林麝泌香期性激素变化及其与泌香量的关系

为了检测泌香期雄性林麝分泌的性激素(睾酮、雌二醇和孕酮)的含量,探究其变化规律及与泌香量的关系.利用放射免疫分析法(RIA)检测了2010.04-2011.12间雄性林麝粪样中的性激素水平.结果显示不同年龄段雄性个体的睾酮、雌二醇含量在泌香期均有明显的变化规律.正常期粪样中睾酮含量较低,泌香期前睾酮的含量开始升高,泌香初期睾酮含量急剧升高,显著高于正常期(P＜0.05),泌香盛期睾酮的含量达到最高峰,显著高于其他各个时期(P＜0.05),泌香后期睾酮含量急剧下降,泌香期后继续下降.雌二醇也呈现出与睾酮相似的变化规律,泌香盛期雌二醇的含量也达到最高峰,除了8～10岁雄性林麝的雌二醇含量与泌香期后期差异不显著外,与其他各时期均差异显著(P＜0.05).雄性林麝孕酮的含量在整个泌香期表现出无规律性变化.相关分析表明,林麝的泌香量与整个泌香期睾酮的含量之间呈显著强正相关(R2 =0.650 4,P＜0.05),与雌二醇的含量之间呈显著正相关(R2=0.456 5,P＜0.05).利用粪样来研究半驯养野生动物的性激素是一种较为理想的方法,具有推广与应用价值.     

不同激素组合对人工诱导星康吉鳗性成熟效果的比较

通过分析星康吉鳗(Conger myriaster)人工催熟过程中其外表形态、性腺发育和性类固醇激素含量的变化关系,以期为星康吉鳗的人工繁殖提供数据支撑。实验共收集野生星康吉鳗100尾[(288.30±62.34)g],分为对照组和3个激素注射组:实验组A(CPE:2 mg/kg),实验组B(HCG:200 IU/kg)和实验组C(CPE:1 mg/kg和HCG:100 IU/kg)。每周进行1次激素注射,共注射12次激素,对照组不做处理。结果表明:实验组C亲鱼卵母细胞发育至细胞核移位阶段,星康吉鳗性腺发育状态最佳。完成12次激素注射后,所有的实验组星康吉鳗卵母细胞发育均达到Ⅲ期,而对照组卵母细胞发育仍停滞在第Ⅱ期。通过对类固醇激素进行ELISA检测表明,在第12次注射后,实验组C星康吉鳗性腺中睾酮含量[(217.00±31.76)ng/g]显著高于对照组[(123.24±21.05)ng/g]。与对照组相比,注射激素实验组星康吉鳗性腺中17α-羟基孕酮含量呈现缓慢上升趋势。至实验结束时,CPE和HCG组合激素注射的星康吉鳗性腺发育到第Ⅴ期。综上所述,CPE+HCG能够有效地促进星康吉鳗的性腺发育,可作为催熟激素用于星康吉鳗的人工繁殖。     

半滑舌鳎伪雄鱼性腺发育的组织学研究

[目的]了解半滑舌鳎性逆转的生理发育过程。[方法]对5个家系的半滑舌鳎进行性腺发育的组织学观察、遗传性别鉴定和生理性别分析。[结果]半滑舌鳎性逆转有着明显的群体性,性逆转只发生在特定群体中,有些群体完全不逆转;半滑舌鳎发生逆转的遗传雌鱼在性腺发育过程中,会出现明显的兼性阶段,即雌雄兼有的特有过程。[结论]该研究结果可为剖析半滑舌鳎性逆转的分子、生理机理以及性逆转遗传因子的作用机理提供研究方向和研究线索。     

Investigation into the possible role of androgens in the induction of hepatic vitellogenesis in the European eel:in vivo andin vitro studies

Changes in the levels of plasma vitellogenin (Vg), estradiol (E₂) and testosterone (T) were examined following gonadal development induced by carp gonadotropin treatment (cGTH) of freshwater female yellow and silver eels (Anguilla anguilla L.). The animals received injections of cGTH (250 μg kg⁻¹ body weight) or saline vehicle three times a week, for 6 to 8 weeks. No effect of vehicle was observed. Steroidogenic activity of the ovary was stimulated by cGTH treatment as shown by the increase in circulating steroid levels in both stages. However, the responses of T, E₂ and Vg differed according to the stage of development of eels. At the yellow stage, the initial steroid plasma levels were undetectable (< 0.01 ng ml⁻¹) before treatment and ovarian steroidogenic activity was slightly stimulated following cGTH treatment; steroid levels reached their highest values after 3 weeks and 6 weeks of treatment for E₂ (0.62 ± 0.13 ng ml⁻¹ and T (0.33 ± 0.30 ng ml⁻¹), respectively. The cGTH treatment slightly increased plasma Vg levels (0.2–0.7 μg ml⁻¹ during the experiment compared with the initial values of the group. At the silver stage, the initial steroid levels were detectable (0.7 ng ml⁻¹ for E₂ and 0.1 ng ml⁻¹ for T); cGTH treatment did not significantly increase plasma E₂ level which remained at initial levels. Nevertheless, plasma T levels dramatically increased from 0.1 to 3 ng ml⁻¹ and peaked after 1 or 2 weeks of cGTH treatment; a rapid increase in plasma Vg levels occurred, reaching its highest value at 5 mg ml⁻¹ after 3 weeks of treatment. Thus, the steroid kinetic profiles in relation to the appearance of Vg in the plasma following cGTH treatment was closely related to androgen levels and there was a strong vitellogenic response induced by chronic cGTH treatment. In order to test if androgens could be implicated in the vitellogenic response, we evaluated the potencies of various androgens (testosterone and 5α-androstane-3β,17β-diol)in vivo andin vitro, associated with E₂ to induce the production of Vg.In vitro experiments showed that Vg synthesis was induced by high doses (10⁻⁶ to 10⁻⁵ M) of androgen in the eel. Tamoxifen totally inhibited the action of androgens suggesting that androgens were acting through binding to the E₂ receptor.In vivo, androgens given alone at 50 μg kg⁻¹ 3 times a week for 1 months had no significant effect on plasma Vg levels. In addition, E₂-androgen cotreatment showed that the presence of androgen did not modify the vitellogenic response induced by E₂.     

鲥鱼在中国东南近海生殖洄游期间性腺发育的研究

鲥鱼是名贵的溯河洄游性鱼类,每年春夏之交,沿我国东南近海作生殖洄游,并溯入长江、钱塘江和珠江繁殖。对长江和钱塘江鲥鱼性腺发育的研究,国内已有一些报导,如陆桂等曾记述过钱塘江鲥鱼Ⅳ期和Ⅴ期性腺的外形特征,作者等曾注意过鲥鱼在近海和钱塘江洄游期间的性腺发育。     

Maturation and reproductive cycle of female armorhead <Emphasis Type="Italic">Pseudopentaceros wheeleri</Emphasis> from the southern Emperor—northern Hawaiian Ridge Seamounts

ABSTRACT:   The stage of ovarian development and annual reproductive cycle of female armorhead Pseudopentaceros wheeleri collected from seamounts of the southern Emperor–northern Hawaiian Ridge in 1993 and 1995–1996 was investigated through use of the gonadal somatic index ( GSI ) and ovarian histology. The stages of oocyte development were classified into eight developmental stages (perinucleolus, cortical alveolus, oil droplet, early yolk globule, late yolk globule, migratory nucleolus, prematuration, and maturation) based on histological characteristics. Oocytes of different size and developmental stage were present within ovaries during the spawning season. Oocyte development appears to be asynchronous and armorhead apparently spawn several times during the spawning season. The stage of the most developed oocyte was used to classify the stage of ovarian maturation. The GSI increased gradually with ovarian development. Oocytes in the perinucleolus, cortical alveolus, and oil droplet stages were present in ovaries throughout the year. Early and late yolk globule stages appeared during August–September indicating that yolk formation begins during late summer. The migratory nucleolus through maturation stages were detected during November–January. Post ovulatory follicles were present during November–March, and GSI values rapidly decreased in February. Results indicate that spawning occurs during November–February and peaks during December–January.     

注射含雄烯二酮的微囊诱导日本鳗鲡性腺发育成熟的研究

研制了含雄烯二酮(4-androstene-3,17-dione,ADSD)的邻苯二甲酸醋酸纤维素微囊(4-androstene-3,17-dione-cellulose acetate phthalate-microcapsule,ACM),并对对日本鳗鲡进行注射催熟实验,间隔25 d注射ACM 3次可诱导75%的雄鳗达到性成熟.间隔25 d注射ACM 4次可诱导雌鳗平均GSI达到33.54%.注射ACM微囊制剂后,可明显促进鳗鲡血清及脑垂体GtH含量的升高.其中雄鳗注射微囊制剂1次后,血清GtH含量即显著高于对照组;雌鳗在第2次注射微囊制剂后,血清GtH含量开始显著升高.     

大连塔河湾海区虾夷扇贝的性腺发育与繁殖规律

用组织学方法对大连塔河湾海区养殖虾夷扇贝Patinopecten yessoensis的性腺发育和繁殖规律进行了研究。结果表明:根据生殖细胞的发育过程,虾夷扇贝的性腺发育可分为5个时期,即增殖期、生长期、成熟期、排放期和休止期;塔河湾海区浮筏养殖的虾夷扇贝性腺指数峰值出现在3月中旬,为17.27;该扇贝的繁殖期为4～5月,繁殖盛期为4月中下旬,繁殖期水温为5.0～6.8℃。     

色林错裸鲤性腺发育的组织学研究

采用组织切片法,对西藏特有鱼类林错裸鲤的性腺发育、产卵时间和产卵类型等进行了研究。其性腺的发育可分为六个时期,卵母细胞的发育分为5个时相。在第2时相晚期到第3时相早期,卵母细胞中具有卵黄核和核仁物质外排现象,核仁排出的可能与核周的颗粒卵黄形成有关。第2时相到第4时相早期,核膜外侧具有一透明层。产卵后未提出的成熟卵粒通过颗粒细胞吸收和利用,已达性成熟年龄的个体并不是每年都参与繁殖活动,具有繁殖间隔现象。产卵时间始于4月上旬,持续到8月上旬。色林错裸鲤属于分次同步产卵类型。