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1.
Localization of a putative epiboly-determining factor in oocytes of the goldfish (Carassius auratus)
It is unknown whether cytoplasmic determinants in goldfish eggs are asymetrically localized before maturation. In this study
fully grown goldfish oocytes with intact germinal vesiles (GVs) were ligated with baby hair loops along desired planes into
two parts, matured in vitro, and inseminated. Embryos developed from the animal halves with GV of oocytes ligated along the
equator were unable to undergo epiboly, while those developed from the GV-containing parts of oocytes ligated along the animal-vegetal
axis were able to. Also, embryos developed from the animal halves obtained from fertilized eggs could undergo epiboly. From
these results, it was postulated that the goldfish's premature oocyte possessed a putative factor in the vegetal hemisphere
which was responsible for epiboly of the embryonic cells.
This work was supported by the NSFC and the “Climb Plan B” (PD-B6-1-1) of the Chinese Commission of Science and Technology.
Contribution No. 2915 from the Institute of Oceanology, Chinese Academy of Sciences. 相似文献
2.
Fertilized goldfish eggs were dechorionated with a pair of forceps and were cut off along or a little above the equator into
animal and vegetative parts at desired stages with a glass needle or ligated into two connected fragments before cleavage
with baby hair loop. Some of the ligated eggs were detached by further fastening soon after ligation, and some released later
at different stages (2-cell, 16-cell, 128-cell, 512-cell, mid-blastula) to let the organ-forming substance (OFS) enter the
blastoderm. The cholinesterase (ChE) in the resulting embryos was assayed. The results are as follows. 1. All the 142 embryos
developed from the animal hemispheres cut off or ligated off before cleavage gave rise to hyperblastula in which no ChE activity
was observed. 2. All 50 embryos obtained from animal halves isolated at the 8-cell stage produced ChE. 3. Embryos developed
from the eggs released before the 512-cell stage formed ChE, but the later the releasing of the hair knots, the smaller the
number of ChE-producing embryos. 4. After the 512-cell stage (excluding this stage), neither ChE nor tissue differentiation
occurred in the embryos developed from the unfastened eggs though their OFS flow was set free. Since ChE is thought to be
a muscle-specific enzyme in the early developmental stage, it is concluded that the OFS in goldfish egg appears to be indispensable
for the establishment of the mesoderm.
Contribution No. 1507 from the Institute of Oceanology, Academia Sinica 相似文献
3.
Starfish oocytes with intact germinal vesicles (GVs) were cut along desired planes with glass needles or ligated using silk
thread loops into two parts and allowed to mature in vitro, and inseminated. The experimental results showed that (1) only
the parts with GVs or partial GV contents (PGVCs) cleaved, those without any GV materials did not; but nucleated and non-nucleated
fragments cut from mature eggs were able to divide; (2) the development of animal parts of oocytes containing GVs or PGVCs
was like that of animal fragments of matured oocytes with female pronuclei; most of them gave rise to permanent blastulae,
and just a few formed ectodermal vesicles with a little primary mesenchyme; (3) a large part of vegetal fragments with GVs
or PGVCs, and the vegetal parts of mature eggs without female pronuclei developed into small but normal embryos; (4) the fragments
containing GVs or PGVCs obtained from the oocytes along a plane parallel to the animal-vegetal (A-V) axis developed as normally
as the halves (with or without female pronuclei) severed from mature eggs along the same axis. Based on the data above, it
was concluded that (1) the non-chromatin materials in the oocyte GVs are indispensable for successful fertilization and cleavage
of starfish eggs; (2) some factor (s) located asymmetrically in the vegetal hemispheres of starfish oocytes is (are) responsible
for formation of the archenteron and primary mesenchyme. It is evident from the above findings that the oocyte cytoplasm of
the starfish had already regionalized before the GV break-down.
Contribution No. 1722 from the Institute of Oceanology, Academia Sinica 相似文献
4.
泥鳅未受精卵先在合成卵巢液、郝氏液中分别浸泡15、20、30min,然后再受精孵化,统计发育情况,结果表明,合成卵巢液可有效延缓未受精卵遇水后被激活的时间,郝氏液对延缓未受精卵被激活也有一定作用,但效果比合成卵巢液差。用合成卵巢液配制不同浓度胰酶处理受体卵进行细胞电融合实验,胰酶质量浓度为5 mg/mL时,融合卵发育至囊胚期的比例比对照组(郝氏液)高2%,统计分析表明该差异是显著的(P<0.05);但发育至原肠期及孵出期的比例则与对照组无显著差异。胰酶质量浓度为2和1 mg/mL时,融合卵发育到各阶段的比例均低于对照组,统计分析表明两者的差异是显著的(P<0.05)。研究表明,溶液种类、胰酶浓度等对电融合卵的发育有明显的影响,但延缓受体卵的激活时间并不能提高电融合卵的出苗率。用郝氏液配制的2 mg/mL的胰酶溶液处理受体卵,可获得较高比例的融合鱼。 相似文献
5.
ＩＮＴＲＯＤＵＣＴＩＯＮＫｎｏｗｌｅｄｇｅｏｆｇａｍｅｔｏｇｅｎｅｓｉｓｉｎｖａｌｕａｂｌｅｍａｒｉｎｅａｎｉｍａｌｓｉｓｖｅｒｙｉｍｐｏｒｔａｎｔｔｏｃｏｍｍｅｒｃｉａｌｆｉｓｈ ｅｒｙ.Ｇａｍｅｔｏｇｅｎｅｓｉｓｉｎｂｉｖａｌｖｅｓｗａｓｅｘｔｅｎｓｉｖｅｌｙｓｔｕｄｉｅｄａｔｄｉｆｆｅｒｅｎｔｌｅｖｅｌｓ (Ｄｏｈｍｅｎ ,1 983 ;ＤｏｒａｎｇｅａｎｄＬｅＰｅｎｎｅｃ ,1 989ａ,ｂ) .Ｓｃａｌｌｏｐｓａｎｄｏｔｈｅｒｍａｒｉｎｅｂｉｖａｌｖｅｓｈａｖｅｓｉｍｉｌａｒｒｅｐｒｏｄｕｃｔｉｖｅｃｙｃｌｅ… 相似文献
6.
Wang Renxue Wu Xianhan Zhou Jing Zhang Shicui Ma Yingjie Wu Shangqin Shi Yingxian 《中国海洋湖沼学报》1991,9(1):88-93
Full maturation of goldfish oocyte was inducedin vitro by 17 α-hydroxy-20β-dihydroprogesterone. The oocyte maturation involves GV migration to the periphery of the oocyte and germinal
vesicle breakdown (GVBD). In the experiment, incubation duration for GVBD varied in different broods of oocytes. Generally,
if the duration for GVBD was shorter than 6 h, oocytes would have a better chance to survive after maturation and insemination.
The maturation of nucleus (GV) and cytoplasm are not synchronous. Cytoplasm maturation occurs several hs after GVBD. Oocytes
inseminated 8–9 h after GVBD have the highest fertilizing and hatching rate. Fertilized ova maturedin vitro can develop to sexually mature adults capable of reproduction.
Contribution No 1731 from the Institute of Oceanology, Academia Sinica. 相似文献
7.
8.
DHANEESH Kottila Veettil AJITH KUMAR Thipramalai Thankappan SWAGAT Ghosh BALASUBRAMANIAN Thangavel 《中国海洋湖沼学报》2012,30(4):528-534
Breeding and mass scale larval rearing of clownfish Amphiprion percula is very limited in brackishwater. We designed an indoor program of A. percula culture in brackishwater with a salinity of 24±1, during which the impacts of feed type, water temperature, and light intensity, on the efficiency of its reproduction, were revealed. The fish were accommodated along with sea anemones in fibre glass tanks to determine the influence of brooder diet on breeding efficiency. Higher reproductive efficiency [number of eggs laid (276 22.3 eggs)] was observed when fish were fed live Acetes sp. rather than clam (204 16.4 eggs), trash fish (155 12 eggs) and formulated feed (110 10 eggs). The spawning rate was increased during September and October (water temperature, 28.74 0.55°C) on average of 2.4 spawning per month; and low spawning rate was in January (water temperature, 24.55 0.45°C) on average of 1 spawning per month. Among three light intensities (100, 500, and 900 lx) set to evaluate larval survival rate, larvae showed the highest survival rate (65.5%) at 900 lx. The breeding method specifically in brackishwater developed in the present study is a new approach, will help the people from the regions of estuary and backwater to enhance their livelihood and it will lead to reduce the exploitation from the wild habitat. 相似文献
9.
ＩＮＴＲＯＤＵＣＴＩＯＮＡｍｐｈｉｏｘｕｓｏｒｌａｎｃｅｌｅｔ,ａｃｅｐｈａｌｏｃｈｏｒｄａｔｅ,ｈａｓｌｏｎｇｂｅｅｎｒｅｇａｒｄｅｄａｓｔｈｅｌｉｖｉｎｇｉｎｖｅｒｔｅｂｒａｔｅｍｏｓｔｒｅｓｅｍｂｌｉｎｇｔｈｅａｒｃｈｅｔｙｐｅｏｆｖｅｒｔｅｂｒａｔｅｓ.Ｉｔｈａｓｂｅｅｎｗｉｄｅｌｙｋｎｏｗｎａｓｏｎｅｏｆｔｈｅｍｏｓｔｉｍｐｏｒｔａｎｔｓｐｅｃｉｅｓｉｎｔｈｅｚｏｏｌｏｇｉｃａｌｗｏｒｌｄ,ａｎｄｈａｓｂｅｅｎｅｍｂｒｙｏｌｏｇｉｃａｌｌｙｓｔｕｄｉｅｄｆｏｒｏｖｅｒ130ｙｅａｒｓ(Ｚｈａｎ… 相似文献
10.
石炭纪处于秦岭南、北板块由俯冲到全面碰撞的重要阶段。在俯冲板块前缘,石炭系发育在两种不同类型的沉积盆地之中。前缘南带盆地的形成与俯冲板块边缘弯曲而导致的浅层水平伸展有关,前缘北带主要为一些小型残余盆地,并明显遭受定向滑移构造的改造。两种不同沉积作用演化是在不同的构造过程中形成的。 相似文献
11.
INTRODUCTIONTidalchannelsareimportantgeomorphologicunitsalongsiltcoasts.Theyhaveanevidentfunc tionfortidalflatbecausetheyareassociatedwithitsrapidbayheadwarderosionandlateralswing ing.Thetidalchannelsdevelopalongthecoastandplayanimportantroleinseaandlandinterac tion .Manyscientistsresearchedthetidalchannels (Bayliss Smith ,1 978;Shao ,1 988;Zhang ,1 995) .TheScientificandTechnicalCommitteeofShandongProvince (1 991 )investigatedthecoastoftheHuanghe (Yellow)RiverDeltaandresearchedtheti… 相似文献
12.
ＩＮＴＲＯＤＵＣＴＩＯＮＢｉｌｌａｒｄ ( 1 986)ｓｔｕｄｉｅｄｔｈｅｓｐｅｒｍａｔｏｚｏｏｎｕｌｔｒａｓｔｒｕｃｔｕｒｅｓｉｎｔｅｌｅｏｓｔｓａｎｄｆｏｕｎｄｄｉｓｔｉｎｃｔｄｉｆｆｅｒｅｎｃｅｓａ ｍｏｎｇｄｉｆｆｅｒｅｎｔｓｐｅｃｉｅｓ.Ｓｔｕｄｙｏｎｓｐｅｒｍａｔｏｚｏｏｎｍｏｒｐｈｏｌｏｇｙａｎｄｆｕｎｃｔｉｏｎｉｓａｃｈａｌｌｅｎｇｅｂｅｃａｕｓｅｏｆｔｈｅｓｐｅｒｍ’ｓｓｐｅｃｉａｌｅｎｖｉｒｏｎｍｅｎｔ (Ｇａｇｅｅｔａｌ.,1 998;ＷａｎｇａｎｄＺｈａｎｇ,1 999) .Ｓｉｎｃｅｌｅｆｔ ｅｙ… 相似文献
13.
ＩＮＴＲＯＤＵＣＴＩＯＮＲｅｓｔｉｎｇｅｇｇｓ,ｔｈｅｐｒｏｄｕｃｔｏｆｓｅｘｕａｌ(ｍｉｃｔｉｃ)ｒｅｐｒｏｄｕｃｔｉｏｎｏｆｍｏｎｏｇｏｎｏｎｔｒｏｔｉｆｅｒｓｌｉｋｅＢｒａｃｈｉｏ ｎｕｓｐｌｉｃａｔｉｌｉｓｏｒＢ .ｒｏｔｕｎｄｉｆｏｒｍｉｓ,ｃａｎｂｅｒｅａｄｉｌｙｓｔｏｒｅｄａｎｄｕｓｅｄｗｈｅｎｎｅｅｄｅｄｔｏｓｔａｒｔｍａｓｓｃｕｌｔｕｒｅｓｆｏｒｔｈｅｐｒｏｄｕｃｔｉｏｎｏｆｌｉｖｅｆｏｏｄｓｆｏｒｌａｒｖｉｃｕｌｔｕｒｅｏｆｍａｒｉｎｅｆｉｓｈｅｓａｎｄｃｒｕｓｔａｃｅａｎｓ.Ｔｈｅ… 相似文献
14.
Histological characteristics of gametogenesis of two kinds of scallops, gonochoric Chinese scallop, Chlamys farreri and hermaphroditic bay scallop, Argopecten irradians were investigated in this study. Spermatogenesis in C. farreri has different developmental stages: spermatogonia, primary spermatocyte, second spermatocyte, spermatid and spermatozoon. A large number of same developmental stage spermatic cells converge at a definite area of the testis. Premeiotic, previtellogenic and vitellogenic oocytes can be found during oogenesis in C. farreri, where oocyte distribution is obviously irregular. The A. irradians gonad consists of two different parts in one individual: one part functions as testis, the other as ovary. Between these two parts is a special appearance area, where a large number of spermatic cells are bound with two layers of acellular substance with many oocytes in it. 相似文献
15.
The developmental fate of the pronuclei in recombined embryos obtained by transplanting the donor nuclei into the non-enucleated eggs remains controversial in the case of fish.In the present study,the nuclei from the loach blastulae were transplanted into non-enucleated zebrafish eggs,the resulting 9 inter-family nuclear transplant embryos developed to larval stages,Although the development timing of the nuclear transplants resembled that of zebrafish,chromosome examination revealed that most of the recombined embryos were diploids with karyotype characteristic of loach,which was also proved by RAPD analysis.Moreover,3 out of the 9 larval fish formed barb rudiments specific to loach.It was therefore concluded that the nuclear transplant larval fish were inter-family nucleo-cytoplasmic hybrids;and that only the donor nuclei were involved in the development of the nuclear transplant embryos,while the pronuclei in the non-enucleated eggs were likely automatically eliminated during the development. 相似文献
16.
Wu Xian-han Zhang Shi-cui Wang Yong-yuan Zhang Bao-lu Qu Yan-mei Jiang Xin-ji 《中国海洋湖沼学报》1994,12(4):289-294
Although amphioxus is widespread in temperate and tropical seas, its population is diminishing because of environmental pollution.
To keep the population of this evolutionarily important animal from diminishing, study on its reproduction and development
is necessary. The main findings in this study on the spawning and fecundity of the amphioxus reared in laboratory and its
larval development are as follows. 1. Water temperature markedly affected the spawning. It spawned only when water temperature
reached 21°C. 2. Spawning of the amphioxus in laboratory was markedly extended. Initially, the amphioxus spawned at about
7:00 PM, but spawning time was postponed as spawning days went on. 3. The number of eggs produced by a female ranged from
1400 to 12800, average of 5800. This also represents the fecundity of the amphioxus because it shedded all eggs within the
ovary at a time. 4. During the first few months of life of the amphioxus, its growth rate changed seasonally. The growth rate
in summer and fall was greater than that in winter. 5. The pelagic larva became a benthic adult after 50 days. 6. The amphioxus
reared in laboratory from fertilized eggs could produce fertile eggs and sperms. These findings can be a foundation for measures
to address the problem of diminishing amphioxus population.
Contribution No. 2274 from the Institute of Oceanology, Chinese Academy of Sciences
This work was supported by CNNSF, and Chinese Academy of Sciences. 相似文献
17.
李喜荣 《地球科学与环境学报》1987,(3)
本文依据传统越流理论导出了第一类越流系统井涌水量组成计算式。通过实例对该式进行了机上验算,并绘制出了相关曲线。该式表明,第一类越流系统井涌水量由含水层弹性释放补给量和补给层越流补给量两部分组成;此两种补给量随抽水时间的延续而变化,前者逐渐减少,后者逐渐增大;含水层的导水系数、释水系数和弱透水层的渗透系数、厚度是影响井涌水量的两大重要因素。 相似文献
18.
广西南宁盆地早第三纪沉积相特征 总被引：1，自引：0，他引：1
本文论述了南宁盆地的地质构造背景和第三纪地层、沉积相、古地理演化特征,其中侧重对沉积相剖析认为:南宁盆地在中生代以来形成的NE、NW向两组断裂的“X”型构造背景条件下,受NEE、NNE向各两条断裂控制呈菱形状的第三纪陆相断陷盆地;沉积相以湖相为主,河流相、洪积相次之。前者可分为滨湖、浅湖、半深湖等3个亚相,尤以浅湖相发育,后二者仅在古新世至始新世早、中期发育并分布在湖盆边缘;盆地演化过程中始新世时曾一度上升遭受剥蚀,致使瓦窑村组与上覆地层呈不整合接触,由古新世→始新世末盆地中心由SW→NE迁移,盆地范围增大趋势。还指出南湖组与凤凰山组、古亭组是同期(始新世早、中期)异相产物,盆地内产褐煤、粘土与石英砂等矿产。 相似文献
19.
研究以江蓠为养殖基质的双齿围沙蚕的配子发生及性腺发育。结果表明:1)根据双齿围沙蚕卵细胞形态特征、内部结构、卵径大小,卵母细胞的发生可划分为第Ⅰ时相(卵原细胞)、第Ⅱ时相(小生长期初级卵母细胞)、第Ⅲ时相(大生长期初级卵母细胞,卵黄形成前期、卵黄形成中期、卵黄形成后期)和第Ⅳ时相(成熟卵母细胞,胶膜形成前期、胶膜形成后期)等4时相;根据各时相卵子的数量变化及体腔中其他结构的形态变化,将雌性性腺分为Ⅰ期卵巢、Ⅱ卵巢、Ⅲ卵巢、Ⅳ卵巢和Ⅴ期卵巢等5个阶段。2)根据双齿围沙蚕体腔内精母细胞的大小、形态和所处的位置,将双齿围沙蚕的精子发生划分为精原细胞、初级精母细胞、次级精母细胞、精细胞和精子;根据各时相精子的形态和数量变化以及体腔中其他组织器官的形态变化,将双齿围沙蚕的雄性性腺划分为Ⅰ期精巢、Ⅱ期精巢、Ⅲ期精巢、Ⅳ期精巢和V期精巢等5个阶段。3)Ⅰ-Ⅳ期的性腺主要包含对应时相的生殖细胞,同时,也存在有少量其他时相的生殖细胞,生殖细胞的发育速度并不完全一致。 相似文献
20.
Induced nest spawning and artificial hatching of the fertilized eggs of mudskipper, Boleophthalmus pectinirostris 总被引：2，自引：0，他引：2
In this study, nest spawning was successfully induced by exogenous hormone injections and seawater flow stimulation, and optimum condition for hatching fertilized eggs of burrow fish mudskipper,Boleophthalmus pectinirostris, was searched. Apart from spawning inside the nests, females also spawned outside the nests. The percentages of spawned nests were 8.0% to 24.2%. Most eggs were observed adhered to the inner wall of the top half of the nest. Fertilization rates of the nest-spawned eggs varied from 17.3% to 80.8% Females could spawn after being artificially confined inside the‘nests with males at ratios of 1:1 or 1:2, but the spawned eggs were not fertilized. Mean hatching rates of artificially fertilized eggs incubated in round plastic buckets were 32.7%-70.6%, and in the net cages, were 4.2%-20.5%, respectively. Mean hatching rates of nestfertilized eggs incubated in the round plastic buckets were 33.6%-76.3%, and in the net cages, were 5.9%-25.2%.Results showed that round bucket incubation was the best way for hatching fertilized eggs of mudskipper.Keeping the hatching seawater flowing is an important way for increasing the hatching rates of the mudskipper fertilized eggs. 相似文献