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1.
PAN Ying LI Qi YU Ruihai WANG Rucai 《中国海洋大学学报(英文版)》2008,7(1):103-107
Sperm nuclear expansion, meiosis and the association of the male and female pronuclei leading to the four-cell stage in normal Chlamysfarreri eggs were observed under a fluorescence microscope. The effects of ultraviolet （UV） irradiation on the fertilizing sperm were also examined. Both normal and UV-irradiated sperm nuclei enlarged at three distinct phases （phase A, metaphase I; phase B, polar body formation; and phase C, female pronuclear development and expansion） that were temporally correlated with meiotic process of the maternal chromosomes. Sperm nuclei underwent a rapid, initial enlargement during phase A, but condensed slightly during phase B, then re-enlarged during phase C. The effects of UV irradiation were not apparent during transformation of the sperm nucleus into a male pronucleus, and there was not any apparent effect on meiotic maturation and development of the female pronucleus. However, the rate of expansion of the UV-irradiated sperm nuclei and the size of male pronuclei were reduced apparently. Unlike the female pronucleus, the male pronucleus derived from sperm genome inactivated by UV irradiation did not form chromosomes, but became a dense chromatin body （DCB）. At mitotic anaphase, DCB did not participate in the karyokinesis of the first cleavage as evidenced by chromosomal nondisjunction, demonstrating the effectiveness of using UV irradiation to induce gynogenetic scallop embryos. 相似文献
2.
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
3.
INTRODUCTIONTriploidanimalsareusefulbecausetheyaresterile ,characterizedbypositivegrowthinthere productiveseason ,usefulfortesting ,forintroductionofnon nativespecies ,andforprotectionofde velopedstrains.Theinductionoftriploidyhadbeenreportedinmanyaquaculturespecies .Triploidshavebeensuccessfullyinducedinshrimpusingtemperatureshockorchemicalshock (CB ,6 DMAP)in 4species :Sicyoniaingentis (Xiangetal.,1 991 ) ,Fenneropenaeuschinensis (Xiangetal.,1 992 ;Daietal.,1 993;Baoetal.,1 993;Li… 相似文献
4.
Loach （Misgurnus anguillicaudatus） is a commercially important fish in China and an ideal aquaculture species. However, culturists experience high larval and juvenile mortality during mass production. To provide insight into ways to improve larviculture techniques, we describe the morphological characteristics and behavior of loach during the larval and early juvenile stages. Yolksae larvae ranged from 2.8 to 4.0 mm body length （BL） between days 0 to 4; preflexion larvae ranged from 3.6 to 5.5 mm BL between days 4 to 6; flexion larvae ranged from 4.8 to 8.1 mm BL between days 5 and 14; and post-flexion larvae ranged from 7. l to 15.7 mm BL between days 11 to 27; the minimum length and age of juveniles was 14.1 mm BL and 23 d, respectively. Loach are demersal from hatch through to the early juvenile stages. A suite of morphological characteristics （e.g., external gill filament and ventral mouth opening） and behavioral traits have developed to adapt to demersal living. We observed positive allometric growth in eye diameter, head length, head height, and pectoral fin length during the early larval stages, reflecting the priorities in the development of the organs essential for survival. Our results provide a basis for developing techniques to improve the survival of larval and juvenile loach during mass production. 相似文献
5.
Effects of base analogues 5-bromouracil and 6-aminopurine on development of zebrafish Danio Rerio 总被引：1，自引：0，他引：1
Zebrafish （Danio rerio） genetic screens allow isolation of a wide array of problems in vertebrate biology. The effects of base analogues 5-bromouracil and 6-aminopurine on the development of zebrafish embryos are reported for the first time in this study. The early development of the zebrafish embryos was little affected by 5-bromouracil and 6-aminopurine, while the late development （organogenesis） was significantly impaired. Embryos exposed to 5-bromouracil mainly showed curled tail, wavy body, golden pigmentation and the mouth with protruding lower jaw. 6-aminopurine-treated embryos had defective anterior structures, curled tails and wavy body. RAPD analysis showed that the majority of 5-bromouracil-and 6-aminopurine-treated larvae and fish shared banding patterns in common with the control, suggesting that most mutagenesis induced by these agents are point mutations. However, some fish derived from 5-bromouracil-treated embryos had golden（gol） pigmentation; and RAPD analysis revealed that their band patterns differed from those of the control.Possibly, 5-bromouracil can occasionally cause relatively extensive changes in the fish genome. The results of this study may provide valuable help for detailed studies of mutagenesis. 相似文献
6.
Zebrafish (Danio rerio) genetic screens allow isolation of a wide array of problems in vertebrate biology. The effects of base analogues 5-bromouracil
and 6-aminopurine on the development of zebrafish embryos are reported for the first time in this study. The early development
of the zebrafish embryos was little affected by 5-bromouracil and 6-aminopurine, while the late development (organogenesis)
was significantly impaired. Embryos exposed to 5-bromouracil mainly showed curled tail, wavy body, golden pigmentation and
the mouth with protruding lower jaw. 6-aminopurine-treated embryos had defective anterior structures, curled tails and wavy
body. RAPD analysis showed that the majority of 5-bromouracil- and 6-aminopurine-treated larvae and fish shared banding patterns
in common with the control, suggesting that most mutagenesis induced by these agents are point mutations. However, some fish
derived from 5-bromouracil-treated embryos had golden (gol) pigmentation; and RAPD analysis revealed that their band patterns differed from those of the control. Possibly, 5-bromouracil
can occasionally cause relatively extensive changes in the fish genome. The results of this study may provide valuable help
for detailed studies of mutagenesis.
This work was supported by Ministry of Science and Technology (MOST) of China (G 1999012005). 相似文献
7.
Triploidy was induced in Chinese shrimpFenneropenaeus chinensis by 30±0.5°C heat shock treatment (initiated at 20 min after fertilization) for 10 min to inhibit the release of PB2 at 18.0°C.
The highest triploid rate obtained was 84.5% in nauplius stage. The effect of heat shock treatment on meiosis and cleavage
of eggs was investigated in this work aimed to establish efficient procedures for triploid induction and to gain understanding
of the mechanism of triploid production. Three pronuclei that could be observed in the treated eggs under fluorescence microscope
developed into triploid embryos. Some abnormal chromosome behavior was observed in heat shocked eggs.
Contribution No. 4407 from the Institute of Oceanology, Chinese Academy of Sciences.
This work was supported by Project under Major State Basic Development Program (G1999012009) and Knowledge Innovation Program
of the Chinese Academy of Sciences (KZCX 2-211) 相似文献
8.
Decreasing fish resources in estuaries is a subject of anthropogenic activities.Studies of the spatiotemporal distribution of fish eggs and larvae can help identify the status and processes underlying recruitment in a fishery.As the fifth largest river estuary in the world,the Huanghe(Yellow)River estuary(HRE)is a typical estuary that has been seriously affected by human activities.Annual surveys on ichthyoplankton and environmental factors were conducted in the months of May of 2005 and 2009-2016 in the HRE to investigate the spatiotemporal distribution of fish eggs and larvae and the associated influencing factors.A total of 23 and 20 species of eggs and larvae,respectively,were collected.The dominant orders were Perciformes(51.2%)and Clupeiformes(25.6%).The average number of fish species eggs and larvae were 6.0 and 4.1 in average abundance of 0.91 and 0.13 ind./m~3,respectively.The dominant species were mainly low-commercial-value small-sized fishes,such as Clupanodon punctatus,Hare,ngula zutnasi,and Acanthogobius,whereas certain traditional commercial fishes,such as Trichiurus lepturus,and Clupea pallasii,were not seen.Analysis of the fish egg and larval community revealed four temporal assemblages and two spatial assemblages.Salinity was the main factor on the spatial distribution of ichthyoplankton communities,the species number and Shannon-Weiner diversity index(H')of the fish egg and larval community near the river mouth with lower salinity were significantly lower than the community far away from the river mouth with higher salinity.In addition,increases of water temperature promoted the number and abundance of fish species eggs,and the areas of abundant prey tended to have a more diversified and abundant of ichthyoplankton species.In overall,overfishing,dam construction,and other human activities were the main drivers that led to the substantial decline in fishery resources in the HRE. 相似文献
9.
10.
波纹龙虾胚胎的离体培养及发育观察 总被引：1，自引：1，他引：0
对波纹龙虾不同发育时期的胚胎进行离体培养和显微观察。结果表明,初始培育的离体胚胎愈接近孵化期,其孵化率愈高(最高达80.0%);波纹龙虾胚胎发育经历受精卵、卵裂期、囊胚期、原肠期、中眼色素形成期、复眼色素形成期、心跳期、破膜前期和出膜期;胚胎在发育过程中颜色变化:橙红→深橙红→砖红→灰白→接近透明。 相似文献
11.
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
12.
盐度对管角螺胚胎发育的影响 总被引：2，自引：1，他引：1
在水温25.5~29.2℃的条件下,设11个盐度梯度对管角螺[Hemifusus tuba(Gmelin)]的胚胎发育进行了观察和研究。结果显示:管角螺胚胎发育的适宜盐度范围为22~35,最适盐度范围为25~31;在适宜的盐度范围内,7~9 d发育的胚胎能完全消耗卵囊内的败育卵变为自身发育的营养物质,13~15 d形成稚螺雏形,31~34 d胚胎完成发育从卵囊内爬出;适宜盐度范围内各盐度对正常卵发育数量、孵化率无显著影响。低于其适宜盐度范围,胚胎发育在初始阶段便受抑制,盐度为16~19只有部分正常卵发育,需34~36 d才完成胚胎发育;高于适宜盐度范围的38、41两组,在6 d内对胚胎发育无影响,但6 d后影响显著。低盐度对胚胎发育影响较高盐度更为明显。 相似文献
13.
观察了珠江斑鳠3批次受精卵的胚胎发育,描述及记录了胚胎发育各期的形态特征及所需时间。斑鳠的成熟卵子呈圆形,黄色,卵子直径为3.1~3.8 mm,吸水后最大卵径为4.0~4.2 mm,受精卵黏性很小。珠江斑鳠胚胎发育与其他硬骨鱼类基本相似,属于盘状卵裂。在水温(27.5±0.5)℃时,受精后约1 h 10 min进入胚盘形成期,受精2 h 15 min后进入卵裂期,受精后7 h 50 min,进入囊胚期,再经约13 h 45 min进入原肠期,受精后21 h15 min,胚孔封闭,当受精39 h 5 min后,心脏开始出现搏动,受精后55 h,仔鱼开始孵出。 相似文献
14.
《中国海洋湖沼学报》2021,(4)
Fish embryos are widely used as models in toxicology,drug development,and human disease research because of their high sensitivity,observability,and operability,providing the basis for an in-depth understanding of the embryogenesis.Increasing studies have indicated that birth defects are hereditary.In this study,we used Oryzias melastigma as a model to conduct a study of 185-day embryogenesis and observed self-induced non-pathological abnormal embryogenesis.O.melastigma experienced pre-puberty stage,adolescence stage,and senescence stage,and individuals produced up to 102 eggs per day.However,the fecundity was markedly reduced during the senescent stage.During the active egg and blastodisc stages,pseudo-fertilization and pseudo-blastocysts were observed.During cleavage at the 4-to 32-cell stages,we observed blastomeres separation or dislocation.Excessively separated blastomeres formed double blastoderms,eventually resulting in conjoined twins.During the blastula stage,we observed abnormally increased cell volume,narrowed and elongated blasto cysts,and ab normally coated blastoderms.At the organogenesis stage,we observed abnormal numbers of Kupffer's vesicles and conjoined twins.Abnormality in the location and number of oil droplets were observed in various development stages.Abnormal development was more commonly observed in fertilized eggs produced by broodstock in prepuberty or senescence stages,which is probably related to the age of fish and the egg quality.This study can provide the materials for comparative analysis in toxicological and molecular studies of O.melastigma,and may provide evidence for other economic fish that produce sticky eggs. 相似文献
15.
Weimin Wang Guangxing Liu Tianwen Zhang Hongju Chen Liao Tang Xuewei Mao 《中国海洋大学学报(英文版)》2016,15(6):1073-1079
To investigate the effects of elevated seawater pCO2 on the early developmental stages of marine benthic calcifying organisms, we exposed the eggs and larvae of Argopecten irradias, an important bivalve species in Chinese aquaculture, in seawater equilibrated with CO2-enriched (1000 ppm) gas mixtures. We demonstrated that elevated seawater pCO2 significantly interfered with fertilization and larval development and resulted in an increased aberration rate. Fertilization in the treatment (pH 7.6) was 74.3% ± 3.8%, which was 9.7% lower than that in the control (pH 8.3) (84.0% ±3.0%). Hatching success decreased by 23.7%, and aberration rate increased by 30.3% under acidic condition. Larvae in acidified seawater still developed a shell during the post-embryonic phase. However, the shell length and height in the treatment were smaller than those in the control. The development of embryos differed significantly at 12 h after fertilization between the two experimental groups. Embryos developed slower in acidified seawater. Nearly half of the embryos in the control developed into D-shaped larvae at 48 h after fertilization, which were considerably more than those in the treatment (11.7%). Results suggest that future ocean acidification (OA) would cause detrimental effects on the early development of A. irradias. 相似文献
16.
Broodstock of Verasper moseri (Jordan and Gilbert) aged 3–4 years old were selected, and reinforced cultivation was conducted to promote maturation under
controlled water temperature and photoperiod conditions. Fertilized eggs were obtained by artificial fertilization, and the
development of embryos, larvae and juveniles was observed continuously. The results showed that the fertilized eggs of V. moseri were spherical, with transparent yolk and homogeneous bioplasm, and had no oil globule inside. The average diameter of the
eggs was 1.77±0.02 mm. The eggs of V. moseri were buoyant in water with salinity above 35. The cleavage type was typical discoidal. Young pigment cells appeared when
olfactory plates began to form. Hatching occurred at 187 h after fertilization at a water temperature of 8.5°C. The newly
hatched larvae, floating on the water surface, were transparent with an average total length of 4.69±0.15 mm. During the cultivation
period, when the water temperature was raised from 9 to 14.5°C, 4-day old larvae showed more melanophores on the body surface,
making the larvae gray in color. The pectoral fins began to develop, which enabled the larvae to swim horizontally and in
a lively manner. On days 7–8, the digestive duct formed. The yolk sac was small and black. The yolk sac was absorbed on day
11. Larvae took food actively, and body length and body height clearly increased. The rudiments of dorsal and anal fin pterygiophores
were discernible and caudal fin ray elements formed on day 19. On day 24, the larval notochord flexed upwards, and the rays
of unpaired fins began to differentiate. Pigment cells converged on the dorsal and anal fin rays, and the mastoid teeth on
the mandible appeared. On day 29, the left eyes of juveniles began to move upwards. Depigmentation began in some juveniles
and they became sandy brown in color on day 37. Most juveniles began to settle on the bottom of the tank. The left eyes of
juveniles migrated completely to the right side on day 50, when the average body length attained 2.5±0.18 cm, and juveniles
accomplished metamorphosis to young. The embryonic and larval characters of several flounder species are compared. 相似文献
17.
As the most widely used plasticizers in the world, phthalate esters (PAEs) are potential endocrine disruption compounds (EDCs). In the present study, the toxicity of dimethyl phthalate (DMP),diethyl phthalate (DEP), dibutyl phthalate (DBP), di (2-ethylhexyl) phthalate (DEHP) on embryogenesis and larvae development of the marine univalve Haliotis diversicolor supertexta was examined in laboratory. The results show that the malformation of embryos appeared during the experiment, such as embryos died or lysed, small transparent flocculent rings studded on the periphery of the embryo, and the larvae could failed to hatch. In embryo toxic test, embryos incubated at the highest concentration of DMP,DEP and DBP solutions showed significantly high abnormal rate compared with the control, while DEHP solutions displayed no significant difference. In larval toxic test, in all concentrations of DMP, DEP and DBP solutions, larval settlement rates were low significantly than that of the control. Similarly, DEHP solutions show nearly no effect on the larval settlement. The order of toxicity on embryos and larvae is DBP>DEP>DMP>DEHP. Being a simple and easy stimulation to indoor spawn, sensitive to environmental factors, and short culture time, the embryos of 1-1. diversicolor supertexta can be used to indicate toxicity of the PAEs. 相似文献
18.
Starvation has important effects on early development of fish. It determines the survival and growth of fish larvae, and plays an important role in the dynamics of fish population and fisheries recruitment, in this review, we discuss the current studies about the effects of starvation on growth and development of fish larval stage. The goals of this review are to understand some adap- tive mechanisms and ecological countermeasures of starved fish larvae and to provide the scientific guideline for exploring early life history processes, evaluating the nutrition condition and growth of larval fish, protecting fish resource and breeding fish larvae. 相似文献
19.
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
20.
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