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1.
半滑舌鳎性腺分化的组织学观察   总被引:16,自引:3,他引:16  
运用组织学方法,对半滑舌鳎性腺的发育和分化过程进行了观察。半滑舌鳎的性腺发育为雌雄异体的分化类型,可以分为3个阶段:性腺的原始阶段、性腺分化前期阶段和性腺分化完成阶段。在50日龄以前,原始性腺形成但未分化。62日龄,个体达到40.5mm时,一种性腺形成了成簇发育的原始细胞群,性腺迅速增大变宽,后来发育成为卵巢;另一种仍处于休止阶段,相对较小,后来发育为精巢。雌鱼在120日龄形成明显的卵巢腔,开始了细胞学的分化;精巢在100日龄精原细胞开始快速增殖,体细胞有丝分裂,形成输精管原基,在150日龄左右开始细胞学的分化,并形成精小叶,190日龄左右出现初级精母细胞,性腺分化基本完成。雌鱼性腺分化时期早于雄鱼。  相似文献   

2.
大黄鱼性腺性别分化的组织学观察   总被引:4,自引:2,他引:2  
利用组织学方法研究了大黄鱼的性腺分化和发育规律。大黄鱼受精卵于2009年9月22日开始孵化,孵化水温26℃,育苗水温22.0~25.8℃,养殖水温11.5~25.6℃。20日龄稚鱼(体长17.6~19.2 mm)腹腔中一对原始性腺已经形成。55日龄幼鱼(体长27.5~37.0 mm)半数个体性腺中形成成簇发育的卵原细胞群,标志着卵巢解剖学分化开始。减数分裂和卵巢腔的形成同时开始于60日龄(体长28.0~37.2 mm)。120日龄幼鱼(体长39.2~51.0 mm)性腺中,初级卵母细胞出现,标志着卵巢细胞学分化的开始。精巢分化开始于第95日龄(体长38.0~48.0 mm),其解剖学标志为生精导管的形成及体细胞在性腺中的散布方式。145~195日龄,由于水温过低,鱼苗停止生长,期间性腺发育水平没有明显变化。215日龄幼鱼(体长44.0~59.2 mm)性腺中精母细胞的出现标志着精巢细胞学分化的开始。精小叶于230日龄(体长56.2~72.8 mm)形成。由此可见,大黄鱼雌性性腺发育早于雄性性腺,且大黄鱼性腺分化类型属于分化型雌雄异体型。  相似文献   

3.
多鳞铲颌鱼性腺分化发育的组织学研究   总被引:1,自引:0,他引:1       下载免费PDF全文
用光镜和透射电镜对多鳞铲颌鱼(Varicorhinus macrolepis)性腺的分化发育进行组织学研究,观察了雌雄性腺的形成过程及各级生殖细胞的形态特征。结果表明,多鳞铲颌鱼卵巢和精巢开始分化的时间分别在80日龄和90日龄,雌鱼和雄鱼的性成熟年龄分别为36月龄和24月龄,精子和卵子的发育均可分为5个时期。在多鳞铲颌鱼的生长发育过程中,12月龄(雄鱼)和30月龄(雌鱼)性腺质量与体长、体质量之间具有极显著的相关关系。  相似文献   

4.
本研究通过人工配对方式对福氏刺尻鱼的性逆转进行了诱导,并从形态学和组织学层面对其性逆转过程和性腺发育进行了研究。结果表明,福氏刺尻鱼的性腺分为纯雌鱼卵巢、纯雄鱼精巢和雌雄(♀/♂)兼性期性腺3种类型。性腺均先分化为卵巢;性逆转发生于第II期卵巢阶段,通过1大1小配对诱导1~2周时,大个体雌鱼第II期卵巢停止发育并逐渐萎缩,在卵巢壁和产卵板上逐渐分化出雄性生殖细胞,性腺内雌雄生殖细胞共存,形成兼性期性腺,即为雌雄同体阶段;配对诱导3周后,兼性期性腺完全分化为早期精巢,完成性逆转,个体成为功能性雄鱼;配对诱导4周后,性逆转的雄鱼精巢和小个体雌鱼的卵巢发育成熟,开始排精产卵。本文还分析了福氏刺尻体长、体重与性逆转的关系,并对性逆转过程、特点及可能的诱导机制进行了探讨。研究结果可为开展福氏刺尻鱼人工繁育和性别控制技术研究提供理论指导,也为揭示其性腺发育及性逆转机制奠定了基础。  相似文献   

5.
为探明厚唇裂腹鱼的精巢、卵巢周年发育及血清中性激素含量的变化,2020年8月—2021年8月,每月在克孜勒河采样,获得样本共计194尾,采用常规石蜡切片方法对其精巢和卵巢进行观察,以耳石为鉴定材料对厚唇裂腹鱼最小性成熟个体年龄进行研究,选取成熟鱼卵描绘卵径分布判断其产卵类型,采用酶联免疫法测定厚唇裂腹鱼各发育周期的雌二醇和睾酮的质量浓度。试验结果显示:厚唇裂腹鱼精巢和卵巢发育分为6个时期;雄鱼最小性成熟个体年龄为2龄,雌性最小性成熟个体年龄为3龄,精巢发育早于卵巢;厚唇裂腹鱼产卵期在3—5月,卵粒的数量百分比在直径2.9~<3.1 mm时出现峰值,产卵后的Ⅵ期卵巢中极少存在成熟的卵粒,判断其产卵类型为完全同步产卵类型;雌鱼与雄鱼血清中雌二醇和睾酮的质量浓度均在Ⅴ期时达到最高。厚唇裂腹鱼属于完全同步产卵类型,性腺于2017年3—5月发育成熟并产卵,雌二醇和睾酮的质量浓度在厚唇裂腹鱼繁殖期间显著增加。  相似文献   

6.
尼罗罗非鱼性腺发育的研究   总被引:2,自引:1,他引:2  
<正> 本文主要研究尼罗罗非鱼从刚孵出的仔鱼直至第一次性成熟的亲鱼,用组织学方法观察其性腺分化和发育的全过程。长江流域各地区尼罗罗非鱼性成熟日龄为130天左右。在合理的饲养条件下个体生长速度和性腺发育是随日龄的增长同时并进的,雌雄个体生长速度和性腺发育基本上同步,然而在达到性成熟产卵以后,雄鱼生长速度显著的超过雌鱼。  相似文献   

7.
每天采样观察3~60日龄人工养殖的黄颡鱼Pelteobagrus fulvidraco性腺分化和发育的组织学。结果表明:在水温(20±4)℃下,黄颡鱼卵巢的分化明显早于精巢,性腺的分化型为雌性异体型。孵出后14d卵巢开始分化,原始性腺在横切面出现组织突起,逐步形成卵巢腔;雄性分化始于孵出后54d,主要标志是形成输精管原基,进而形成输精管。本研究成果为黄颡鱼的人工繁殖提供了理论依据。  相似文献   

8.
为掌握养殖银鲳的性腺发育规律及其与性类固醇激素水平的关系,本研究采用组织切片技术和酶联免疫吸附法(Elisa),观察养殖条件下银鲳的精巢与卵巢发育特征和血清中性类固醇激素的周年变化,并分析性腺成熟指数(GSI)、肝重指数(HSI)和肥满度(CF)与性腺发育的关系。结果显示,养殖银鲳雌鱼1龄即可发育成熟,成熟卵巢呈一对""形的囊状结构。11月份有近一半个体发育至III期,33.3%已发育至IV期,12月—翌年1月越冬期间约2/3退化至II期,3月又迅速发育至IV期,4月份达到V期并产卵,5月份产卵结束卵巢进入恢复期IV期。银鲳精巢属小叶型,III期精巢出现小叶腔,IV期精巢出现精子,精巢发育速率快于卵巢,即"雄性早熟",7月龄约20%个体可达到性成熟,越冬时退化至III期,3月重新发育,精子分批成熟排精。雌鱼GSI值为0.19%~12.89%,HSI为0.97%~2.30%,CF为2.30~3.08 g/cm~3,雄鱼的GSI为0.08%~2.62%,HSI值为0.73%~1.83%,CF为2.11~2.80 g/cm~3,GSI值在V期时达到最大,HSI和CF值则于IV期达到峰值。雌鱼血清中雌二醇(E2)周年表达水平为23.27~59.13 pg/m L,雄鱼为15.90~36.20 pg/m L,雌鱼的睾酮(T)为14.57~68.67 nmol/L,雄鱼的T为18.62~66.49 nmol/L,E2水平与HSI值呈现显著正相关关系,T表达水平与GSI值呈现显著正相关关系。研究表明,银鲳血清中性类固醇激素含量与精巢和卵巢的发育密切相关,可作为了解养殖银鲳性腺发育的重要指标。  相似文献   

9.
通过RACE方法获得半滑舌鳎(Cynoglossus semilaevis)Hh基因家族的Shh基因,该基因全长1 922 bp,其中5′UTR 266 bp,3′UTR 360 bp,ORF1 296 bp,编码431个氨基酸,经预测该多肽的相对分子质量为47.28 k D,理论等电点6.95,具有Hh基因家族特有的保守结构域。氨基酸序列分析表明,半滑舌鳎Shh与牙鲆的同源性最高,为82%,与其他鱼类同源性为74%~81%,与非洲爪蟾的同源性为61%,与人和鼠的同源性为63%~64%。甲基化结果显示,Shh基因在1龄卵巢中的甲基化程度普遍低于雄鱼与伪雄鱼精巢。基因表达分析显示,Shh基因在胚胎期的囊胚期表达显著高于其它时期(P0.05),在雌雄成鱼8个组织器官均表达,在雌性性腺分化的关键期孵化后50 d,雌性性腺中表达量较前期升高,且显著高于同时期雄性性腺中的表达(P0.05),在雄性性腺分化的关键期80~95 d,Shh基因在雄性中的表达水平显著升高(P0.05),在8月龄、1龄及2龄雌鱼性腺中表达显著高于雄鱼与伪雄鱼。本研究表明,半滑舌鳎Shh基因在进化中高度保守,与胚胎分化、组织器官形成、雌雄性腺分化及性腺发育密切相关。  相似文献   

10.
池塘养殖斑节对虾生长、发育与性成熟   总被引:1,自引:0,他引:1  
为了解不同养殖条件下斑节对虾的生长、外生殖器发育、性腺发育及性成熟之间的关系,对其养殖进行跟踪调查研究.结果显示:①斑节对虾雌雄外生殖器官发育和头胸甲长呈线性关系;②不同养殖环境条件下,斑节对虾性成熟生物学最小型个体无显著差异.雄性精荚出现的生物学最小型个体为头胸甲长3.1 cm,体长11.1 cm,体质量20.0 g;雄性性成熟个体的头胸甲长3.7 cm,体长13.0 cm,体质量37.0 g.池养雌性斑节对虾的性成熟生物学最小型个体以纳精囊的发育完全(可与雄虾交配)为标志,其最小性成熟个体的头胸甲长4.3 cm、体长15.1 cm、体质量53.0 g,雌性性成熟个体为头胸甲长5.0 cm,体长17.0 cm,体质量75.0 g以上;③池塘养殖斑节对虾性成熟与日龄和养殖环境相关.鱼塭雄虾精荚出现的最早时间为日龄120 d前后,其性成熟日龄约为160 d;池塘养殖雄虾精荚出现的最早时间为日龄150 d前后,其性成熟日龄约为260 d.鱼媪雌虾最早交配发生在日龄165 d前后,性成熟日龄205~236 d,池养雌虾最早交配发生在日龄240~ 280 d,性成熟日龄295~360 d以上.  相似文献   

11.
The timing of primordial germ‐cell (PGC) migration with regard to the gonadal anlagen, gonad formation and sex differentiation was examined histologically in the chub mackerel (Scomber japonicus) at 5–190 days post hatching (dph). At 5 dph, PGCs appeared on the peritoneal epithelium surface or in the mesentery, on the dorsal side of the abdominal cavity. By 10 dph, stromal cells around the PGCs proliferated. The gonadal primordium was formed by 15 dph. The gonadosomatic index was 0.01% at 30 dph and increased thereafter (0.32% in females and 0.04% in males at 160 dph). Ovarian differentiation occurred at 30–40 dph, indicated by ovarian cavity formation (elongation and fusion of the upper and lower ovarian edges). Meiosis was subsequently initiated. A few meiotic oocytes surrounded the cavity at 50 dph; most were in the perinucleolus stage at 60 dph and attained a diameter of 60–70 μm at 190 dph. Testicular differentiation occurred at 30 dph, indicated by the formation of the sperm duct primordium. Spermatogonia gradually proliferated, developing into spermatocytes at the chromatin–nucleolus stage (after 90 dph) and subsequently into spermatids and spermatozoa (160 dph). These data could aid the development of seeding and cell‐engineering technologies for scombrid fish.  相似文献   

12.
The aim of this study was to investigate the period of sex differentiation and the pattern of gonadal differentiation in Nibea albiflora using histological techniques. The fish were raised in temperature between 19.5 and 21.5°C. The promordial gonads formed at the posterior region of the abdomen and the fish remained undifferentiated till the 36 day post hatching (dph) with a total length (TL) of 21.20 ± 3.90 mm. Ovarian differentiation precedes testicular differentiation, as usual in teleost fish. Oocytes undergoing meiosis at zygotene (bouquet) and pachytene stages were firstly observed when the total length reached 33.05 ± 4.61 mm at 40 dph, and the formation of the ovarian cavity began simultaneously at 46 dph with total length of 49.40 ± 4.83 mm. When the mean total length reached 78.05 ± 5.24 mm (61 dph), ovarian cavity grew bigger, and oocytes were firstly detected. By contrast, signs of morphological differentiation in the presumptive testis are not observed until their total length reached 69.18 ± 5.26 mm at 55 dph. The unrestricted lobular organization of the testis is evident at the stage of TL = 78.05 ± 5.24 mm (61 dph). These findings indicate that N. albiflora is a differentiated gonochorist and the critical period of sex differentiation in N. albiflora occurs at the stage of TL = 21.20 ± 3.90 mm (36 dph).  相似文献   

13.

摘要: 采用组织学和分子生物学方法, 研究了投喂芳香化酶抑制剂来曲唑(LE)后暗纹东方鲀(Takifugu obscures)初孵仔鱼CYP19ADMRT1基因表达以及性腺的组织学变化, 以期进一步了解P450芳香化酶(P450arom)在鱼类早期性别分化过程中的作用。RT-PCR结果显示, 对照组样品CYP19ADMRT1表达显示性二态, 雌性表达CYP19A基因, 雄性表达DMRT1基因。LE处理组在性别分化期间, 雄性样品单一表达DMRT1, 雌性样品则同时表达CYP19ADMRT1qRT-PCR结果显示: LE处理组雌性仔鱼CYP19A基因表达被显著抑; 虽然在仔鱼出膜后22 d(dph)的表达水平高于9 dph, 但仅为同日对照组的2.11%LE处理组雌性样品22 dphDMRT1基因表达量上调, 150 dph时达对照组雄性水平。55 dph的性腺组织学结果表明, LE处理可导致暗纹东方鲀稚鱼原始卵巢退化, 并向功能性精巢发育。150 dphLE处理组性腺均为精巢, 并与对照组精巢发育同步。结论认为, 暗纹东方鲀性腺分化期间P450arom是卵巢形成和维持发育所必须的, 抑制P450arom活性可导致雌性暗纹东方鲀发生雄性化逆转。

  相似文献   

14.
采用组织学和分子生物学方法,研究了投喂芳香化酶抑制剂来曲唑(LE)后暗纹东方鲀(Takifugu obscures)初孵仔鱼CYP19A、DMRT1基因表达以及性腺的组织学变化,以期进一步了解P450芳香化酶(P450arom)在鱼类早期性别分化过程中的作用。RT-PCR结果显示,对照组样品CYP19A和DMRT1表达显示性二态,雌性表达CYP19A基因,雄性表达DMRT1基因。LE处理组在性别分化期间,雄性样品单一表达DMRT1,雌性样品则同时表达CYP19A和DMRT1。qRT-PCR结果显示:LE处理组雌性仔鱼CYP19A基因表达被显著抑;虽然在仔鱼出膜后22d(dph)的表达水平高于9 dph,但仅为同日对照组的2.11%。LE处理组雌性样品22 dph时DMRT1基因表达量上调,至150 dph时达对照组雄性水平。55 dph的性腺组织学结果表明,LE处理可导致暗纹东方鲀稚鱼原始卵巢退化,并向功能性精巢发育。150 dph的LE处理组性腺均为精巢,并与对照组精巢发育同步。结论认为,暗纹东方鲀性腺分化期间P450arom是卵巢形成和维持发育所必须的,抑制P450arom活性可导致雌性暗纹东方鲀发生雄性化逆转。  相似文献   

15.
石鲽仔、幼鱼性腺发育的组织学观察   总被引:1,自引:1,他引:0       下载免费PDF全文
利用组织学方法对人工培育的石鲽(Kareius bicoloratusBasiewsky)仔、幼鱼性腺发育进行研究。结果表明,性腺的发育与体长密切相关。刚孵化石鲽的原生殖细胞数目为2个,孵化3 d数目增至8个,之后经过迁移,至孵化9 d到达生殖嵴。在全长为7.2~8.5 mm(孵化9~11 d)的仔鱼中,性腺原基中的体细胞迅速增殖并包围原生殖细胞,后者在全长10~15 mm(孵化后10~35 d)的仔幼鱼中增殖成为生殖干细胞。原始性腺在全长15~30 mm(孵化40~60 d)的幼鱼中逐渐发育完善,呈细线状,位于腹腔后部中肾管下方紧贴体壁。雌性性腺最早在全长32.5 mm(孵化66 d)的个体中出现分化特征,至全长89~102 mm时雌性性腺特征完全分化。雄性性腺的分化较雌性性腺晚,最早在全长为91 mm的幼鱼中开始,至全长为114~118 mm时雄性性腺分化特征已经十分明显。  相似文献   

16.
Synaptonemal complex protein 3 (Scp3), which is encoded by scp3, is a meiotic marker commonly used to trace the timing of gonadal differentiation in vertebrates. In the present study, the ricefield eel scp3 cDNA was cloned, and a fragment encoding amino acids 49 to 244 was overexpressed. The recombinant Scp3 polypeptide was purified and used to generate a rabbit anti-Scp3 polyclonal antiserum. In adult ricefield eels, scp3 mRNA was predominantly detected in the gonads and faintly detected in discrete brain areas. In the gonads, Scp3 immunoreactivities were shown to be localized to the germ cells, including meiotic primary growth oocytes, spermatocytes, and pre-meiotic spermatogonia. During early ovarian differentiation, immunoreactive Scp3 was not detected in the gonads of ricefield eels at 6 days post-hatching (dph) but was found to be abundantly localized in the cytoplasm of some oogonia at 7 dph, coinciding with the appearance of the ovarian cavity and ovarian differentiation. At 14 dph, strong Scp3 immunostaining was detected on one side of the nucleus with a distinct polarity in some germ cells, presumably at the leptotene stage. Consistent with these results, the expression of scp3 mRNA was faintly detected in the gonads of ricefield eels at 6 dph, increased at 8 dph, and then remained relatively high thereafter. Taken together, these results suggest that the appearance of immunoreactive Scp3 in oogonia could be a marker for early ovarian differentiation in ricefield eels. The translocation of the Scp3 protein from the cytoplasm to the nucleus in the oogonium of ricefield eels appears to be a controlled process that warrants further study.  相似文献   

17.
Histological changes of the digestive tract were studied in shi drum (Umbrina cirrosa) from hatching until 41 days post hatching (dph), when the fry had a mean (±S.D.) total length (TL) of 32 ± 2 mm and wet weight (WW) of 0.42 ± 0.07 g. Larvae were reared using the mesocosm technique, the most natural among commercially employed rearing methods for marine larvae. Shi drum opened their mouth at 2 dph (2.78 ± 0.09 mm TL), at which time 90% of the larvae already had an inflated swim bladder. The differentiation of the digestive tract into buccopharynx, esophagus, and anterior and posterior intestine was completed by 3 dph (2.82 ± 0.07 mm TL), 1 day after the onset of exogenous feeding. The alimentary canal started coiling and formed its first loop at 2 dph, while the pancreas and liver were differentiated at 3 dph. Yolk sac reserves lasted until 7 dph (4.3 ± 0.1 mm TL), suggesting a brief period of endogenous and exogenous feeding. The first esophageal goblet cells appeared at 7 dph containing acid mucins and at 8 dph taste buds appeared on the buccopharyngeal epithelium. The stomach was morphologically differentiated at 9 dph (5.5 ± 0.1 mm TL) when gastric glands became abundant in the cardiac region, and the first pyloric caeca appeared at 14 dph (10.1 ± 0.9 mm TL). Supranuclear eosinophilic vacuoles were observed in the posterior intestine between 3 and 11 dph (6.3 ± 0.9 mm TL). Their number decreased as the stomach differentiated, suggesting a change in the protein digestion mechanism. The results of the study suggest a rapid development of shi drum and its digestive system and underline the possibility of weaning larvae to artificial feed even earlier than the 12 dph employed in the present study.  相似文献   

18.
Eggs of European hake (Merluccius merluccius L.) were stripped from fish caught at sea. Larvae were kept under semi‐intensive conditions at around 12°C. In addition, eggs were incubated in single wells at 9.2, 12.7 and 14.5°C, where hatching, development and survival were closely examined. During the larval stage, a total of 299 larvae were sampled to follow development and growth. In addition a small number of juveniles were sampled. Larvae hatched approximately 4 days after fertilization, and were 2.9 mm in total length (TL). At 6‐day post hatching (dph), the larvae were 4.1 mm (TL), the jaw apparatus was developed, and the larvae had started to feed. Most of the growth during the early larval period is restricted to the head, and there is almost no increase in length for the first 3–4 weeks post hatching. Teeth and pelvic fins appear at 25 dph. Development of unpaired fins at approximately 30 dph marks the start of the larval–juvenile transition. Weaning to formulated feed was accomplished 50 dph, when external morphology was similar to that of adult hake.  相似文献   

19.
以塑膜大棚内养殖的不同龄的中华鳖为试验材料,观察其性腺形态学和组织学的变化,并用酶联免疫吸附法测定血清中睾酮和雌二醇的含量。研究发现,塑膜大棚内中华鳖不仅生长速度加快,而且性腺发育也提前。大棚内养殖的中华鳖的性腺质量和性腺指数明显大于露天池塘养殖的同等鳖龄的中华鳖的性腺质量和性腺指数。半年龄鳖精巢的曲细精管中填塞精原细胞;1龄鳖的精巢,曲细精管中精原细胞2~3层,分布较散;2龄鳖的精巢,生精上皮层数很多,包括精原细胞、初级与次级精母细胞、精子细胞,并且已见圆形精子细胞和拉长的精子出现在管腔中;3龄鳖的精巢,管腔明显增大,生精上皮比2龄鳖的生精上皮层数少,可见靠近基膜的极少量精原细胞、初级与次级精母细胞,变态后的精子细胞的数量最多。半年龄鳖的卵巢内卵泡已经发育至初级卵泡期,1龄鳖的卵泡处于生长卵泡期,2龄鳖的卵巢处于卵黄发生期,3龄鳖处于排卵期。雄性鳖的睾酮的峰值出现于2龄鳖,即生精活动的旺盛期;雌性鳖的睾酮峰值出现于1龄时,即卵泡的生长期;而2龄、3龄的雌鳖的睾酮含量明显降低,即在卵黄形成期和排卵期,睾酮含量是降低的。雌性鳖的雌二醇,在3龄时即卵黄的沉积期和成熟卵的形成期达到最高值。雄性鳖的雌二醇,在2龄时出现最高值,此时生精活动最为旺盛。  相似文献   

20.
Development of the thyroid gland of the Japanese eel (Anguilla japonica) was studied with the use of tank-reared fish. A single thyroid follicle was first found in larvae at 29 days post hatching (dph), total length (TL) 12 mm. Until reaching 25 mm in TL (100 dph), leptocephali had one or two follicles per individual. The inner colloid of the follicles was weakly immuno-positive against the anti-thyroxine (T4) antibody. The number of thyroid follicles and the immunoreactivity later increased as the larvae grew. Thyroid hormones (TH) T4 and triiodothyronine (T3) were not detected in premetamorphic larvae by radioimmunoassays, but became detectable during metamorphosis. The maximum level of T4 was seen in fish at the end of metamorphosis and in just-metamorphosed juveniles, whereas T3 reached the highest level during metamorphosis and declined toward the end of metamorphosis. The results indicated that the thyroid gland first became active during metamorphosis in the development of eel.  相似文献   

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