936 resultados para gonad maturation


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The present study was conducted to assess the potential toxicity of the effluent from a large sewage treatment plant (GBD-STP) in Beijing. Japanese medakas (Oryzias latipes) at reproduction active period were exposed to a serial of graded concentrations of the effluent or 100 ng l(-1) of 17-alpha-ethinylestradiol (EE2, positive control). Growth, gonadosomatic index (GSI), hepatosomatic index (HSI), reproductive success, induction potency of vitellogenin (VTG) in male fish and that of 7-ethoxyresorufin-o-deethylase activity (EROD) in male fish liver were used as test endpoints. The growth suppression of fish was observed in a dose-dependent manner, resulting in significant differences in both body length and body weight of medaka above 5% effluent. This effluent can inhibit the growth of gonad of medakas and are more sensitive to male than to female. At exposure concentration of 40% and higher, there was an unexpected decrease of HSI values, which may be resulted from sub-lethal toxicity of effluent to fish liver. VTG of plasma in males were induced in all exposure concentration levels, but not in a dose-dependent manner. The concentration of 5% effluent would be the lowest observed adverse effect level (LOAEL) affecting reproductive success when examining fertile individuals, fecundity and fertilization rate. The overt CYP1A response and higher reproductive toxicity may be indicative of low process efficiency of this STP. (c) 2004 Elsevier Ltd. All rights reserved.

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Tissue distributions and seasonal dynamics of the hepatotoxic microcystins-LR and -RR in a freshwater snail (Bellamya aeruginosa) were studied monthly in a large shallow, eutrophic lake of the subtropical China during June-November, 2003. Microcystins (MCs) were quantitatively determined by High-Performance Liquid Chromatography (HPLC) with a qualitative analysis by a Finnigan LC-MS system. On the average of the study period, hepatopancreas was the highest in MC contents (mean 4.14 and range 1.06-7.42 mug g(-1) DW), followed by digestive tracts (mean 1.69 and range 0.8-4.54 mug g(-1) DW) and gonad (mean 0.715 and range 0-2.62 mug g(-1) DW), whereas foot was the least (mean 0.01 and range 0-0.06 mug g(-1) DW). There was a positive correlation in MC contents between digestive tracts and hepatopancreas. A constantly higher MC content in hepatopancreas than in digestive tracts indicates a substantial bioaccumulation of MCs in the hepatopancreas of the snail. The average ratio of MC-LR/MC-RR showed a steady increase from digestive tracts (0.44) to hepatopancreas (0.63) and to gonad (0.96), suggesting that MC-LR was more resistant to degradation in the snail. Since most MCs were present in the hepatopancreas, digestive tracts and gonad with only a very small amount in the edible foot, the risk to human health may not be significant if these toxic parts are removed prior to snail consumption. However, the possible transference of toxins along food chains should not be a negligible concern. (C) 2004 Elsevier Ltd. All rights reserved.

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Vitellogenin (Vtg) is the precursor of yolk protein. Its expression and secretion are estrogen-regulated and are crucial for oocyte maturation. An in vitro xenoestrogen screening model was established by measuring Vtg induction in cultured primary hepatocytes from crucian carp. Vtg production was detected by biotin-avidin sandwich ELISA method while Vtg and cytochrome P4501A1 (CYP1A1) mRNA induction were measured by semi- quantitative PCR-primer dropping technique. Vtg and Vtg mRNA were dose-dependently induced by diethylstilbestrol (DES, 0.2-200 ng/mL) in hepatocytes of crucian carp. Co-treatment of the DES-induced hepatocytes with either 2,3,7,8-TCDD (TCDD, 0.1-4 pg/mL) or benzo[a]pyrene (B[a]P, 5-1000 ng/mL) resulted in a reduction of Vtg production and an increment of CYP1A1 mRNA expression both in a dose dependent manner, indicating the anti-estrogenic effects of the compounds. However, at lower tested concentrations, TCDD (0.1, 0.2 pg/mL), B[a]P (5 ng/mL) seemed to have a potentiating effect on Vtg expression and secretion, although by their own these compounds had no observable estrogenic effect on Vtg induction. Tamoxifen (a selective estrogen receptor modulators, 1 nmol/L-1 mumol/L), and P-naphtho-flavone (beta-NF, an aryl hydrocarbon receptor inducing compounds, 2.5-1000 ng/mL) also were employed to study the possible interactions in DES-induced Vtg expression. In co-treatment of the DES-induced hepatocytes with beta-NF or tamoxifen, the decrease in Vtg production did parallel induction of CYP1A1 for beta-NF, but tamoxifen inhibited Vtg induction did not parallel induced CYP1A1 expression in all test concentrations. On the contrary, it was found that in co-treatment of the TCDD-induced hepatocytes with DES, TCDD induced CYP1A1 mRNA production was inhibited by DES also. These results implicated a possible cross talk between estrogen receptor- and aryl hydrocarbon receptor-mediated pathways in the hepatocytes.

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Differential gene expression of mature and immature Bothriocephalus acheilognathi cestodes was analyzed using the suppression subtractive hybridization technique. Five mature-associated cDNAs were isolated and characterized. Virtual Northern blot and RT-PCR analyses confirmed that four of the five genes were up-regulated in mature parasites. The sequence analysis revealed that one gene encoded the structural protein chorion precursor, and that three encoded functional proteins homologous to yolk ferritin, sodium/hydrogen exchanger and muscin-like protein. Another gene appeared to be specific to B. acheilognathi, encoding a putative metal-bound protein. Although results obtained in the present study are preliminary, the information about the five genes may provide clues for further investigation on the decline in parasite numbers during the maturation of B. acheilognathi.

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Potential roles of Clq/tumor necrosis factor (TNF) superfamily proteins have been observed in vertebrate oogenesis and oocyte maturation, but no ovary-specific member has been identified so far. In this study, we have cloned and identified a novel member of Clq family with a Clq domain in the C-terminal from fully grown oocyte cDNA library of color crucian carp and demonstrated that the gene might be specifically expressed in ovary and therefore designated as Carassius auratus ovary-specific Clq-like factor, CaOClq-like factor. It encodes a 213 amino acid protein with a 17 amino acid signal peptide. There is only one protein band of about 24.5 kDa in the extracts from phase I to phase IV oocytes, but two positive protein bands are detected in the extracts of mature eggs and fertilized eggs. Furthermore, the mobility shift of the smaller target protein band cannot be eliminated by phosphatase treatment, but the larger protein band increases its mobility on the gel after phosphatase treatment, suggesting that the larger protein might be a phosphorylated form. Immunofluorescence localization indicates that the CaOClq-like proteins localize in cytoplasm, cytoplasm membrane and egg envelope of the oocytes at cortical granule stage and vitellogenesis stage, whereas they were compressed to cytoplasm margin in ovulated mature eggs and discharged into perivitelline space between cytoplasm membrane and egg envelope after egg fertilization. Further studies on distribution and translocation mechanism of the CaOClq-like factor will be benefit to elucidate the unique function in oogenesis, oocyte maturation and egg fertilization. (C) 2004 Elsevier Inc. All rights reserved.

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We have cloned and characterized the full-length cDNA encoding thyroid-stimulating hormone beta-subunit (TSHbeta) from orange-spotted grouper Epinephelus coioides. It contains 913 nucleotides with an open reading frame encoding 146 amino acids with a 20 amino acid signal peptide. The grouper mature TSHbeta has 75, 70, 61, 59, 41, 42 and 40% identities to that of rainbow trout, Atlantic salmon, zebrafish, European eel, chicken. mouse and human, respectively. RT-PCR analysis indicated that the TSHbeta mRNA was expressed abundantly not only in pituitary but also in gonads. A more interesting finding is to reveal the differential TSHbeta expressions between the ovaries and the transitional gonads or testes in natural individuals of orange-spotted grouper and red-spotted grouper Epinephelus akaara, and in artificial sex reversal individuals of red-spotted grouper induced by MT feeding. In situ hybridization localization provided direct evidence that the TSHbeta was transcribed in the germ cells. In the growing oocytes, the TSHbeta transcripts were concentrated on the ooplasm periphery. In testicular tissues, the intensively expressed TSHbeta cells were found to be spermatogonia and spermatocytes in the spermatogenic cysts. This is the first report of a TSHbeta expressed in the gonads of any vertebrates in addition to the expected expression in the pituitary, and it expresses more transcripts in the gonads during sex reversal or testis than in the ovaries both in E. coioides and E. akaara. Importantly, the TSHbeta identification in germ cells allows us to further investigate the functional roles and the molecular mechanisms in gametogenesis of groupers, especially in sex reversal and in spermatogenesis. (C) 2004 Elsevier Ireland Ltd. All rights reserved.

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Gynogenetic silver crucian carp, Carassius auratus gibelio, is an intriguing model. system. In the present work, a systemic study has been initiated by introducing suppression subtractive hybridization technique into this model system to identify the differentially expressed genes in oocytes between gynogenetic silver crucian carp and its closely related gonochoristic color crucian carp. Five differential cDNA fragments were identified from the preliminary screening, and two of them are ZP3 homologues. Moreover, the full length ZP3 cDNAs were cloned from their oocyte cDNA libraries. The length of ZP3 cDNAs were 1378 bp for gyno-carp and 1367 bp for gono-carp, and they can be translated into proteins with 435 amino acids. Obvious differences are not only in the composition of amino acids, but also in the number of potential O-linked oligosaccharide sites. In addition, gyno-carp ZP3 amino acid sequence has an unexpected higher identity value with common carp (83.5%) than that with the closely related gono-carp (74.7%). The unique homology may be originated from the ancient hybridization. Northern blot analysis confirmed that expression of the ZP3 gene occurred exclusively in the oocytes. Because O-linked oligosaccharides on ZP3 have been demonstrated to play very important roles in fertilization, it is suggested that the extra O-linked glycosylation sites may be related to the unique sperm-egg recognition mechanism in gynogenesis.

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The sexual ratio of Gobiocypris rarus exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) and 17 beta -estradiol from embryo to sexually mature revealed feminization and overdevelopment of connective tissue in male fish gonad in 2-30 pg/L TCDD concentration range. Daphnia magna was not sensitive to the high dose of TCDD (0.1-1000 ng/ml), but the reproduction of D. magna treated with TCDD decreased after the 8th day. 7-Ethoxyresorufin-O-deethylase (EROD) activities in newly fertilized eggs of G. rarus exposed to TCDD dosage groups (1000-100,000 pg/L) were significantly induced and increased with TCDD concentrations at the early life stage, while no difference was found between low TCDD dosage groups (<100 pg/L), but a good relationship between the EROD activity and the TCDD concentration was observed during a long-term developmental stage. There was a pericardial edema formed in a 2-week yolk-sac at the concentration of 1000 pg/L TCDD. But in the exposure group (2 pg/L TCDD for 120 days), the cell nuclei of hepatocytes was far from the center and packed toward the cell membrane; the cristae of most mitochondria in the cell dropped and collapsed; the rough endoplasmic reticulum broke into fragments; and numerous lipid droplets formed in the cell. (C) 2001 Academic Press.

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A pathogenic virus (RGV), isolated from diseased pig frog Rana grylio with lethal syndrome, was investigated with regard to morphogenesis and cellular interactions in EPC cells, a cell Line from fish. Different stages of virus amplification, maturation and assembly were observed at nucleus, cytoplasm and cellular membranes. The matured virus particles, were not only distributed diffusely in nucleus, cytoplasm and cellular surface, but also aggregated as pseudocrystalline arrays in the cytoplasm. Virions were released by budding from the plasma membranes, or following cell lysis. Various types of cell damage, such as small vacuoles, spherical inclusions, and swollen and empty mitochondria, were also found. Some typical characteristics of RGV, such as the symmetrical shape of the virions, replication process involving both nuclear and cytoplasmic phases, budding release from cellular membrane and intracellular membrane, viromatrix and paracrystalline aggregation in cytoplasm, and its acute pathogenic effects, were observed to be similar to that of other iridoviruses. Therefore, the RGV appears to be a member of the Iridoviridae based on these studies. (C) 1999 Elsevier Science B.V. All rights reserved.

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The effects of estradiol (E(2)) on growth hormone (GH) production was investigated in gonad-intact female goldfish. It was first necessary to generate a specific antibody for use in immunocytochemistry, Western, and dot-blot analyses of GH production. To accomplish this, grass carp GH (gcGH) cDNA was cloned by the reverse transcription polymerase chain reaction (RT-PCR) and expressed in Echerichia coli and a specific polyclonal antibody to recombinant gcGH was generated in the rabbit. In Western blot, the anti-gcGH antibody specifically immunoreacted with recombinant gcGH, purified natural common carp GH, and with a single 21.5-kDa GH form from pituitary extracts of grass carp, common carp, goldfish, and zebrafish but not salmon, trout, or tilapia. Intraperitoneal injection of the recombinant gcGH enhanced the growth rates of juvenile common carp demonstrating biological activity of this GH preparation. Electron microscopic studies showed that the anti-gcGH-I antibody specifically reacted with GH localized in the secretory granules of the goldfish somatotroph. Using anti-gcGH-I in a dot-blot assay, it was found that in vivo implantation of solid silastic pellets containing E(2) (100 mu g/g body weight for 5 days) increased pituitary GH content by 150% in female goldfish. In a second, independent study employing a previously characterized anticommon carp GH antibody for radioimmunoassay, it was found that E(2) increased pituitary GH content by 170% and serum GH levels by approximately 350%. The E(2)-induced hypersecretion of GH and increase in pituitary GH levels was not associated with changes in steady-state pituitary GH mRNA levels, suggesting that this sex steroid may enhance GH synthesis at the posttranscriptional or translational level. Previous observations indicate that GH can stimulate ovarian E(2) production. The present results show that E(2) can in turn stimulate GH production, indicating the existence of a novel pituitary GH-ovarian feedback system in goldfish. (C) 1997 Academic Press.

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As one of the most powerful tools in biomedical research, DNA sequencing not only has been improving its productivity in an exponential growth rate but also been evolving into a new layout of technological territories toward engineering and physical disciplines over the past three decades. In this technical review, we look into technical characteristics of the next-gen sequencers and provide prospective insights into their future development and applications. We envisage that some of the emerging platforms are capable of supporting the $1000 genome and $100 genome goals if given a few years for technical maturation. We also suggest that scientists from China should play an active role in this campaign that will have profound impact on both scientific research and societal healthcare systems.

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树突状细胞(dendritic cells, DC)作为机体天然免疫和获得性免疫反应的桥梁和枢纽,发挥着重要的启动和调控作用。随着体外诱导方法的建立和生物学技术的进步,有关DC 的基础生物学研究得到了快速的发展,在诱导方法、个体发生及基因表达和调控等方面,涌现出很多新的、未解的关键问题。同时,随着对粘膜免疫机理研究的深入,DC 在粘膜生态环境中的功能和影响,渐已成为免疫学研究前沿领域中的热点和要点。在本研究中,为了确定DC 体外分化成熟的最短时程,同时为了研究DC 分化成熟相关的基因表达调控,我们建立了快速的DC 体外诱导方法,分析了体外快速诱导 DC 的mi/mRNA 表达谱。此外,在原始分离的女性生殖道共生乳酸杆菌的基础上,以THP-1作为DC 前体细胞的细胞系模型,开展了女性生殖道共生乳酸杆菌刺激活化 THP-1 的研究,希望能够为乳酸杆菌作为生殖道粘膜免疫疫苗的应用提供理论基础。首先,采用外周血单个核细胞(peripheral blood mononuclear cells, PBMC)来源的CD14+细胞为DC 前体,经过GM-CSF 和IL-4 的刺激,1-6 天后得到未成熟DC (immature dendritic cells, iDC),并经成熟因子(TNF-α, IL-1β, IL-6 与PGE2)诱导 1-2 天后,获得成熟DC(mature dendritic cells, mDC)。经过比较和分析,明确了完全分化和成熟各2 天,即“2+2”,为DC 诱导分化的最佳和最短时程,从而证实和建立了DC 体外快速诱导的体系和方法。该方法获得的iDC 与mDC,具有与传统的“6+2” 方法获得的DC 相同的形态与表型,而且,利用该方法获得的DC 总数高于“1+1”, “1+2”与“6+2”的方法,为DC 的生物学研究提供了基础数据。我们进而采用芯片技术,对体外快速分化成熟的DC 进行了mi/mRNA 表达谱分析,确定了DC 不同分化发育阶段特征性的mi/mRNA 表达差异。结果发现,与CD14+ 单核细胞即DC 前体相比,iDC 与mDC 之间具有更加相近的mi/mRNA 表达方式。 miRNA 表达谱分析则表明,不同的miRNA 表达与DC 的不同分化和发育阶段相关。而且,位于同一基因簇内的miRNA,呈现协同表达的情况。特别值得注意的是,本研究发现了在DC 的某些发育阶段特异表达的miRNA,它们在DC 发育过程中的功能,还未得到诠释,它们在DC 某些分化阶段的特异表达,提示了DC 各分化阶段的相关性与特异性。结合mRNA 表达谱分析,我们发现miRNA 的表达与其目的基因的表达在mRNA 水平呈现负相关的特性。同时,免疫相关mRNA 与miRNA 在DC 体外不同发育阶段的表达亦呈现差异,其中,miRNA(如hsa-miR-181a, hsa-miR-223, hsa-miR-155, hsa-miR-146, hsa-miR-106a 与hsa-miR-20a 等)与mRNA(如ALM1 等)参与了特定的与免疫相关的GO(Gene Ontology)与通路(Pathway),提示这些miRNA 与mRNA 可能通过不同的方式调节控制着DC 的体外诱导过程。在有关粘膜生态环境中DC 的分化、成熟及其功能影响的研究中,我们首先通过各种乳酸杆菌鉴定方法的综合应用,确定了6 种原始分离的女性生殖道主要共生乳酸杆菌:发酵乳酸杆菌(L.Fermentum)、约氏乳酸杆菌(L.Johnsonni)、卷曲乳酸杆菌(L.Crispatus)、革氏乳酸杆菌(L.Gasseri)、詹氏乳酸杆菌(L.Jensenii)与德氏乳酸杆菌(L.Delbrueckii )。其中,德氏乳酸杆菌(L.Delbrueckii)和发酵乳酸杆菌(L.Fermentum)具有较高的产H2O2 的能力。在此基础上,我们在与THP-1 的共同培养体系中,将乳酸杆菌对DC 前体的作用和影响进行了比较和研究。结果发现,L.Crispatus 在分离的各原始菌株中,具有最强的刺激THP-1 活化的能力,而且,在相同刺激比例下,L.Crispatus 活菌具有比死菌更强的免疫刺激能力,表现为明显上调THP-1 细胞表面标志CD40、CD80、CD86、 CD1a、CCR6 与CD324 的表达水平,同时可诱导活化THP-1 上调表达Th1 型细胞因子。通过FITC-Dextran 吞噬实验,我们发现,经过L.Crispatus 刺激的THP-1 细胞,其吞噬外来抗原的能力明显下降,但尚未检测到经过活化的THP-1 细胞刺激T 细胞增殖的能力。通过流式细胞术分析的方法,我们检测了TLR1、TLR2、TLR4 与TLR6 在不同的刺激分化阶段的表达水平,结果表明,THP-1 主要通过TLR2 与TLR6 识别女性生殖道L.Crispatus。综上所述,本研究首先通过对DC 体外分化成熟的最短时程的分析,确立了快速诱导DC 的最佳方法,进而利用芯片技术,研究了快速诱导DC 的mi/mRNA 表达谱,揭示了DC 体外分化发育过程中可能的调控途径,为进一步研究DC 的基础生物学提供了恰当的模型和具有指向性的线索。同时,通过与DC 前体THP-1 的共同培养体系,证实了生殖道共生乳酸杆菌的免疫调节作用,为以乳酸杆菌为载体的生殖道粘膜免疫疫苗的研究和应用提供了实验依据

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尽管体细胞核移植(somatic cell nuclear transfer, SCNT)技术仍然处于 起步发展阶段,但是随着体细胞核移植技术在近些年来的飞速发展,人们已经得 到了多种哺乳动物体细胞核移植的存活后代。体细胞核移植技术在生物医药、农 业及其它领域的应用显示了这项技术的巨大发展前景。另一方面,人们发现体细 胞核移植效率低下并且体细胞克隆动物存在许多缺陷,这些主要是由于核移植技 术,供体细胞选择,体外培养系统以及卵母细胞的状态等的差异导致的。本研究 主要围绕着这些因素在体细胞核移植过程中对于克隆胚胎植入前后发育的影响 而开展,目的在于提高体细胞核移植的效率。 实验一,研究了几个因素对克隆胚胎发育和克隆效率的影响,为提高体细胞 核移植效率提供一些依据。这部分研究主要包括四倍体半克隆小鼠研究和蛋白酶 体抑制剂在克隆胚胎和孤雌激活胚胎发育中的影响。四倍体体细胞半克隆 (tetraploid semi-cloned , TSC)胚胎的体外发育结果表明,虽然TSC 胚胎可 能避免二倍体半克隆胚胎发育过程中的非整倍体现象,但是仍然不能形成胎儿。 另外,利用蛋白酶体抑制剂MG132 处理克隆胚胎的结果表明,虽然MG132 通过抑 制成熟促进因子(maturation promoting factors,MPF)活性的降低可以提高 克隆胚胎的体外发育率,但是没有改变克隆胚胎的质量。 实验二,研究了克隆技术在克隆胚胎构建和发育上的影响。首先,我们研究 了完整颗粒细胞注射到卵母细胞中所引起的变化。我们发现完整的颗粒细胞注入 到卵母细胞中之后很快引起细胞膜裂解和细胞核碎裂,从而导致激活后重构胚胎 的碎裂。这一实验表明完整供体细胞核注入的方法不适用于小鼠体细胞克隆。接 下来我们研究了不同的核移植技术――利用piezo 的直接注射法(piezoelectric microinjection,PEM)和电融合法(Electrofusion,EF)――对植入前后的克隆胚 胎以及出生后的克隆动物的影响。研究的结果发现,在PEM 法中,提高piezo 脉 冲的强度会导致供体细胞核DNA 断裂增加,使植入前克隆胚胎的细胞数目减少, 凋亡增加,从而降低克隆胚胎的质量。相反,在用EF 法产生的胚胎中细胞核DNA 的断裂很少,克隆胚胎质量相对较好。实验的结果表明,由于两种克隆技术利用 的原理不同,会对克隆胚胎的发育产生一定的影响,从而改变克隆的效率。 实验三,研究了猕猴体细胞克隆胚胎早期发育过程中细胞核内有丝分裂器蛋 白[Nuclear Mitotic Apparatus Protein,NuMA]的表达和分布。尽管在有些猕猴体 细胞核移植胚胎中没有检测到NuMA 的正确表达和分布并且有些胚胎出现了微 管组装异常,但是大多数猕猴体细胞核移植胚胎具有正常的NuMA 蛋白表达和 正常的核型。通过改进操作技术我们得到了可以发育到正常囊胚的猕猴体细胞核 移植胚胎。这些结果提示猕猴SCNT 胚胎发育失败的原因不是NuMA 等重要蛋 白的缺失。

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通过趾骨切片可以准确鉴定年龄,了解一个物种的最长寿命,也为我们研究确定一个物种的生长特点、性成熟期,以及一个地区一个物种的年龄结构、种群生态(Marnell,1998)和群落生态提供重要信息(Morrison,et a1.,2004)。 本论文使用骨骼鉴龄法对中国浙江省宁波市北仑瑞岩寺林场的镇海棘螈(Echinotriton chinhaiensis)雌性繁群进行了年龄结构研究。结果显示:第一次参加繁殖的年龄为3龄;繁群中数量占优势的是5龄、6龄。而在6龄以后参加繁殖的雌性个体数便开始随着年龄的增大而逐渐减少。参加繁殖的雌性年龄最大个体为8龄。平均年龄为5.13龄。同时对其年龄和头体长、体全长的相关性检验,发现其年龄与头体长和体全长不相关,镇海棘螈雌性的生长方式表现为性成熟后能量主要用于繁殖。 另外,对李子坪大凉疣螈(Tylototriton taliangensis) 雄性繁群进行了年龄结构研究。结果显示:大凉疣螈雄性第一次参加繁殖的年龄为4龄;繁群中数量占优势的是5龄、6龄、7龄。而在7龄以后参加繁殖的雄性个体数便开始随着年龄的增大而逐渐减少。参加繁殖的雄性中年龄最大的个体为10龄。平均年龄为6.7龄。对其年龄和头体长、体全长的相关性检验,发现其年龄与头体长和体全长不相关,大凉疣螈雄性生长特点也表现为性成熟后生长缓慢的特点。 研究材料方面,本文采用野外采样与标本馆标本相结合的方式获得了中国蝾螈科2个重要保护物种繁殖群体的剪(指)趾材料,使得建立于其上的年龄结构工作更加可靠、更加具有代表性。 此外,本论文讨论了镇海棘螈瑞岩寺种群繁殖总量年度间的差异及其产生原因。将1998、1999、2000、2008、2009年镇海棘螈(Echinotriton chinhaiensis) 瑞岩寺种群的繁殖量进行比较,发现虽然雌性平均窝卵数比较稳定,但繁殖总量小于1998、1999、2000年任何一年总产卵量的50%。对2008年镇海棘螈繁殖量大幅下降的原因分析发现, 2007年9、10月影响严重台风的两次强台风、瑞岩寺景区开发等因素可能是造成近年该种群繁殖量大幅下降的原因。而2008年初50年不遇的低温是否影响镇海棘螈的繁殖值得进一步追踪研究。2009年繁殖量较2008年没有明显的增长,可能是由于2007年的台风影响了其繁殖营养的积累。台风的影响可能存在滞后现象,对此有待进一步监测证明。 本研究首次对中国蝾螈科物种进行的年龄结构鉴定,为进一步了解中国蝾螈科动物的种群生态打下了坚实的基础。 Using skeletochronology, we can know the life span of a species, age of reaching sexual mature, and of course age structure, which are vital(Morrison,et a1.,2004). Skeletochronology was performed on Echinotriton chinhaiensis Ruiyansi female population. The result shows that: The oldest individuals were 8 years old and the youngest ones were 3 years old. Individuals of age class 5(39.13%) and 6(21.74%) were most numerous. The number of individuals participated in reproduction decreased with the increase of age after the sixth year. Average age is 5.13 years. There is no correlation between age and body size (SVL and TL). For female chinhai salamander, energy is devoted to reproduction after reaching sexual maturation. While using skeletochronology to study Tylototriton taliangensis Liziping male population, the oldest individuals is 10 years old, and the youngest ones is 4 years old. Individuals of the age class 5, 6, and 7 dominat this population. The number of individuals decrease with the increase of age also after the seventh year. Average age is 6.7 years old in this population. there is also no correlation between age and body size (SVL and TL).It turned out that T. taliangensis tend to grow slowly after reaching sexual maturation. In this thesis, specimens from both wild and museum were used to gain enough toe clipping samples. A big sample size guarantees the reliability of this study. In the meantime, E. chinhaiensis’s annual reproduction of the year 1998, 1999, 2000 ,2008,and 2009 was compared. The result shows there is a huge decline in E. chinhaiensis’s annual reproduction in 2008,even the egg clutch is very stable. After analyzing, it turned out the huge decline in 2008 was probably caused by typhoon in 2007, besides the effect of tourism development and cash crop planting. While the impact of extreme weather of 2008 on reproduction needs further investigation. In the year 2009, there is no obvious increase in annual reproduction. It maybe due to lasting impact of typhoon in 2007. It is the first age-structure study on these two Chinese salamanders. A solid foundation was laid for further population ecology study of these two species.