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1.
The effects of four ions and eight neuroactive compounds on inducing larval settlement of A. japonicus were assessed in the present study. All bioassays were conducted in 60 × 9 mm Petri dishes, each contained 10 mL of the test solution and 10 doliolaria larvae. There were significant inductive effects of K+(10- mmol L-1), NH+4(0.1 mmol L1), GABA(10-3 mol L-1), acetylcholine(10-5 mol L-1), L-DOPA(10-5 mol L-1), norepinephrine(10-5 mol L-1) and dopamine(10-7 mol L-1 and 10-5 mol L-1) on the settlement of sea cucumber larvae. L-DOPA and dopamine are the most efficient chemical cues to induce A. japonicus larvae to settle. The highest percentage of larval settlement was induced by 10-5 mol L-1 L-DOPA and dopamine(33% and 40%) compared to the control(7%). However, Ca2+, Mg2+, choline, serotonin, and epinephrine were less effective on larval settlement at all tested concentrations. This study evaluated the stability and feasibility of chemical cues for larval settlement in different culture systems, which can be applied to improve the hatchery production of this valuable species. 相似文献
2.
LU Sumin BAO Zhenmin LIU Hui FANG Jianguang 《中国海洋大学学报(英文版)》2006,5(2):141-145
3.
We evaluated the effect of pH on larval development in larval Pacific oyster （Crassostrea gigas） and blood cockle （Arca inflata Reeve）. The larvae were reared at pH 8.2 （control）, 7.9, 7.6, or 7.3 beginning 30 min or 24 h post fertilization. Exposure to lower pH during early embryonic development inhibited larval shell formation in both species. Compared with the control, larvae took longer to reach the D-veliger stage when reared under pH 7.6 and 7.3. Exposure to lower pH immediately after fertilization resulted in significantly delayed shell formation in the Pacific oyster larvae at pH 7.3 and blood cockle larvae at pH 7.6 and 7.3. However, when exposure was delayed until 24 h post fertilization, shell formation was only inhibited in blood cockle larvae reared at pH 7.3. Thus, the early embryonic stages were more sensitive to acidified conditions. Our results suggest that ocean acidification will have an adverse effect on embryonic development in bivalves. Although the effects appear subtle, they may accumulate and lead to subsequent issues during later larval development. 相似文献
4.
The effects of temperature and substrate on ontogenetic patterns and settlement behavior of bastard halibut, Paralichthys olivaceus （T. et S.） were studied in a series of laboratory experiments. Analysis on stage-based data revealed that except for settlement, and compared to the substrate, the ambient temperature dominantly controlled the hatch success and subsequent development of the species. The oosperm optimum survival rate of 60% during hatching occurred at 20℃, and survival rate of 29%, at 18℃ for larval rearing. The survival rate of larvae reared under variable temperature of 3.5-4.5℃ was higher than that of those reared under stable temperature. The maximum survival rate of 29%, corresponded to variation at temperature of 4℃. With increase in age newly settled juveniles preferred to lie on the fine substrate and gradually moved on the coarse substrate. GLM （general linear model） analysis showed that the combination of temperature and substrate had no significant impact on the survival of settling larvae, but definitely affected the duration of settlement. 相似文献
5.
Fertilised eggs of the devil stringer(I nimicus japonicus) were incubated at different salinity levels(21, 25, 29, 33, and 37), and then the hatching performances, morphological parameters, and biochemical composition(protein, lipid and carbohydrate) of the larvae were assayed to determine the influence of salinity on the early development of I. japonicus. The tested salinity levels did not af fect the times of hatching or mouth opening for yolk-sac larvae. However, the salinity significantly influenced the hatching and survival rates of open-mouthed larvae, as well as the morphology of yolk-sac larvae. The data indicated that 30.5 to 37.3 and 24.4 to 29.8 were suitable salinity ranges for the survival of embryos and larvae of I. japonicus, respectively. Larvae incubated at a salinity level of 29 had the greatest full lengths, and decreasing yolk volume was positively correlated with the environmental salinity. With increasing salinity, the individual dry weights of newly hatched larvae or open-mouthed larvae decreased significantly. Newly hatched larvae incubated at a salinity level of 29 had the greatest metabolic substrate contents and gross energy levels, while the openmouthed larvae's greatest values occurred at a salinity level of 25. Larvae incubated in the salinity range of 33 to 37 had the lowest nutritional reserves and energy values. Thus, the I. japonicus yolk-sac larvae acclimated more readily to the lower salinity level than the embryos, and higher salinity levels negatively influenced larval growth and development. In conclusion, the environmental salinity level should be maintained at 29–33 during embryogenesis and at 25–29 during early larval development for this species. Our results can be used to provide optimum aquaculture conditions for the early larval development of I. japonicus. 相似文献
6.
Zooplankton constitutes a major part of the diet for fish larvae in the marine food web, and it is generally believed that copepods can meet the nutritional requirements of fish larvae. In this study, calanoid copepod Schmackeria poplesia, rotifer Brachionus plicatilis and anostraca crustacean Artemia sp. were analyzed for fatty acid contents, and were used as live food for cul- turing larval Japanese flounder, Paralichthys olivaceus. The total content of three types of HUFAs （DHA, EPA and ARA） in S. po- plesia was significantly higher than that in the other two live foods （P〈O.O1）. Three live organisms were used for raising larvae and juveniles of Paralichthys olivaceus respectively for 15 and 10 d. Then the growth, survival and fatty acid composition of the larvae and juveniles were investigated. The results showed that the larvae and juveniles fed with copepods （S. poplesia） had significantly higher growth rate than those fed with the other two organisms （P〈0.01）. The survival of the flounder larvae fed with copepods was significantly higher than that of the others （P〈0.01）, and the survival of the juvenile fish fed with copepods was higher than that fed with Artemia （P〈0.05）. The contents of three types of HUFAs （DHA, EPA and ARA） and the ratio of DHA/EPA in larval and juve- nile flounder P. olivaceus were analyzed. The results showed that the contents of DHA, EPA and ARA in the larvae and juveniles fed with S. poplesia were higher than those fed with a mixed diet orArtemia only, and the ratio of EPA/ARA in larvae and juveniles of P. olivaceus fed with S. poplesia was lower than that in the case of feeding with a mixed diet or Artemia only. The present data showed that copepod is the best choice for feeding the larvae and juveniles of fish considering its effects on the survival, growth and nutrition composition of the fish. 相似文献
7.
Abalone Haliotis diversicolor supertexta is an important economic mollusk. The settlement and metamorphosis are two critical stages during its development period, which has direct influence on abalone survival and production. The influence of reactive oxygen species （hydrogen peroxide） on abalone embryo and juvenile development were examined in this study. Larvae of Haliotis diversicolor supertexta were induced to settlement and metamorphose by exposure to seawater supplemented with hydrogen peroxide. They had the best performance at 800 μmol/L. The concentration of 1 000 μmol/L or higher was toxic to the larvae, as the larvae could settle down only at benthic diatom plates without complete metamorphosis. In addition, H2O2 adding time was critical to the larval performance. 24h after two-day post-fertilization was proved to be the optimal adding time. In this paper, two action mechanisms of hydrogen peroxide are discussed： （1） hydrogen peroxide has direct toxicity to ciliated cells, thus cause apoptosis; （2） hydrogen peroxide, as a product from catecholamines＇ autoxidation process in vivo, can reverse this process to produce neuro-transmitters to induce abalone metamorphosis. 相似文献
8.
《中国海洋湖沼学报》2017,(1)
Sumithion is widely used to control brittle in paddy fields and tiger bug in fish larval rearing ponds. The objective of this study was to elucidate the toxic effects of sumithion on larval stages of stinging catfish Heteropneustes fossilis. Larvae were exposed to two concentrations(150 and 250 μg/L) of sumithion with one control in three replicates of each. Larvae samples were collected at 20- and 24-h intervals followed by observation under a digital microscope. Exposures of stinging catfish larvae to sumithion produced deformities including irregular head shape, lordosis, yolk sac edema, body arcuation, tissue ulceration, etc. The mortality rates of larvae were significantly increased in response to increase in sumithion concentrations. Furthermore, around 30% of the total adult stinging catfish reared in sumithiontreated aquaculture ponds were found to be deformed permanently. These findings highlight that exposure of stinging catfish to sumithion at the critical and sensitive stages in their life cycle may significantly reduce the number of returning adults. Therefore, the use of sumithion for crop protection needs to be considered carefully and alternatives to sumithion should to be developed for controlling aquatic insects in aqua-ponds during larval rearing. 相似文献
9.
Abalone Haliotis diversicolor supertexta is an important economic mollusk.The settlement and metamorphosis are two critical stages during its development period,which has direct influence on abalone survival and production.The influence of reactive oxygen species(hydrogen peroxide) on abalone embryo and juvenile development were examined in this study.Larvae of Haliotis diversicolor supertexta were induced to settlement and metamorphose by exposure to seawater supplemented with hydrogen peroxide.They had the best performance at 800 μmol/L.The concentration of 1 000 μmol/L or higher was toxic to the larvae,as the larvae could settle down only at benthic diatom plates without complete metamorphosis.In addition,H2O2 adding time was critical to the larval performance.24h after two-day post-fertilization was proved to be the optimal adding time.In this paper,two action mechanisms of hydrogen peroxide are discussed:(1) hydrogen peroxide has direct toxicity to ciliated cells,thus cause apoptosis;(2) hydrogen peroxide,as a product from catecholamines' autoxidation process in vivo,can reverse this process to produce neuro-transmitters to induce abalone metamorphosis. 相似文献
10.
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
11.
This study examined the distribution and elimination of Norfloxacin(NFLX) in Fenneropenaeus chinensis ovary and egg and newly hatched larvae.Mature parental shrimp were exposed to 4 or 10 mg L 1NFLX for 2 or 5 d.Ovary and eggs of the shrimp were sampled after spawning in order to detect NFLX residue using high-performance liquid chromatography(HPLC).Results showed that NFLX residue accumulated in F.chinensis eggs after the parental exposure,with the highest residue detected in ovary.To examine the fate of NFLX residue in larvae,we further determined the concentration of NFLX residue in F.chinensis eggs and larvae at 4 different developmental stages after 24-h exposure.From the newly metamorphosed larvae(0 h post-metamorphosis,h.p.m),samples were taken at different time intervals to 72 h.p.m.HPLC assay showed that the concentrations of NFLX residue in zoea exposed to 4 and 10 mg L 1NFLX were the highest at 1.5 h,i.e.,0.332 and 0.454 μg g 1,respectively.At the two NFLX exposure levels,the elimination time of half NFLX(half life) in nauplius was 45.36 and 49.85 h,respectively,followed by that in zoea(31.68 and 33.13 h),mysis larvae(42.24 and 47.28 h) and postlarvae(24.48 and 30.96 h).Both NFLX exposure levels had a germicidal effect.The distribution and elimination of NFLX residue in F.chinensis tissue,eggs and larvae correlated well with the drug exposure level.The disappearance of NFLX residue coincided with the larval growth,and the half-life of NFLX decreased with the larval development. 相似文献
12.
YAN Fajun TIAN Xiangli DONG Shuanglin 《青岛海洋大学学报(英文版)》2014,(5):805-810
The effect of a potential probiotic on the growth performance and immune response of sea cucumber（Apostichopus japonicus） was investigated. Bacillus baekryungensis YD13 isolated from sea cucumber culturing ponds was added to sea cucumber basal feed as a probiotic in different doses（0, the control; 1×10^4（YD134）, 1×10^6（YD136） and 1×10^8（YD138） CFU g-1 of diet）, and administered orally to A. japonicus（initial mean wet weight 5.44 g ± 0.17 g）. The sea cucumbers were fed in 20 aquaria, 5 each treatment, for 60 d. At the end of growth trial, 20 sea cucumbers from each treatment were challenged with Vibrio splendidus. A. japonicus in YD134 and YD136 exhibited significantly better growth performance than control（P 〈0.05）. Five non-specific immune parameters including lysozyme, acid phosphatase, alkaline phosphatase, superoxide dismutase and catalase in coelomic fluid were measured to evaluate the immune response of A. japonicus to the probiotics. Results showed that all parameters were significantly improved when YD11 was supplemented in the dose of 1×10^6 CFU g^-1（P 〈0.05）. The cumulative incidence and mortality after the Vibrio splendidus challenge decreased significantly in sea cucumbers of YD136. Accordingly, 1×10^6 CFU g^-1 of YD13 in diet was recommended for the growth promotion and immune enhancement of A. japonicus. 相似文献
13.
Phospholipids are used to improve the growth and survival of Portunus trituberculatus,a widely cultured crab species in China.However,only total phospholipids or several classes are applied in crab diets.In this study,we employed a targeted lipidomic method to investigate the comprehensive phospholipid composition in P.trituberculatus larvae and reveal the changing phospholipid profile over the larval development.Results showed that P.trituberculatus larvae contain 112 phospholipid species belonging to 10 phospholipid classes,in which phosphatidylcholine(PC)and phosphatidylethanolamine(PE)species are the most abundant,and PC,PE,phosphatidic acid,and phosphatidylserine(PS)are with high concentrations.The levels of all phospholipids significantly changed with larval development,which was highlighted by the downward parabolic changes in PE,phosphatidylglycerol,phosphatidylino-sitol,PS,lysophosphatidic acid,and sphingomyelin levels.In addition,nearly all phospholipid species were depleted at the M stage,which probably contributed to the mass mortality of crab larvae.These findings on the composition and alterations of phospholipids in P.trituberculatus larvae provide novel perspectives for the targeted supplementation of phospholipids in crab diets.Our work also highlights the use of targeted UHPLC-MS lipidomics in understanding the changes of phospholipids during crab development. 相似文献
14.
The experimental results showed that:1) The embryonic development of bay scallop is inhibited ata dissolved oxygen range of 1.38-3.64×10~(-3)at 23℃,and completely blocked below the lower limit.2)The tolerance of larvae to anoxia increased with larval sizes and was related to their oxygen debt.3)The scallop larvae exhibited specific behavioral responses to oxygen deficiency,which finally led tovelum disintegration and larval death.The possible relationship between environmental oxygen deficien-cy and the disease of disintegration of the larval Velum is also discussed.In this study,considerableoxygen debt was found in bay scallop larvae,which was greater in small animals.Based on the worksof previous authors,a new concept is proposed for the estimation of oxygen debt,namely,thecompensatory rate of oxygen debt(CROD).This can be used in intra-or interspecific comparison ofoxygen debt.The results can be helpful in the management of water quality and for the prevention oflarval diseases encountered in scallo 相似文献
15.
WANG Xinxia MAI Kangsen 《中国海洋大学学报(英文版)》2005,4(3):267-271
A 13-day feeding trial was carried out to evaluate the effectiveness of a microbound diet for rearing the larvae of Chinese shrimp Fenneropenaeus chinensis in comparison with the live foods that consist of Isochrysis galbana, Chlorella vulgaris, Tetraselrnis chuii, rotifer （Brachionus plicatilis） and Arternia sp. Larvae of 0 to 13d post-hatch （dph） were reared in a temperature-controlled semi-open culture system and stocked at a density of 100 larvae L^-1 in tanks, each containing 50 L sterilized seawater with salinity 30-32. Larvae were manually fed either the live foods or the microbound diet 6 times per day. At 13 dph, the growth of the larvae fed on the microbound diet was approximately 84% of that fed on the live foods. The survival rate of the larvae fed on the microbound diet was 44.29% at 13dph, which was not significantly different from that of larvae fed on live foods （63.55%）. The body length and development index （DI） of the larvae fed on the microbound diet were always lower than those of larvae fed on live foods. However, the differences reached significant levels only at 11 and 13 dph （P〈 0.05）. The mean dry weight loss of the microbound diet was 9.2% after 90 min immersion in seawater, indicating that this diet has a good water stability. The microbound diet contains 52.23% crude protein and 10.27% lipid and is easy to prepare. These characteristics of the diet suggest good potentials for its successful use in the larviculture of other penaeid and fish species. 相似文献
16.
《中国海洋湖沼学报》2016,(6)
A bstract The venerid clam(M actra veneriformis Reeve 1854) is one of the main cultured bivalve species in intertidal and shallow subtidal ecosystems along the west coast of Korea. To understand the effects of ocean acidifi cation on the early life stages of Korean clams, we investigated shell growth and abnormality rates and types in the D-shaped, umbonate veliger, and pediveliger stages of the venerid clam M. veneriformis during exposure to elevated seawater pCO_2. In particular, we examined abnormal types of larval shell morphology categorized as shell deformations, shell distortions, and shell fi ssures. Specimens were incubated in seawater equilibrated with bubbled CO_2-enriched air at(400±25)×10~(-6)(ambient control),(800±25)×10~(-6)(high pCO_2), or(1 200±28)×10~(-6)(extremely high pCO_2), the atmospheric CO_2 concentrations predicted for the years 2014, 2084, and 2154(70-year intervals; two human generations), respectively, in the Representative Concentration Pathway(RCP) 8.5 scenario. The mean shell lengths of larvae were signifi cantly decreased in the high and extremely high pCO_2 groups compared with the ambient control groups. Furthermore, under high and extremely high pCO_2 conditions, the cultures exhibited signifi cantly increased abundances of abnormal larvae and increased severity of abnormalities compared with the ambient control. In the umbonate veliger stage of the experimental larvae, the most common abnormalities were shell deformations, distortions, and fi ssures; on the other hand, convex hinges and mantle protuberances were absent. These results suggest that elevated CO_2 exerts an additional burden on the health of M. veneriformis larvae by impairing early development. 相似文献
17.
吕延田 《中国海洋湖沼学报》1989,(4)
The 48-h straight-hinge larvae of Argopecten irradians were exposed for 9 days to various concentrations of zinc in seawater. The growth rate of larvae in the 50 ppb Zn mediums was 77% that of the controls, and nearly zero in the 200 ppb Zn mediums. A progressive decrease in growth and increase in larval deformity and mortality was observed with increasing zinc concentrations from 50 to 200 ppb. 50 and 100 ppb Zn resulted in delayed development of eye spot and metamorphosis and reduced numbers of larvae at both stages. All larvae subjected to higher zinc concentrations died before attaining the eye-spot stage. The zinc concentrations which caused 50% reduction in growth (G C50)and 50% mortality (LC 50)were 109 and 120 ppb respectively. Growing in the medium with 100 ppb Zn, the larvae fed with Isochysis galbana cultured in a medium with 100 ppb Zn showed more suppressed growth and development than those fed with nonnal food. It is suggested that zinc contaminated food has strong influence on the bay sca 相似文献
18.
HUO Zhongming ;WANG Zhaoping ;LIANG Jian ;ZHANG Yuehuan ;SHEN Jianping ;YAO Tuo ;SU Jiaqi ;YU Ruihai 《青岛海洋大学学报(英文版)》2014,(4):666-670
This study examined the effects of salinity on embryonic development,survival,and growth of the Hong Kong oyster Crassostrea hongkongensis.The embryos,larvae,and juveniles of C.hongkongensis were held in artificial seawater at three different salinities （low,15; medium,23; and high,30） to determine the optimum hatchery and nursery conditions for mass production of the seeds.Results showed that the percentage production of straight-hinged larvae from fertilized eggs was significantly lower at the high salinity than at the low-and medium-salinities （P ＜ 0.05）.The survival rates of larvae and juveniles differed significantly among the three salinity trials,with the highest survival rate observed at the low salinity （P＜ 0.05）.The shell height of larvae was significantly larger at the low salinity than at the high and medium salinities from days 9 to 15 （P＜ 0.05）,whereas that of juveniles was significantly larger at the low salinity than at the high and medium salinities on day 70 （P ＜ 0.05）.These results indicate that the larvae and juveniles of C.hongkongensis are tolerant to a wide range of salinities （15 to 30）,but show better growth and survival at relatively low salinities.Thus,it is recommended to use relatively low salinities in hatchery and nursery systems for improved yields of C.hongkongensis. 相似文献
19.
Lü Fu 《中国海洋大学学报(英文版)》2008,7(1):77-82
The effects of salinity on hemolymph osmotic pressure, Na^＋ concentration and Na^＋-K^＋-ATPase activity of gill of Chinese crab Eriocheir sinensis were studied. The results showed that hemolymph osmotic pressure and Na^＋ concentration increased significantly （P〈0.05）, and the Na^＋-K^＋-ATPase activity of gills decreased significantly （P〈0.05） when salinity increased from 0 to 16. The hemolymph osmotic pressure and Na^＋ concentration in each treatment group rose remarkably at 0.125 d or 0.25 d, while the Na^＋-K^＋-ATPase activity of gill reduced gradually with increased experiment time in 3 d. Then the three parameters remained at a constant level after 0.25 d, 0.125 d and 3 d, respectively, and higher hemolymph osmotic pressure, higher Na^＋ concentration and lower Na^＋-K^＋-ATPase activity of gill occurred at higher salinity. The effect of salinity change on protein concentration of hemolymph was indistinct （P〉0.05）; However, the protein concentration decreased gradually with the increase of salinity from 0.25 d to 1d, and then tended to be stable from day 1 to day 15. 相似文献
20.
In this study, we evaluated the effects of CO_2-induced seawater acidification on fertilization, embryogenesis and early larval development in the sea urchin Glyptocidaris crenularis, that inhabits subtidal coastal areas in northern China. The range in seawater p H used in experiments was based on the projections of the Intergovernmental Panel on Climate Change(IPCC), to the year 2100. A natural seawater treatment(p H_(nbs) =7.98±0.03) and three laboratory-controlled acidified treatments(OA_1, ΔpH_(nbs) =-0.3 units; OA_2, ΔpH_(nbs) =-0.4 units; OA_3, ΔpH_(nbs) =-0.5 units) were used in experiments. Results show that:(1) there was a negative effect of seawater acidification on fertilization and on the percentage of abnormal fertilized eggs;(2) the size of early cleavage stage embryos decreased in a dose-dependent manner with decreasing p H;(3) both the hatching rate of blastulae and the survival rate of four-armed pluteus larvae decreased as pH declined;(4) larval abnormalities including asymmetrical development, changes in the length of skeletal elements, and corroded spicules were observed in all seawater acidified-treatments compared with the control. These data indicate that seawater acidification has a negative impact on the early development of G. crenularis, and supports the hypothesis that the response of echinoderms to ocean acidification(OA) varies among species. Further research is required to clarify the specific cellular mechanisms involved. 相似文献