中华绒螯蟹对盐度变化的适应及其渗透压调节的研究进展

虾、蟹等甲壳动物具有多样的渗透压调节能力,研究虾、蟹的渗透压调节生理及其对盐度等环境因子的适应能力,可以补充和完善虾、蟹的基础生理学资料,同时对指导虾、蟹的人工育苗和养殖实践,如海水品种的淡化养殖等具有重要的参考价值.由于中华绒螯蟹在咸水中进行繁殖和幼体发育,在淡水中长成,其独特的渗透压调节方式成为国内外相关学者关注的...     

中华绒螯蟹亲蟹渗透压调节和抗氧化系统对盐度的响应

探讨了中华绒螯蟹亲蟹血清离子和渗透压对盐度的响应以及肝胰腺抗氧化能力与盐度的关系.设立4个盐度组(盐度6、12、18、24)和1个淡水对照组,检测第4天和第20天时中华绒螯蟹亲蟹血清中Na+、K+、Cl-浓度、渗透压以及肝胰腺超氧化物歧化酶(SOD)、过氧化氧酶(CAT)活性和还原型谷胱甘肽(GSH)、丙二醛(MDA)...     

Growth,osmoregulation and energy budget of rainbow and steelhead trout under different salinity acclimation methods and the best transition size of steelhead trout

In order to meet the demand of salmon market, Chinese scientists and entrepreneurs are working on salmon mariculture far offshore in the Yellow Sea, China. Rainbow, steelhead trout and Atlantic salmon were selected as the main culture species. The aims of the present study were as follows: (a) investigate the effect of the salinity acclimation method on the growth, osmoregulation and energy budget in two forms of Oncorhynchus mykiss, rainbow and steelhead trout and (b) explore the optimal size of steelhead trout for the seawater entry. In trial I, rainbow (mean = 99.44 g) and steelhead trout (mean = 99.01 g) were reared for 40 days after undergoing salinity acclimation at three rates: an abrupt increase in salinity from 0 to 30 g/L (T30); an abrupt increase in salinity to 14 g/L, followed by a daily increase of 2 g/L (T2) or 6 g/L (T6) until reaching 30 g/L; and no salinity exposure (control treatment) (T0). In trial II, steelhead trout with body weights of approximately 100 and 400 g were cultured for 60 days with two treatments, T0 and T2, and the specific growth rate (SGR) was calculated every 10 days. In trial I, in both kinds of fish, the optimal growth performance, survival rate, osmoregulation and energy budget were observed in the T0 treatment, followed by the T2 treatment. These results indicate that O. mykiss with a body weight of approximately 100 g can adapt to sea water with a gradual transition (T2), but they are still not suitable for the seawater entry because of low growth. Based on the recorded SGRs in trial II, our formulated regression formula revealed that approximately 200 g is the optimal size of steelhead trout for the transition to sea water.     

Effects of salinity on osmoregulation,growth and survival in Asian swamp eel (Monopterus albus) (Zuiew 1793)

The Asian swamp eel Monopterus albus is normally considered a freshwater species, but can also occasionally be found in brackish water. It is an obligate air‐breather with highly reduced gills, making its osmoregulation physiology interesting because the gills normally represent the primary site of osmoregulation in teleosts. Being a popular fish for human consumption, the swamp eel is cultured extensively in freshwater ponds in the Mekong Delta of Vietnam. However, very little is known about its salinity tolerance, which is becoming topical due to the increasing salt‐water intrusions into tropical deltas. We therefore studied how increased salinity affects survival, growth, blood pressure, heart rate, blood osmolality and plasma ions. All eels survived prolonged exposure to 5 and 10 g L^?1, although plasma osmolality increased significantly at 10 g L^?1. Further elevation to 15 and 20 g L^?1 was associated with significantly elevated mortality, with a corresponding increase in plasma osmolality and ion con‐centrations. Our results show that swamp eels thrive in 0–10 g L^?1 with an optimum growth between 0 and 9 g L^?1, indicating that utilization of low saline brackish waters for aquaculture is possible.     

Effects of salinity on growth characteristics and osmoregulation of juvenile cobia,Rachycentron canadum (Linnaeus 1766), reared in potassium‐amended inland saline groundwater

The suitability of inland saline groundwater as a medium to culture juvenile cobia, Rachycentron canadum, was assessed. In the first experiment, juvenile cobia stocked in raw (unamended) saline groundwater at salinities of 5, 10, and 15 g/L exhibited complete mortality after 108, 176, and 195 hr, respectively. The second experiment evaluated the rearing of juvenile cobia (mean weight ~9.23 ± 0.12 g) in potassium (K⁺)‐amended saline groundwater (100% K⁺ fortified) and reconstituted seawater at salinities of 5, 10, and 15 g/L to assess growth and osmoregulation in distinct culture media. Following 60 days of culture, all fish survived the experimental period. Final mean bodyweight of cobia reared in K⁺‐amended saline groundwater (103.2–115.8 g) and seawater (111.2–113.8 g) of different salinities did not vary significantly (p > .05). No differences (p > .05) were observed in specific growth rate, weight gain (%), and feed conversion ratio between treatment groups. Serum osmolality increased with salinity and was significantly higher (p < .05) for fish in K⁺‐amended saline groundwater (353–361 mOsmol/Kg) than in reconstituted seawater (319–332 mOsmol/Kg), although differences were not observed between salinities by water type. Cobia stocked in saline groundwater of different salinities were osmoregulating normally, and the higher values observed may be because of variations in ionic composition and other interfering ions in saline groundwater. Trial results suggest that juvenile cobia can achieve optimal growth in K⁺‐amended saline groundwater of low and intermediate salinities.     

Short-term salinity tolerance of northern pike, Esox lucius, fry, related to temperature and size

Abstract  The short-term tolerances of northern pike, Esox lucius L., fry reared in a freshwater hatchery, to salinity were examined in the laboratory. Survival of two size groups of pike fry (mean length 21 ± 2 mm SD and 37 ± 4 mm SD) was examined over 72- to 96-h periods at 9–14 ppt salinity in combination with temperatures of 10, 14 and 18 °C. A parametric survival model found a significant correlation between survival of pike fry and temperature and salinity, respectively. L _C50 values after 72 h were between 11.2 and 12.2 ppt, being lowest at 10 °C. Pike fry did not survive more than 13 ppt. Mortality at 12 ppt was significantly faster at 18 °C than 10 or 14 °C. Moreover, mortality was higher and faster for large than for small pike fry at 12 ppt and 14 °C. These results imply that pike raised in fresh water can survive stocking into brackish waters below 11 ppt at least for a short time.     

Growth and osmoregulation in Atlantic salmon (Salmo salar ) smolts in response to different feeding frequencies and salinities

Groups of Atlantic salmon (Salmo salar) yearling smolts were reared in duplicate tanks supplied with freshwater or seawater, and subjected to different feeding frequencies, 100% (fed every day), 50% (fed every other day), 25% (fed every forth day) and 0% (starved), from 26 May to 26 July. After 8 weeks, all the groups were re‐fed in excess for 6 weeks. Fish were maintained on their respective a priori salinity treatments during the 6‐week follow‐up period. Starvation for a period of 8 weeks in freshwater resulted in a loss of hypo‐osmoregulatory ability when smolts were challenged with seawater and unfed smolts maintained in freshwater were unable to adapt to seawater in mid‐July. Ration levels influenced the growth rate and body size significantly. The overall growth rate was higher in freshwater than at corresponding rations in seawater. Partial compensatory growth was observed in the 0 and 25% groups following re‐feeding. Branchial Na⁺,K⁺‐ATPase (NKA) activity decreased rapidly in unfed smolts in freshwater and was the lowest in the starved group, whereas an initial increase was observed in those groups reared in seawater. After re‐feeding NKA activity differences decreased between the former feeding groups. Our results suggest that nutritional factors and/or energy levels are critical for the maintenance of hydro‐mineral balance of salmon smolts.     

Growth,salinity tolerance and microsatellite analysis of the F2 reciprocal hybrids of Oreochromis niloticus×Sarotherodon galilaeus at different salinities

Oreochromis niloticus (O), the sixth generation of Genetic Improvement of Farmed Tilapia, shows rapid growth but poor salt tolerance, while Sarotherodon galilaeus (S) exhibits opposite traits. To combine the traits, F₁ progeny was obtained through artificial fertilization. Fertile F₁ produced F₂ by natural spawning. The mean survival times, the median survival time (ST₅₀) or the survival rate of hybrids was greater than O. niloticus in a gradual or an acute salinity change. Plasma osmolarity, [Na⁺] and [Cl^?] of the hybrids fluctuated in 32 g L^?1 water during a 24‐h period, but eventually reached levels similar to fish in freshwater. O. niloticus♀×S. galilaeus♂ (OS F₂) or S. galilaeus♀×O. niloticus♂ (SO F₂) showed the fastest growth at 22.5 g L^?1, equal to about 78.2% or 69.7% of O. niloticus at 0 and 3.87 or 3.45 times that of S. galilaeus at their individual optimum growth. Growth in OS F₂ was 12% faster than SO F₂. Microsatellite analysis showed that F₂ had more alleles, a higher polymorphism information content and greater observed and expected heterozygosity than O. or S. Population differentiation was not detected between F₁ and F₂. All the results indicated that F₂ could be exploited for commercial production under saline conditions.     

达里湖鲫对盐度和碱度突变和渐变的耐受性

研究了达里湖鲫(Carassius auratus Linnaeus))幼鱼在盐度、碱度突变和渐变条件下的耐受性,并对在不同盐度和碱度浓度下的累计存活率、生存上限进行比较分析。研究发现,盐度突变条件下24、48、72和96 h的半致死浓度(LC50值)分别为11.795、11.089、10.809和10.534 g/L;碱度对试验鱼24、48、72和96 h的LC50分别为69.831、68.779、67.071和65.114 mmol/L。渐变条件下达里湖鲫的盐碱耐受能力均强于突变组,其碱度渐变组生存上限为109.2 mmol/L,明显高于突变组的90 mmol/L;盐度渐变组生存上限为15 g/L,与突变组差异不显著。结果表明,通过适当的驯养适应,可以显著提高达里湖鲫对碳酸盐型水质环境的适应能力和养殖的存活率。     

盐度和温度对褐菖鲉初孵仔鱼耐饥饿能力的影响

以褐菖鲉(Sebastiscus marmoratus)初孵仔鱼为研究对象,研究了3种水温(12、16、20℃)条件下,不同梯度盐度(5.0、7.5、10.0、15.0、20.0、25.0、30.0、35.0)对褐菖鲉初孵仔鱼不投饵存活指数(SAI)的影响.试验结果显示,在相同水温条件下,水体盐度对褐菖鲉初孵仔鱼的SA...     

Temperature and salinity tolerances of yellowfin sea bream, Acanthopagrus latus, at different salinity and temperature levels

Abstract Yellowfin sea bream Acanthopagrus latus (Houttuyn) (0.98 ± 0.27 g) were examined for temperature and salinity tolerances at nine different environmental regimes (0.3, 15 and 33 ppt combined with 10, 25 and 32 °C), in which the fish were subjected to gradual and sudden changes in temperature and salinity respectively. The 50% CTMax (critical thermal maximum) and the UILT (upper incipient lethal temperature) were in the range of 34.8–38.2 °C and 32.8–36.4 °C respectively. The 50% CTMin (critical thermal minimum) and the LILT (lower incipient lethal temperature) were in the ranges of 4.9–9.4 °C and 7.1–17.6 °C respectively. The 50% CSMax (critical salinity maximum) and the UILS (upper incipient lethal salinity) were in the ranges of 54–69‰ and 9–44‰, respectively. The fish at lower temperature (10 °C) and salinity of 33‰ tolerated temperature as low as 6 °C when the temperature was decreased gradually. The fish at 33 and 15‰ and lower temperature (10 °C) tolerated salinity as high as 66–67‰, whereas those at freshwater salinity level (0.3‰) and 32 °C tolerated salinity to 50‰ when salinity was increased gradually. The relationships among UILT, LILT, 50% CTMax, 50% CTMin, UILS, 50% CSMax, salinity and temperature are given.     

Larval development and salinity tolerance of Japanese flounder (Paralichthys olivaceus) from hatching to juvenile settlement

Salinity tolerance and growth of Japanese flounder Paralichthys olivaceus at different developmental stages were evaluated, including newly hatched larvae (nhl), yolk sac larvae (ysl), oil droplet larvae (odl), post oil droplet larvae (podl), premetamorphic larvae (preml) and prometamorphic larvae (proml), at 11 salinities from 5 to 55 g L^?1 for 96 h. The ontogenesis during the early life of P. olivaceus was investigated under hatchery salinity 35 g L^?1. The results showed that suitable salinities for nhl, ysl, odl, podl, preml and proml larvae were 10 to 25 g L^?1, 10 to 30 g L^?1, 20 to 30 g L^?1, 30 g L^?1, 10 to 30 g L^?1, 15 g L^?1, respectively, demonstrating an ontogenetic variation of salinity tolerance. The salinity tolerance of nhl, ysl, preml was higher than that of odl, podl and proml. The ysl and preml larvae displayed wide salinity tolerances. The present findings demonstrate that the suitable salinity for larviculture of P. olivaceus is 20–25 g L^?1 before the depletion of oil droplet; after that, higher salinity (30 g L^?1) should be ensured for the post‐oil droplet larvae; the premetamorphic larvae can be cultured at a wide salinity range (10–30 g L^?1), and the metamorphosed larvae should be reared at salinity about 15 g L^?1.     

鱼类催乳素及其在渗透压调节中的作用

溶解于水中的各种盐类,主要通过水的渗透压影响鱼类的生活,它关系到鱼类的分布、洄游、生长、发育和繁殖等很多生命活动。随着全球气候不断恶化的影响,水域盐碱化面积在我国北方地区不断扩大,许多不耐盐碱的淡水生物逐渐消失,少数喜盐或耐盐碱种类也因水域盐碱含量的升高面临考验。如何提高鱼类的耐盐碱特性,增加盐碱水域养殖鱼类品种已成为鱼类育种研究的工作重点。针对催乳素在鱼类耐盐碱生理生化过程中发挥的重要作用,本文对鱼类催乳素基因的结构,催乳素的分布、功能及其在渗透压调节中的作用等研究进展进行了概述。     

鱼类催乳素及其在渗透压调节中的作用

溶解于水中的各种盐类,主要通过水的渗透压影响鱼类的生活,它关系到鱼类的分布、洄游、生长、发育和繁殖等很多生命活动。随着全球气候不断恶化的影响,水域盐碱化面积在我国北方地区不断扩大,许多不耐盐碱的淡水生物逐渐消失,少数喜盐或耐盐碱种类也因水域盐碱含量的升高面临考验。如何提高鱼类的耐盐碱特性,增加盐碱水域养殖鱼类品种已成为鱼类育种研究的工作重点。针对催乳素在鱼类耐盐碱生理生化过程中发挥的重要作用,本文对鱼类催乳素基因的结构,催乳素的分布、功能及其在渗透压调节中的作用等研究进展进行了概述。     

三种鳅科鱼对NaCl盐度和NaHCO3碱度的耐受能力

以鳅科的黑龙江泥鳅(Misgurnus mohoity Dybowsky)、大鳞副泥鳅(Paramisgurnus dabryanus Sauvage)、达里湖高原鳅(Triplophysa dalaica)为实验材料,采用单因子静态急性毒性实验法和均匀正交设计法对其盐碱耐受能力进行研究。实验结果表明,黑龙江泥鳅、大鳞副泥鳅、达里湖高原鳅的24 h和96 h的氯化钠(Na Cl)盐度半致死浓度(LC50)分别为15.64 g/L和13.58 g/L、15.43 g/L和14.18 g/L、14.00 g/L和11.57 g/L,安全浓度(SC)分别为4.12 g/L、4.03 g/L、3.74 g/L,盐度耐受能力顺序为:黑龙江泥鳅大鳞副泥鳅达里湖高原鳅。黑龙江泥鳅、大鳞副泥鳅、达里湖高原鳅的24 h和96 h碳酸氢钠(NaHCO_3)碱度半致死浓度(LC50)分别为117.1 mmol/L和72.62 mmol/L、128.4 mmol/L和88.83 mmol/L、155.2 mmol/L和120.0 mmol/L,安全浓度分别为18.77 mmol/L、23.66 mmol/L、36.30 mmol/L,碱度耐受能力顺序为:达里湖高原鳅大鳞副泥鳅黑龙江泥鳅。盐碱交互作用对黑龙江泥鳅、大鳞副泥鳅均表现为协同作用,协同系数0~48 h依次增高,以后逐渐减小;而对达里湖高原鳅在0~48 h内表现为协同作用,在48~96 h时表现为拮抗作用,拮抗系数随着暴露时间的延长而增大。对比分析可知,3种鳅科鱼的盐碱耐受能力比大多数淡水鱼高,可作为盐碱水域的增养殖鱼类;而达里湖高原鳅在耐碱方面表现更突出,可以作为高碳酸盐型盐碱水的增养殖鱼类。     

水体盐度对雌性三疣梭子蟹生长、卵巢发育、渗透压调节、代谢和抗氧化能力的影响

为研究长期盐度适应对雌性三疣梭子蟹生长、卵巢发育、渗透压调节、代谢和抗氧化能力的影响,本实验设置了不同盐度(10、15、20和25)的水体,对生殖蜕壳后三疣梭子蟹雌体进行60 d的盐度适应实验。结果显示:(1)雌蟹的成活率、增重率、特定生长率和性腺指数随水体盐度的升高而显著上升。(2)血清渗透压、Na~+、Cl~–、Ca~(2+)、Mg~(2+)、大部分游离氨基酸和总游离氨基酸含量及后鳃Na~+/K~+-ATP酶活性均随水体盐度的升高而显著上升。(3)血清中葡萄糖和肝胰腺乳酸含量随水体盐度的升高而显著降低,而血清中的尿素氮、尿酸及肝胰腺中的尿酸含量均随水体盐度的升高而显著上升;肝胰腺中的甘油三酯、总胆固醇和尿素氮含量均在20和25盐度组较高。(4)10盐度组血清和肝胰腺中的总超氧化物歧化酶活性显著低于其他组,而血清中的总抗氧化能力、谷胱甘肽过氧化物酶、γ-谷氨酰转肽酶、血蓝蛋白和肝胰腺中的谷胱甘肽过氧化物酶、丙二醛水平均在10盐度组最高。研究表明,水体盐度升高可促进三疣梭子蟹生长和卵巢发育;在20和25盐度条件下,雌蟹机体的代谢水平和氧化胁迫较低。     

Effect of temperature and salinity on low thermal tolerance of Penaeus semisulcatus (Decapoda: Penaeidae)

Critical thermal minima (CTmin) and lower incipient lethal temperature (LILT) were determined for Penaeus semisulcatus juveniles at combinations of four acclimation temperatures (18, 22, 26 and 30 °C) and four salinity levels (20, 25, 30 and 35 ppt). While the CTmin and LILT of shrimps were not affected significantly by salinity ( P >0.05), a direct relationship was determined between the thermal minima values (CTmin, LILT) and the acclimation temperature ( P <0.05). The acclimation response ratio for the juveniles of P. semisulcatus had an interval of 0.18–0.32 in the current study.     

三疣梭子蟹低盐耐受性相关甲基化标记的开发及验证

为开发三疣梭子蟹低盐耐受性相关甲基化标记,采用甲基化敏感性高分辨率熔解曲线法(methylation sensitive high resolution melting curve, MS-HRM)进行了三疣梭子蟹低盐耐受性相关甲基化位点的筛选和应用。结果显示,从三疣梭子蟹转录组数据库中共开发了8个甲基化标记,其中6个标记与低盐度耐受性显著相关,在低盐度条件下表现出显著的去甲基化或甲基化,这些标记分别位于V-ATP酶(V-type proton ATPase)、CLC型氯离子通道、琥珀酸脱氢酶、NAD(P)转氢酶(NAD(P)、磷酸乙醇酸性磷酸酶、NADH还原酶基因,为三疣梭子蟹耐低盐新品种的分子标记辅助选育提供候选工具。研究表明,“宁象1号”耐低盐能力显著高于野生群体,且选育群体中位点Pt-M1、Pt-M2的去甲基化率达到100%,可能有利于低盐条件下保持体内Na⁺和Cl^-的平衡。