Expression profiles of sex-related genes in gonads of genetic male Takifugu rubripes after 17β-estradiol immersion

Estradiol treatment during early life stages of tiger puffer Takifugu rubripes induces feminization in genetic males.However,the ovaries in genetic males may revert to testes once estradiol treatment is halted.Therefore studies should investigate molecular mechanisms underlying ovary-to-testis recovery in genetic males after treatment.In the present study,tiger puffer were exposed to 10,and 100μg/L 17β-estradiol(E 2)from 15 to 100 days post-hatching(dph),then gonad phenotypes and expression profi les of six sex-related genes(cyp19a,foxl2,dmrt1,amh,sox9a,and sox9b)were characterized after the exposure.Results showed that both 10 and 100μg/L E2 induced ovarian development in genetic males at 100 dph.However,all ovaries induced by 10μg/L E2 first developed into intersexual gonads and subsequently reverted to testes after the exposure.As for treatment of 100μg/L E2,while the rest of the ovaries maintained morphological stability,percentages of intersexual gonads reached 38%-57%,and none were reverted to testes.Increased mRNA levels of cyp19a,foxl2 and sox9b and decreased mRNA levels of dmrt1,amh,and sox9a were observed during the ovarian development in genetic males.While contrary gene expression profiles were detected during ovary-to-testis transformation.The mRNA levels of all the six genes were increased during the development of intersexual gonads.These results indicated that up-regulation of dmrt1,amh and sox9a is associated with initial ovary-to-intersexual transformation,and suppression of foxl2,cyp19a and sox9b is essential for complete ovary-to-testis recovery in genetic males.This research will help to trace the molecular processes underlying gonadal transformation in teleosts.     

亚硝酸氮对红鳍东方[鱼屯]的毒性效应

采用半静水生物测试法,研究亚硝酸盐氮对红鳍东方[鱼屯]（Takifugu rubripes）（95～9．8g）的急性毒性及对部分肝脏抗氧化酶活性的影响。结果表明,在急性毒性实验中,亚硝酸盐氮对红鳍东方[鱼屯]的24、48、72和96h半致死质量浓度（LC50）分别为20188、19057、17109、15925mg／L,安全质量浓度为1592mg／L;在亚急性毒性实验中,当红鳍东方纯分别在5．3、106,159、212mg／L亚硝酸盐氮中暴露4周时,其肝脏总抗氧化能力（T—AOC）、超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性随亚硝酸盐氮浓度的升高均被显著抑制,差异有统计学意义（P〈0.05）,表明亚硝酸盐氮会对鱼体的抗氧化能力产生影响。     

红鳍东方鲀(Takifugu rubripes)选育家系构建与早期标准化培育

采用巢式设计方法和人工受精技术, 对红鳍东方鲀(Takifugu rubripes)选育家系的构建与标准化培育技术进行研究。按照1雄配2雌的原则, 选取养殖、野生和日本3个群体的红鳍东方鲀进行定向交配, 并对红鳍东方鲀早期阶段苗种进行了环境标准化和一、二、三、四级数量标准化培育。结果表明, 红鳍东方鲀亲鱼产卵量大, 对构建父系半同胞家系十分有利; 从4次数量标准化看, 每次各家系内鱼苗数量都较为集中, 各阶段各家系的成活率也较高, 但存在部分家系间数量差异显著; 经过4次数量标准化, 成功构建22个父系半同胞家系, 48个母系全同胞家系。对早期阶段家系构建和培育存在的问题, 进行了探讨并提出拟解决方法, 为大规模建立红鳍东方鲀家系提供参照。     

中国东方鲀属鱼类一新种——晕环东方鲀

在1979年7月—1981年11月间,在长江口采集到24尾体长为32—214mm的东方鲀属鱼类标本,经形态特征和解剖比较研究后,认为是一新种,定名为晕环东方纯Takifugu coronoidus Ni et Li nov. sp.。正副模式标本存放于中国水产科学研究院东海水产研究所和中科院海洋研究所。     

暗纹东方鲀生长性状相关微卫星标记筛选

为了筛选与暗纹东方鲀(Takifugu obscurus)生长相关的分子标记,作者采用SSR结合BSA技术对同龄孵化群体的同池养殖暗纹东方鲀生长差异性状标记进行筛选。利用85对微卫星引物对暗纹东方鲀生长快、慢各30尾个体构建的两个基因池进行分析,共筛选到14个差异位点。然后分析这14个差异微卫星位点在这60个暗纹东方鲀个体中的基因型差异,结果表明:位点TOP03、TOG01、fms15、fms75与生长性状呈现极显著负相关关系(P0.01),fms89与生长性状呈现极显著正相关关系(P0.01)。用另外30个个体(生长快慢各15个)进行验证实验后,结果只有位点fms15、fms75与生长性状显著相关,相关系数分别为–0.411和–0.384。这两个微卫星位点对于暗纹东方鲀生长性状有显著效应,为开展暗纹东方鲀的分子标记辅助育种提供了有价值的参考标记。     

菊黄东方鲀人工繁殖及育苗技术研究

报道了2004～2005年菊黄东方鲀(Fugu flavidus)人工繁殖及育苗实验结果.在春季当水温达到20℃以上时,用地欧酮(DOM)、促黄体素释放激素类似物(LHRH)或绒毛膜促性腺激素(HCG)进行催产,混和或单一使用,剂量视亲鱼性腺成熟度而定.受精卵在海水盐度20.0～30.0,水温20.0～25.0℃条件下,经144～156 h孵化.608万尾仔鱼培育出平均全长4.43 cm、平均体质量1.98 g的幼鱼168.5万尾,成活率27.7%.对亲鱼的暂养、催产、孵化、仔鱼的前期培育和仔鱼的后期培育等关键技术进行了探讨.     

Temperature-control-induced masculinization in tiger puffer Takifugu rubripes

This study used tiger puffer Takifugu rubripes to explore new,simple methods for lowtemperature-induced masculinization in a cultured fish without the use of ultraviolet irradiation or sex hormones.An orthogonal test L9(3^4)design was used to consider three factors at three levels:treatment starting times(days post-hatch,dph:factor A)of 20,50 and 80 dph;treatment temperatures(factor B)of 13℃,15℃and 17℃;and treatment durations(factor C)of 30,45 and 60 days.A control group was reared at 21±1℃.The experiments were repeated twice.At 230 dph,the gonads were removed from thirty randomly sampled fish in each group.Histological observations and analysis of single nucleotide polymorphisms(SNP)were used to identified pseudo males,which biological sex was male and genetic sex were female(XX).Treatment group 4(A2B1C2)resulted in the highest proportion of males(75%).According to the intuitive analysis of the orthogonal-array experiments,the optimal combination of lowtemperature-induced masculinization of T.rubripes was A2B1C2.The population sex ratio depended on the three factors in the sequence B→A→C.A comparison of the daily increases in length and weight during and after the low-temperature conditions showed that the absolute daily increases in weight and length were significantly less during treatment than after treatment.Daily increases in weight and length did not significantly differ between the treatment groups and the controls(P>0.05),demonstrating that the growth rate could return to normal after the low-temperature conditions.This study establishes a low-temperatureinduced masculinization technology for T.rubripes and demonstrates that although the growth rate(length and weight)decreased in an array of nine treatment groups during the processing time,it returned to a normal level after processing.The results should serve as a guide for achieving the masculinization of T.rubripes in production.     

渤海莱州湾红鳍东方鲀(Takifugu rubripes)×假睛东方鲀(Takifugu pseudommus)天然杂交种一例

记述了１９９８年５月莱州湾中采得的东方（Ｔａｋｉｆｕｇｕ）标本中的２尾个体,其形态特征介于红鳍东方（Ｔａｋｉｆｕｇｕｒｕｂｒｉｐｅｓ）和假睛东方（Ｔａｋｉｆｕｇｕｐｓｅｕｄｏｍｍｕｓ）之间,经比较分析认定其为该两近缘种的天然杂交种     

红鳍东方鲀养殖技术研究现状及展望

<正>红鳍东方鲀(Takifugu rubripes),属鲀形目(Tetraodontiformers)、鲀亚目(Tetraodontoidei)、鲀科(Tetraodontidae)、东方鲀属(Takifugu),俗称河鲀、廷巴、腊头、龟鱼等,为近海底层食肉性鱼类,主要分布于北太平洋西部的日本、朝鲜半岛和中国沿海[1]。因其味道鲜美、肉质细嫩,经济价值高昂,在中国北方地区和日本、韩国等形成养殖规模。目前国内外对红