【作者】 刘永新；

【导师】 刘海金；

【作者基本信息】 东北农业大学 ， 动物营养与饲料科学， 2009， 博士

【摘要】 牙鲆是我国海产名贵经济鱼类,其人工养殖始于20世纪90年代,目前已发展成为北方和福建沿海的重要养殖对象。但是所养殖的牙鲆无品种可言,繁殖亲本主要来自海捕野生鱼或经过数代养殖的野生鱼,没有经过人工选育,其子代生长速度较慢,抗病力差,适应集约化养殖能力较弱。因此,开展其遗传改良研究,培育生长速度快等经济性状良好的牙鲆优良家系对于保护牙鲆自然资源和满足当前养殖业的迫切需要具有极其重要的意义。本文以中国水产科学研究院北戴河中心实验站牙鲆选育家系为研究对象,采用非求导约束极大似然法(DRFEML)对不同动物模型估计的体重、体长、体高、体型等生长性状的遗传参数差异进行了比较;利用动物模型BLUP方法估计不同日龄体重、体长、体高的单性状育种值和综合育种值,并对不同家系进行比较;利用微卫星分子标记分析牙鲆雌核发育家系,及其与体重、体长、体高的相关性;根据牙鲆生长激素基因序列设计引物,采用直接测序法对牙鲆生长激素基因进行单核苷酸多态检测,并对其进行与体重、体长、体高的关联分析。研究结果如下:(1)固定效应分析结果中,家系年份对不同日龄体重、体长、体高、体型具有极显著影响(P<0.01);生殖方式对180日龄生长性状,240日龄体长、体型,360日龄体重、体长、体型有显著影响(P<0.05),对240日龄体重、体高,360日龄体高无显著影响(P>0.05)。比较了4种动物模型估计不同日龄体重、体长、体高、体型遗传参数的差异,结果表明:模型Ⅳ适合估计体重、体长、体高,模型Ⅲ适合估计体型的遗传参数。(2) 180日龄体重、体长、体高、体型的遗传力分别为0.35、0.30、0.35、0.25。240日龄体重、体长、体高、体型的遗传力分别为0.30、0.32、0.39、0.25。360日龄体重、体长、体高、体型的遗传力分别为0.13、0.29、0.37、0.30。不同日龄体重与体长、体重与体高、体重与体型存在较强的正向遗传相关,其遗传相关范围分别为0.80-0.96、0.89-0.97、0.76-0.89;体长与体高、体长与体型存在很强的正向遗传相关,其遗传相关范围分别为0.88-0.94、0.95-0.99;体高与体型存在较强的负向遗传相关,其遗传相关范围为-0.69--0.76。(3)对于180、240日龄体重、体长、体高和360日龄体长、体高,家系根据单性状育种值和综合育种值进行遗传评定的结果基本相同;对于360日龄体重,家系根据单性状育种值和综合育种值进行遗传评定结果存在一定差异。四种遗传评定方法的秩相关分析结果达到了极显著水平(P<0.01)。体重、体长、体高在不同日龄的遗传和表型趋势均呈上升趋势。(4)对不同日龄生长性状育种值选择和表型值选择效率进行比较。结果表明,不同日龄生长性状依据育种值选择与依据表型值选择的结果存在较大差异。在360日龄,两种选择方法之间的差异达到最小,依据育种值选留的家系和个体比依据表型值选留的家系和个体分别提高:体重,93.92%和28.97%;体长,465.22%和124.49%;体高,176.00%和157.80%;育种值选择效率明显高于表型值选择效率。(5)微卫星分析结果表明:有8个微卫星座位与体重、体长、体高显著相关,poli6TUF、poli30TUF、poli116TUF、poli145TUF与体重、体长显著相关(P<0.05);poli107TUF、poli108TUF、poli123TUF与体长显著相关(P<0.05);poli9-8TUF与体重、体长、体高显著相关(P<0.05)。对同一标记不同基因型间进行多重比较,找到与性状相关的基因型。(6)以牙鲆雌核发育家系为材料,根据牙鲆生长激素基因序列设计了14对引物,其中6对引物扩增可用,共扩增出总长1736bp的序列。采用直接测序法对牙鲆生长激素基因编码区和启动子区进行了单核苷酸多态检测(SNPs)。在所测序的1736bp的序列中共检测到10个SNPs,并进行与生长性状的关联分析。结果表明:2067T/-del和C477T两个位点对体重、体长、体高的影响达到显著水平(P<0.05),其它SNP位点对生长性状的影响不显著(P>0.05)。更多还原

【Abstract】 The Japanese flounder is marine precious economical fishes in China, the artificial cultivation of Japanese flounder began from the 1990s, nowadays it has been the the most important breeding species throughout the north and FuJian coastal areas. Despite this, most of the production is carried out using unselected breed. The broodstock mainly come from wild fish captured in the sea or under several generations cultured. The offspring take on slow growth rate, poor resistance to disease and weak ability of adap to intensive breeding. Therefore the development of genetic improvement study and the cultivation of excellent family of Japanese flounder of good economic traits such as fast growth have very important meaning to protect the natural resource and meet the current needs of aquaculture industry. Samples were obtained from BeiDaiHe center lab station of the Chinese Academy of Fishery Science, based on the selection and breeding families of Japanese flounder, and used derivative free restricted maximum likelihood (DFREML) to compare the difference of genetic parameters of growth traits including body weight (BW), body length (BL), body depth (BD) and body shape (BS) estimated by different animal models. Single trait and integrative breeding value of different day-age BW, BL and BD were estimated by animal model best linear unbiased prediction (BLUP), furthermore different families were compared. Gynogenesis families of Japanese flounder were studied by microsatellite DNA marker, analyzed its correlation with BW, BL and BD. Primers were designed on the basis of Japanese flounder growth hormone gene sequence. Single nucleotide polymorphisms (SNPs) were detected by direct sequencing for Japanese flounder growth hormone gene, furthermore analyzed its correlation with BW, BL and BD. The results showed:(1) The analytic results of fixed effect showed that the family year had extremely significant effect on different day-age BW, BL, BD and BS (P<0.01). Reproduction method had significant effect on 180 day-age BW, BL, BD, BS, 240 day-age BL, BS and 360 day-age BW, BL, BS (P<0.05), but had no significant effect on 240 day-age BW, BD and 360 day-age BD (P>0.05). The differences of genetic parameters of different day-age BW, BL, BD, BS estimated by 4 animal models were compared. The results showed that modelⅣwas fit to estimate genetic parameters of BW, BL and BD, modelⅢwas fit to estimate that of BS.(2) Heritabilities for 180 day-age BW, BL, BD and BS were 0.35, 0.30, 0.35 and 0.25. Heritabilities for 240 day-age BW, BL, BD and BS were 0.30, 0.32, 0.39 and 0.25. Heritabilities for 360 day-age BW, BL, BD and BS were 0.13, 0.29, 0.37 and 0.30. The range of different day-age high positive correlations between BW and BL, BW and BD, BW and BS was 0.80-0.96, 0.89-0.97, 0.76-0.89, respectively. The different range of very high positive correlations between BL and BD, BL and BS was 0.88-0.94, 0.95-0.99, respectively. The different range of high negative genetic correlations between BD and BS was -0.69--0.76.(3) There was no difference in the results of genetic evaluation according to single trait and integrative breeding value of 180, 240 day-age BW, BL, BD and 360 day-age BL and BD in families. There was a little difference in the results of genetic evaluation according to single trait and integrative breeding value of 360 day-age BW in families. Rank correlation analysis of four methods of genetic evaluation reached extremely significant level (P<0.01). Phenotypic and genetic trend at different day-age for BW, BL and BD showed rising trend.(4) The comparison of selection efficiency based on breeding value or phenotypic value showed that there was significant difference in the selection based on breeding value or phenotypic value for different day-age growth traits. The minimum difference in both selection methods was observed in the 360 day-age. The efficiency of breeding value selection was found to be 93.92% and 28.97% of BW, 465.22% and 124.49% of BL, 176.00% and 157.80% of BD higher than that of phenotypic value selection for family or individual, the efficiency of breeding value based selection was significant higher than that of the phenotypic selection.(5) The results of microsatellite analysis showed that 8 microsatellite markers were significant correlation with BW, BL and BD. The poli6TUF, poli30TUF, poli116TUF and poli145TUF had significant correlation with BW and BL (P<0.05), poli107TUF, poli108TUF, poli123TUF had significant correlation with BL (P<0.05), poli9-8TUF had significant correlation with BW, BL and BD (P<0.05). Different genotypes of the same marker were multi-ply compared and found correlation with traits.(6) The materials were from Japanese flouner gynogenesis families. 14 pairs of primer were designed according to Japanese flounder growth hormone gene sequence, in which six pairs of could be useful and the total of 1736bp sequence was amplified. SNPs were detected in coding and promoter region by direct sequencing. 10 SNPs was identified in a fragment of the growth hormone gene spanning 1736bp and the correlation analysis with growth traits was carried out. The results showed: the effect of 2067T/-del and C477T loci on the BW, BL and BD reached significant level (P<0.05). The other SNPs loci have no significant effect on growth traits (P>0.05).更多还原