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1.
Overwintering is an important part of the conservation of Scylla paramamosain, and salinity has an important effect on the conservation of S. paramamosain during overwintering. Three salinities (4‰, 12‰ and 25‰) were selected as the overwintering salinities to reveal the effects of different salinities on the relevant important ions in osmotic pressure regulation, plasma cortisol, digestive enzymes, immune enzymes and amino acids of S. paramamosain during indoor overwintering. Results indicated that after overwintering, Cl‐, Na+ and the osmotic pressure of serum have the highest salinity at 25‰, and the lowest salinity at 4‰. Na+/K+‐ATPase activity and cortisol were found to increase with decreasing salinity. The activity of digestive and immune enzymes was highest at 25‰, and was the lowest at 4‰. The amount of total amino acids (TAA), umami amino acids (UAA) and essential amino acids (EAA) in 25‰ were significantly higher than in 4‰ and 12‰. After overwintering, the essential amino acid index (EAAI) in the salinity range of 12–25‰ was 54.04–59.00, compared to 48.56–54.04 in the salinity range of 4–12‰. As a result, S. paramamosain at 25‰ had higher digestion and immunity than at 4‰ and 12‰, due to requiring more energy for osmotic pressure adjustment. In addition, S. paramamosain at 25‰ had the best meat quality. The results of this study are helpful for aquaculture production for indoor overwintering of S. paramamosain.  相似文献   

2.
This study aimed to investigate the effects of adding crude extracts of the extracellular protein (Ex‐Pro) and intracellular polysaccharides (In‐Poly) of Vibrio alginolyticus to diets, at a dosage of 10 g/kg, on the growth, energy metabolism and WSSV (White Spot Syndrome Virus) resistance of Litopenaeus vannamei (initial weight, 0.88 ± 0.04 g/shrimp). Growth and survival rate were not significantly affected by the crude extracts (p > 0.05). Shrimp fed Ex‐Pro crude extracts showed higher succinate dehydrogenase (SDH) activity in the hepatopancreas and muscle but lower lactate dehydrogenase (LDH) activity in the muscle (p < 0.05). The activities of hexokinase (HK), pyruvate kinase (PK), LDH and SDH in the hepatopancreas and the activity of SDH in the muscle were significantly increased by feeding In‐Poly crude extracts (p < 0.05). In contrast, the content of fatty acid synthase (FAS) in the muscle was significantly reduced by the crude extracts (p < 0.05). The contents of glucose and triglyceride and the activity of the electron transport system in the hepatopancreas were significantly increased by the crude extracts (p < 0.05), and the WSSV resistance of the shrimp was increased. These results indicated that the Ex‐Pro and In‐Poly crude extracts of V. alginolyticus could affect energy metabolism, and there was a correlation between WSSV resistance and energy metabolism in L. vannamei.  相似文献   

3.
Juvenile Litopenaeus vannamei farmed at 3.0 psu were fed five diets containing glucose, sucrose, wheat starch, corn starch or potato starch as the carbohydrate (CBH) source. Shrimp were fed for 50 days to explore the effect of dietary CBH source on growth, body composition and ammonia tolerance. The specific growth rate of body length of shrimp fed glucose was the highest and significantly higher than those fed potato starch. The survival rate of shrimp fed glucose was 89.44%, and it was the highest and significantly higher than those fed wheat starch. Whole shrimp body crude protein and lipid of the corn starch group were 140.2 g kg?1 and 10.1 g kg?1 respectively. And they were significantly higher than those fed wheat starch. Shrimp fed potato starch had higher hepatopancreas and muscle glycogen. Shrimp fed sucrose had higher glucose‐6‐phosphate dehydrogenase and lower pyruvate kinase activities (P < 0.05). Besides, shrimp fed starch produced more B cells in hepatopancreas tubules than those fed glucose or sucrose. Shrimp fed different sources of CBH differed in the number of R cells. After 96‐h of ammonia nitrogen challenge, the survival rate of the treatments from high to low in turn was glucose, wheat starch, corn starch, sucrose and potato starch, and no significant differences were observed among all treatments. Based on shrimp growth and the economic problems of practical production, we recommend wheat starch as CBH source in practical diets for L. vannamei farmed at low salinities.  相似文献   

4.
This study evaluated the influence of dietary supplementation with freeze‐dried powder of Ampithoe sp. (FDPA) on the growth, energy metabolism, and resistance to ammonia‐nitrogen stress in Litopenaeus vannamei. There were four treatment groups: a 0% group (no FDPA addition), a 33% group, a 66% group (33% and 66% of the shrimp diet, respectively, replaced with FDPA), and a 100% group (only FDPA). The results of this study suggested a positive effect of FDPA supplementation on shrimp survival: the supplemented groups had significantly higher survival than the 0% group (p < 0.05). The body length, body weight, and specific growth rate (SGR) of the 33% group were higher than those of the other groups and were significantly higher than that of the 100% group (p < 0.05). FDPA feeding had a negative effect on carbohydrate metabolism pathways and energy consumption due to decreases in pyruvate kinase (PK), phosphofructokinase (PFK), succinate dehydrogenase (SDH), lactic dehydrogenase (LDH), and respiratory electron transport system (ETS) activity in shrimp fed FDPA during the culture period. The shrimp in the 33% group exhibited good resistance to ammonia‐nitrogen stress. Additionally, the glycolysis pathway and energy consumption of shrimp in the 33% group were enhanced during the ammonia‐nitrogen stress period. Consequently, it was inferred that FDPA supplementation could improve the resistance of shrimp to ammonia‐nitrogen stress (in the 33% group), which might be related to the effects of the supplement on energy metabolism pathways, particularly in terms of enhancing glycolysis to provide sufficient energy for the stress response.  相似文献   

5.
盐度对三疣梭子蟹成熟前后呼吸代谢的影响   总被引：2，自引：2，他引：0  
路允良  王芳  高勤峰  董双林 《水产学报》2012,36(9):1392-1399
为了探讨三疣梭子蟹对不同盐度水平的生理响应以及成熟前后的生理变化,实验采用水化学和酶学方法,研究了盐度(15、20、25、30和35)对成熟前后三疣梭子蟹耗氧率、排氨率、氧氮比(O∶N)以及己糖激酶(HK)、丙酮酸激酶(PK)、琥珀酸脱氢酶(SDH)和乳酸脱氢酶(LDH)4种呼吸代谢酶活力的影响。结果发现:1.盐度与规格的交互作用对三疣梭子蟹呼吸代谢无显著影响(P>0.05);2.盐度对三疣梭子蟹耗氧率的影响不显著(P>0.05),但显著影响其排氨率(P<0.05);成熟前后的三疣梭子蟹耗氧率和排氨率差异显著(P<0.05);3.盐度对三疣梭子蟹O∶N未产生显著影响(P>0.05),三疣梭子蟹成熟前O∶N显著高于成熟后(P<0.05);4.除LDH外,盐度对三疣梭子蟹呼吸代谢酶活力影响不显著(P>0.05);除鳃中SDH和LDH外,三疣梭子蟹呼吸代谢酶活力随生长发育发生显著变化(P<0.05)。研究表明,规格对三疣梭子蟹呼吸代谢的影响高于盐度,长时间盐度驯化可能减弱甚至消除三疣梭子蟹在不同盐度水平下代谢的差异。  相似文献   

6.
A 6‐week study was conducted to determine the effects of different lipid sources in pelleted diets on juvenile mud crab Scylla paramamosain. Five isonitrogenous and isolipidic diets containing 8% level of fish oil (FO), lard (LD), safflower oil (SO), perilla seed oil (PO) or mixture oil (MO; VFO:VSO:VPO = 1:1:1), and a live food of marine bivalve Potamocorbula rubromuscula as the control diet (CF), were fed to groups of 25 juvenile crabs (average initial weight 7.4 g, carapace width 3.5 cm) in triplicate. The results showed that crabs fed MO had the highest survival (P < 0.05). The moisture content was significantly higher in crabs fed LD, SO and PO (P < 0.05). Crabs fed SO exhibited the lowest crude protein and lipid (P < 0.05). Ash contents were obviously lower in LD group (P < 0.05). Highest total lipid in the hepatopancreas and muscle was in LD and FO group respectively. Glucose, total cholesterol and low‐density lipoprotein were higher while high‐density lipoprotein was lower (P < 0.05) in LD group. Tissue fatty acid compositions were consistent with those in diets. FO and MO diets had the same depression effect like CF on fatty acid synthase activity and mRNA expression in the hepatopancreas. The results of this study indicated that FO and mixed oil are suitable for preparation of pelleted diets with better effects for juvenile S. paramamosain compared with live food, and the ratio of n‐6/n‐3 fatty acids in pelleted diets must be <1.  相似文献   

7.
In order to reveal the influence of overwintering behaviour on the flavour of Scylla paramamosain, this study selected crabs of before and after overwintering in SM (Sanmen County, Zhejiang Province), HP (Hepu County, Guangxi Province) and WN (Wanning city, Hainan Province). The contents of flavouring‐related substances in hepatopancreas, muscles and gonads were determined by high‐performance liquid chromatography (HPLC); taste activity value (TAV) and equivalent umami concentration (EUC) were calculated. The results showed that sweetish amino acids were mainly accumulated in muscles, umami amino acids were mainly accumulated in hepatopancreas, free nucleotides were mainly accumulated in gonads, and the EUC value in gonads was the highest. After overwintering, the content of sweetish, umami amino acids and free nucleotides in muscle and hepatopancreas decreased significantly, while the content of flavour‐tasting amino acids in gonads did not change significantly, but the content of umami nucleotides increased significantly. Therefore, overwintering behaviour decreased the flavour of muscle and hepatopancreas, slightly enhanced gonad and the overall flavour of S. paramamosain before overwintering was better than that after overwintering.  相似文献   

8.
The sea cucumber Apostichopus japonicus is an economic species mainly distributed along the coast of northern China, south‐eastern Russia, Japan, Republic of Korea and Democratic People's Republic of Korea. Aquaculture industry of A. japonicus has been facing severe challenge of high temperature. In this study, we studied the mRNA expression profiles of eight key metabolic enzymes involved in carbohydrate and amino acids metabolism in A. japonicus under heat stress. The expression of hexokinase, pyruvate kinase and malate dehydrogenase showed downregulated response to heat stress, while the expression of glutamate dehydrogenase, alanine transaminase and branched‐chain aminotransferase showed upregulated response. In addition, the expression of lactate dehydrogenase and glutamate synthase showed no significant difference. We also applied 1H NMR‐based metabolomics to investigate metabolic changes in the intestine tissue of A. japonicus under heat stress, the results of which revealed nine increased and 10 decreased metabolites in the heat stress group. These response genes and metabolites have potential to become markers for identifying severity of heat stress. More importantly, our findings suggest significant links between gene expression and metabolites changing, highlighting regulation networks of carbohydrate and amino acid metabolism in heat‐stressed A. japonicus.  相似文献   

9.
Estrogen administration in C. punctatus increases RNA: protein and RNA: DNA ratios and depletes glycogen in the liver. Increase in glucose-6-phosphatase activity accounts for glycogen depletion whereas high activity of pyruvate kinase suggests stimulation of the glycolytic pathway at the pyruvate step to generate ATP and to provide carbon skeleton for the vitellogenin molecule. Five-fold increase in the activity of NADP+-dependant malate dehydrogenase generates NADPH possibly for fatty acid synthesis. Additional energy requirement (NADPH) is met by stimulation of hexose monophosphate pathway as well as NADP+-dependant isocitrate dehydrogenase. Increase in the activity of NADPH-cytochrome c reductase in microsomal fraction suggests stimulation of electron transport chain. Increase in the activity of glutamate pyruvate transaminase can be directly related to the synthesis to specific amino acids needed for the formation of vitellogenin whereas reduction in glutamate oxaloacetate suggests extra hepatic source of amino acids. Reduction in the activity of glutamate dehydrogenase may be due to catabolism.  相似文献   

10.
Nitrite is usually found in aquatic environments where nitrification process occurs. This ion can cause several injuries to aquatic species, particularly fish. Nitrite reacts with haemoglobin yielding the non‐functional methaemoglobin, which leads to many physiological consequences such as functional anaemia and supposed hypoxia. Metabolism of the freshwater teleost matrinxã, Brycon amazonicus, exposed to environmental 0.6 mg L?1 of nitrite N‐NO2? for 96 h was studied, and the fermentative/oxidative preference was gauged. Concentrations of glycogen, glucose, lactate, pyruvate and ammonia, plus the activities of lactate, glutamate and malate dehydrogenase were assayed. The exposure resulted in a metabolic profile that allowed inferring the continuity of oxidative metabolism. Catabolism of amino acids prevailed or was apparently exacerbated by inferred branchial injury and consequent impairment of nitrogen excretion. Moreover, the studied enzymes glutamate dehydrogenase, lactate dehydrogenase and malate dehydrogenase from brain and heart were little affected by nitrite. The expected fermentative metabolism due to the high methaemoglobin formation was not observed.  相似文献   

11.
Juvenile matrinxã, Brycon cephalus, were submitted to sustained swimming for 72 days at 1.0 body length s?1. Exercised fish (EF) grew more than non‐EF and their feed conversion ratio (FCR) improved; haematological responses demonstrated a decrease in haemoglobin and mean cell haemoglobin contents and increase in the mean cell volume. In the plasma, sodium, ammonia and amino acid concentrations increased; plasma triglycerides decreased while free fatty acids increased. Liver glucose, free amino acids, ammonia, the rate protein per fish weight and total lipid content increased, while the glycogen per fish ratio declined. Glutamate dehydrogenase (GDH) activity increased while pyruvate kinase (PK) and lactate dehydrogenase (LDH) decreased. White muscle glucose, lactate, the glycogen per fish‐weight ratio and total lipid content exhibited a decrease in their values; ammonia, free amino acids and the protein per fish‐weight ratio increased. GDH and PK decreased their activities. In the red muscle glycogen store, the glycogen per fish‐weight ratio and glucose were reduced. Juvenile matrinxãs, under sustained swimming, were physiologically and biochemically adapted to exercise as indicated by improved blood flow, transport and oxygen uptake, FCR, amino acid and protein incorporation and growth. Continuous exercise is a good practice for B. cephalus cultivation.  相似文献   

12.
The physiological responses to different environmental salinities were assessed in juveniles of large yellow croaker Pseudosciaena crocea. This species shows a good capacity to adapt to comparatively low environmental salinities by evaluating some physiological responses, i.e. superoxide dismutase (SOD), acid phosphatase (ACP), alkaline phosphatase (AKP) and lysozyme (LZM) in the liver, spleen, gill and kidney respectively. Growth and survival at salinity 5‰, 10‰ and 25‰ were better than those at salinity 15‰ and 20‰. No significant differences in ACP, AKP, SOD and LZM in the liver were observed among different salinity treatments; SOD, AKP and LZM in the spleen among different treatments only showed significant differences at the beginning or the 2nd week; in the gill, no significant difference of AKP and LZM were observed during the whole experiment, SOD among different treatments showed significant difference at the beginning and the 8th week, and ACP only showed significant difference at the end of the experiment; in the kidney, significant differences in ACP, AKP and SOD among different salinities were merely observed at the end of experiment, and LZM showed significant difference among different treatments at the 2nd week. Overall, some slight stress responses were observed, but few significant differences were observed between low salinity and normal salinity, especially the growth and physiological functions were not influenced by low salinity, i.e. 5‰ and 10‰. We conclude that juvenile large yellow croaker is tolerant to low salinity and shows a potential for low salinity culture.  相似文献   

13.
Despite the importance of certain highly unsaturated fatty acids in osmotic regulation, few studies have been addressed to determine the essential fatty acid requirements for a given species cultured under different salinities. As Galaxias maculatus is a diadromic species, the present study aimed to determine the effect of salinity on the optimum dietary EPA/docosahexaenoic (DHA) ratio for survival and growth during the larval stages. Larvae were fed for 20 days with rotifers containing two different EPA/DHA ratios (low: 0.64 and high: 2.18) at three different salinities (0, 10 and 15 g L?1). The results of this study showed a marked effect of water salinity on larval dietary lipid utilization in G. maculatus larvae. These results suggested that G. maculatus larvae reared at higher salinities may have a higher dietary requirement for DHA, whereas larvae reared at 0‰ showed higher requirements for EPA. The overall results of the present study indicate that even small changes in salinity can determine the optimum dietary EPA/DHA ratio and the quantitative essential fatty requirements of fish. This may have important repercussions and affect the rearing performance of G. maculatus cultured under different salinities.  相似文献   

14.
Salinity has been proven to have a significant effect on the growth and survival of anadromous fish species; however, there is a paucity of information regarding its effect on euryhaline marine species. Experiments were conducted to examine the effect of hyposalinity on the osmoregulation and growth of juvenile spotted grunter, Pomadasys commersonnii (Lacépède). Although the spotted grunter is considered to be a strong osmoregulator, growth performance and survival was compromised below isosmotic concentrations. The growth rate, condition and food conversion of fish in low salinity (5‰) were lower than in either isosmotic (12‰) or hyperosmotic (25‰ and 35‰) conditions. Mortality was also significantly higher at 5‰. From these results, it is concluded that P. commersonnii can be successfully cultured in salinities ranging from 12‰ to full-strength sea water (35‰).  相似文献   

15.
We examined the effects of dietary carbohydrate sources on growth performance, digestive ability, immunity and glycometabolic enzyme activity of Rhynchocypris lagowskii Dybowski. The fish were fed with glucose, sucrose, dextrin and corn starch for 8 weeks. Final body weight, weight gain rate, specific growth rate, feed efficiency ratio and protein efficiency ratio were positively related to the complexity of carbohydrates in diet as were the levels of total antioxidant capacity, complement 3, protease, glutathione peroxidase, amylase, alkaline phosphatase, lysozyme, catalase, superoxide dismutase, fructose‐1,6‐bisphosphatase, hexokinase and pyruvate kinase. Malondialdehyde content, hepatic glycogen, glucose‐6‐phosphate dehydrogenase, hepatosomatic index, viscerosomatic index and crude lipid content were negatively related to the complexity of carbohydrates in diet. Therefore, Rhynchocypris lagowskii Dybowski fed with corn starch or dextrin showed positive effects in terms of growth, digestion and absorption, glycolysis, gluconeogenesis, antioxidant capacity and immunity than those fed with glucose or sucrose.  相似文献   

16.
The effect of ambient salinity on the haemolymph variables of Fenneropenaeus indicus and its susceptibility to Vibrio harveyi infection under salinity stress has been studied. Adult shrimps were acclimated to 5‰ (hypo osmotic), 25‰ (iso osmotic) and 35‰ (hyper osmotic) salinity levels and the animals were injected with a mid logarithmic culture of V. harveyi at sub lethal level and haemolymph parameters were analysed. Haemolymph proteins, intracellular superoxide anion production, phenoloxidase (PO), alkaline phosphatase (ALP) and acid phosphatase (ACP) activity were found to be at elevated level both at 5‰ and 35‰ post challenge. The haematological responses showed a progressive increase (P < 0.05) up to post challenge day 5 (PCD 5) followed by a considerable decline at all salinities with the lowest being at 35‰. The alterations in the variables were higher in shrimps held at 5‰. However, the V. harveyi infection was severe in animals held at 35‰. The reduction in the parameters could be correlated with the decrease in survival rate of shrimps at 35‰ with a concurrent increase in V. harveyi at this salinity. Multiple regression analysis revealed that ACP (P < 0.001), haemocyte protein HCP (P < 0.001) and PO (P < 0.05) could explain 91% variability in the shrimp survival. These parameters may be used as effective shrimp health indicators. It is evident from the study that ambient salinity alters the haemolymph variables, modulates the virulence in V. harveyi and makes the shrimps more vulnerable to infection at higher salinity. The virulence of V. harveyi is increased at 35‰ salinity as being evidenced from the high mortality at this salinity. The study emphasizes the importance of salinity as an important environmental factor both in terms of host susceptibility and virulence of the pathogen.  相似文献   

17.
A study was performed to examine the effects of salinity on water quality, fish performance, carcass composition and haemato‐biochemical parameters in juvenile meagre, Argyrosomus regius. Fish (5.0 g) were stocked in fibreglass tanks at four salinity levels: 8‰, 16‰, 24‰ and 32‰, and fed a pelleted diet (47/17 protein/lipid) for 56 days. Results indicated that the growth, feed utilization, carcass composition and haemato‐biochemical parameters of meagre gradually improved with the increase in salinity up to 24‰ and then significantly (p ≤ .05) decreased at 32‰. The survival per cent showed a significant decrease when A. regius exposed to 8‰ salinity. An improvement with 32%, 47% and 34.1% of FCR, protein productive value and energy utilization was detected at 24‰ compared with 8‰ salinity respectively. The highest content of protein and the lowest of lipids were recorded in fish carcass at 24‰ compared with the opposite trend at 8‰ salinity. The 24‰ salinity treatment exhibited the highest value of haemoglobin (4.9 g/dl) and the lowest ratio (0.73) of albumin/globulin. The serum total protein, albumin and globulin were significantly higher at 24‰ and 32‰ salinity than those at 8‰ and 16‰ salinity groups. These findings indicate that 24‰ salinity level might be the best for meagre.  相似文献   

18.
The composition of seminal plasma and metabolism of sperm of the cyprinid fishAlburnus alburnus were investigated. Statistically significant correlations were found between motility parameters and seminal fluid osmolality, pH, Na+, K+ and protein levels (negative correlations: % immotile spermatozoa-Na+, K+; positive correlations: % motile spermatozoa-osmolality, pH, Na+, K+, protein; % linear motile spermatozoa-pH protein; swimming velocity of spermatozoa-pH, Na+, protein). Spermatozoan motility and ATP metabolism and glycolysis were correlated as indicated by measurement of ATPase, pyruvate kinase, adenylate kinase and lactate dehydrogenase activity. The physiological meanings of these correlations and their possible significance for quality control of semen are discussed.Abbreviations used ACP acid phosphatase - ADP adenosine diphosphate - AK adenylate kinase - ALP alkaline phosphatase - ASPAT aspartate aminotransferase - ATP adenosine triphosphate - ATPase magnesium dependent adenosine triphosphatase - CRPO creatine phosphate - -GLU \-D-glucuronidase - ICDH isocitrate dehydrogenase - LDH lactate dehydrogenase - PK pyruvate kinase  相似文献   

19.
To study the effects of different flow velocities on growth, metabolism and nitrogen (N) and phosphorus (P) budget of Haliotis discus hannai Ino in a recirculating aquaculture system, abalones (shell length: 45.71 ± 3.09 mm, body weight: 8.62 ± 0.75 g) were cultured at three different flow velocities with four replicates each: high (400 L/hr), medium (300 L/hr) and low (200 L/hr). At the end of the 70 days experiment, the survival rate, food intake and P utilization rate of abalones in the 200 L/hr group were significantly lower than those in any other group (p < .05), whereas the total ammonia nitrogen and nitrite nitrogen concentrations in the water were significantly higher than those in any other group (p < .05). The body weight specific growth rate, food conversion efficiency, abalone‐harvested N and P outputs and N utilization rate were ranked as follows: 300 > 400 > 200 L/hr (p < .05). In the 300 L/hr group, the activities of hexokinase, pyruvate kinase and lactate dehydrogenase were significantly lower than those in the 400 L/hr group, whereas the activity of succinate dehydrogenase was significantly higher than that in the other two groups (p < .05). Aerobic metabolism was the main source of energy acquisition for abalones in the 300 L/hr group. In the 400 L/hr group, the expression levels of manganese superoxide dismutase and thioredoxin peroxidase significantly increased from Day 35 to Day 70, but they still were significantly lower than the values in the 200 L/hr group (p < .05). In the 200 L/hr group, the expression levels of catalase and heat shock protein 70 were significantly higher than those in any other group, and they significantly increased from Day 35 to Day 70 (p < .05). These results indicate that maintaining flow velocity at 300 L/hr will minimize oxidative damage due to deterioration of water quality, reduce the energy consumption required for organisms to resist the impact of water flow, improve the N and P utilization rates of the recirculating aquaculture system, and reduce the cost of culturing abalones.  相似文献   

20.
The giant freshwater prawn, Macrobrachium rosenbergii, is a species with a high commercial value in aquaculture. Two experiments were performed to determine the effects of salinities on the osmoregulation, growth and molting cycles of M. rosenbergii during growout. The first experiment was designed to determine whether these animals are capable of adapting to the changes in salinity seen in salinity intrusions in tropical deltas, with an incremental increase in salinity of 3‰ per day from 0‰ to 30‰ Haemolymph osmolality was rapidly regulated up to salinities of 15‰ , whereas animals conformed at higher salinities. The second experiment determined the growth, moulting cycle, osmolality, muscle water content and mortality during a 4‐month experiment at 0‰, 15‰ or 25‰ salinity. The weight gains in 0‰ and 15‰ were not significantly different and were comparable to the growth rates achieved in production farms with body mass increases of 2.6 and 2.3‐fold their initial body mass, respectively, after 4 months. The 25‰ group suffered from low growth, high mortality and a significantly lower moulting frequency. These data show that this species can be reared in brackish water up to 15‰, allowing for farming in the large areas impacted by salt water intrusions in tropical deltas.  相似文献   

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