic correlation between of -0.96±0.04. Conversely, genetic correlations were lower between and could also decrease . This information will benefit genetic improvement of the white-shell strain of . 参考文献 相似文献 引证文献

The Pacific oyster Crassostrea gigas has been introduced widely and massively and became an economically important aquaculture species on a global scale. We estimated heritabilities of growth and shell color traits and their genetic correlations in black shell strain of C. gigas. Analyses were performed on 22 full-sib families in a nested mating design including 410 individuals at harvest (24months of age). The parentage assignment was inferred based on four panels of multiplex PCR markers including 10 microsatellite loci and 94.9% of the offspring were unambiguously assigned to single parent pairs. The Spearman correlation test (r=-0.992, P<0.001) demonstrated the high consistency of the shell pigmentation (SP) and L* and their same efficacy in shell color measurements. The narrow-sense heritability estimated under the animal model analysis was 0.18±0.12 for shell height, 0.25±0.16 for shell length, 0.10±0.09 for shell width, 0.42±0.20 for total weight, 0.32±0.18 for shell weight, and 0.68±0.16 for L*, 0.69±0.16 for shell pigmentation, respectively. The considerable additive genetic variation in growth and shell color traits will make it feasible to produce genetic improvements for these traits in selective breeding program. High genetic and phenotypic correlations were found among growth traits and among shell color traits. To optimize a selection strategy for both fast growth and pure dark shell strain of C. gigas, it is proposed to take both total weight and black shell as joint objective traits in selective breeding program. Our study offers an important reference in the process of selective breeding in black shell color stain of C. gigas and will facilitate to develop favorable breeding strategies of genetic improvements for this economically important strain.

The basic helix-loop-helix (bHLH) genes encode a large superfamily of transcription factors in the Pacific oyster (Crassostrea gigas), and play a very important role in regulation of growth and development. To investigate the oyster growth traits and the associations with bHLH genes variations, we analyzed the gene polymorphisms-traits association in a wild population, and confirmed the results in another independent wild population by targeted gene re-sequencing and SNPshot analysis. After screening the single nucleotide polymorphisms (SNPs) in three candidate genes of the bHLH family (88 bHLH genes in two wild oyster populations in total), we identified the allele CgLoblHLH4-T/G located in the exon of the CgLoblHLH4 gene. This allele is a non-synonymous mutation (Phe/Leu) with an extremely significant association with shell width (P<0.01) and allele G is beneficial to shell width. This SNP on the CgLoblHLH4 gene might have a potential value as a genetic marker of growth traits that could be used in breeding in C. gigas in the future.

Polymorphism in the insulin-related peptide gene and its association with growth traits in the Pacific oyster Crassostrea gigas

Introduction and evaluation on the US West Coast of a new strain (Midori) of Pacific oyster (Crassostrea gigas) collected from the Ariake Sea, southern Japan

Heterosis and genetic diversity of intraspecific hybrids crosses between two selected lines of the Pacific oyster Crassostrea gigas

Genetic and phenotypic parameter estimates for measurement traits were obtained from pacific oyster Crassostrea gigas at nine months old. For the growth-related traits among nine months old pacific oyster, heritabilities of shell length, shell height, shell width, total weight, body weight and shell weight were estimated as 0.4855, 0.5248, 0.0884, 0.7236, 0.7726 and 0.6957, respectively. Genetic correlations among the growth-related traits of pacific oyster at nines month old, shell length, shell height, shell width, total weight, body weight, shell weight were showing highly positive correlations. Breeding value on growth-related traits of pacific oyster at nine months old were estimated as shell length -7.044-11.870, shell height -11.380-18.370, shell width -1.234-2.831, total weight -8.339-17.140, body weight -1.813-3.507 and shell weight -4.422-8.837. The results show that there is quite substantial additive genetic variance for measurement traits in pacific oyster that can be exploited through selective breeding.

The Pacific oyster Crassostrea gigas is one of the most commercially important and worldwide cultured fishery animals. To facilitate marker-assisted selection in genetic improvement of this species, 108 novel polymorphic single-nucleotide polymorphism (SNP) markers were developed from expressed sequence tags (ESTs) by high-resolution melting analysis. The association between the markers and growth traits in a fast-growing strain and validation in two cultured populations was analyzed. For the 108 SNP loci, the observed heterozygosity varied from 0.011 to 0.625 and the expected heterozygosity varied from 0.031 to 0.501. By selective genotyping method, special allele frequencies of nine SNP markers showed significant difference between the fast-growing strain and the commercial control population (P < 0.0001). The nine SNP loci were further validated in extreme phenotype tails of the commercial control population and an independent cultured population. Three markers, jl027, ji090, and jl615, were found to be significantly associated with growth traits in oysters (P < 0.01). The proportion of additive genetive variance explained by the three confirmed SNPs ranged from 0.27 to 2.23%. The putative functions of the ESTs containing the jl090 and jl615 markers indicated that they might be related to growth of C. gigas. The three confirmed SNPs associated with growth traits would have potential applications in future genetic improvement of C. gigas.

Selective breeding for summer survival in Pacific oyster (Crassostrea gigas): Genetic parameters and response to selection

Genome-wide analysis of the cytochrome P450 gene family in Pacific oyster Crassostrea gigas and their expression profiles during gonad development

64. Comparative cryopreservation study of trochophore larvae from two species of bivalves: Pacific oyster (Crassostrea gigas) and blue mussel (Mytilus galloprovinciallis)

First report of a putative involvement of the NMDA pathway in Pacific oyster (Crassostrea gigas) development: Effect of NMDA receptor ligands on oyster metamorphosis with implications for bivalve hatchery management