The spotted scat (Scatophagus argus) is a euryhaline marine fish with the capability to withstand different salinity levels and can tolerate abrupt transfer from salt water (SW) to fresh water (FW) or vice versa. Differentially expressed genes were identified by constructing suppression subtractive hybridization (SSH) cDNA libraries to explore branchial osmoregulatory mechanisms affected by salinity challenge. After trimming and blasting, 105 uniquely expressed sequence tags were identified. Among them, 24 candidate genes involved in the stress response, metabolism, and the respiratory chain were chosen for further validation by real-time polymerase chain reaction. More than two-fold expression differences were observed in ADP-ribosylation factor 1 (arf1), cyclic AMP-responsive element-binding protein 3-like 4 (creb3l4), EVI5-like protein (evi5l), protocadherin fat 2 (fat2), transferrin receptor protein 2 (tfr2), C-X-C chemokine receptor type 4 (cxcr4), aquaporin-3 (aqp3), sodium/potassium-transporting ATPase subunit beta-233 (nka β233), serum and glucocorticoid-regulated kinase 1 (sgk1), and ras GTPase-activating-like protein IQGAP1 (iqgap1). Among these genes, aqp and nka are important osmoregulatory factors. AQP3 protein was observed being localized to the membranes of mitochondrion-rich cells (MRCs) and pillar cells of the gill of S. argus, and NKA β233 subunit isoform was only found in MRC membranes by immunostaining. Significant differences in aqp3 and nka β233 expression occurred within 24h after being transferring into the freshwater, and nka β233 expression level continued to highly upregulated 2 and 7days post-transfer (dpt). These results suggest that branchial aqp3 and nka β233 play important roles in response to hypo-osmotic stress in S. argus.

Objective] To reveal the effects of surface proteins and lipids on hydrolysis dynamics of rice starch.[Method] The surface pro-teins and lipids were removed from starch granules using the sodium dodecyl sulfate.The starch was hydrolyzed byα-amylase and amylogluco-sidase.The starch hydrolysis was measured.[ Result] The surface proteins and lipids decreased the hydrolysis rate.The effect was not con-spicuous in waxy starch, but was conspicuous in starch with high amylose content.[ Conclusion] The surface proteins and lipids have certain impacts on the hydrolysis of starch.

The morphological and histological development of digestive system was observed in larval Pacific cod Gadus macrocephalus from 1 to 50 days post hatching ( DPH) under a light microscope. No differentiation in the di-gestive system was found at hatching, the mouth and anus were not opened, and liver and pancreas were appeared. The mouth gape was formed at 3 DPH and the intestine began to be differentiated. At 6 DPH, the digestive tract was consisted of buccopharynx, oesophagus, stomach anlage, intestine and rectum, with movable premaxilla and maxilla, with initial feeding capacity. The yolk sac was depleted completely at 12 DPH, and the intestine folds and mucus cells increased progressively in number, with almost complete digestive system and onset of exogenous nutri-tion. The intestine was spiral in shape, and the digestive organs and associated glands became further development steadily, similar to that in adult Pacific cod at 47 DPH. The findings provide a theoretical basis for the scientific management and nutrition for Pacific cod larva rearing.

In this study, we compared the physicochemical qualities and the muscle textural characteristic including the water holding capacity, the collagen content, the muscle fiber diameter and other textural characteristics, between the wild, pond-cultured, and factory-culturedParalichthys olivaceus. Our observations were: (1) The drip loss rate of the muscles on the eye side or blind side followed the order wild>pond>factory (P<0.01). The water loss of the fac-tory-cultured group was higher than that of the wild and the pond-cultured groups (P<0.01). There was no significant difference between the wild group and the pond-cultured group (P>0.05). (2) There were no differences in the collagen content or the muscle fiber diameter of the muscles on the eye side or the blind side between the three groups (P>0.05). (3) The principal component analysis suggested that adhesiveness and gumminess were the main indicators of the tex-tural characteristics of theP. olivaceus muscles. The factory-culturedP. olivaceus showed higher water-holding capacity, while the pond-cultured P. olivaceus and the wildP. olivaceus were similar regarding the physicochemical qualities and the textural characteristics of the muscles. The results implied that the wildP. olivaceus might not have remarkable ad-vantage in the physicochemical qualities.

By interacting with Na(+), K(+)-ATPase (NKA), the FXYD domain-containing ion transport regulator (FXYD) is involved in teleost osmoregulation, but knowledge of FXYD in marine fish is limited. In the present study, fxyd11 and fxyd12 were identified from the spotted scat (Scatophagus argus), and the two members of the FXYD protein family were expressed in a tissue-specific manner. Fxyd11 mRNA was predominantly expressed in gills, whereas fxyd12 mRNA was mainly distributed in kidneys and intestines. Acute hyposaline stress altered the activity of NKA and the expression of fxyd11 and fxyd12 in gills, kidneys, and intestines. Branchial fxyd11 mRNA expression remained at a low level during freshwater acclimation, whereas NKA activity increased, showing a negative correlation that differed from previous reports. Similarly, renal expression of fxyd11 and fxyd12 mRNA was negatively correlated with NKA activity. Unlike in gills and kidneys, intestinal NKA activity and mRNA expression of fxyd11 and fxyd12 were comparably suppressed. Taken together, the salinity-dependent expression of fxyd11 and fxyd12, and correlation with NKA activity suggested that both fxyd11 and fxyd12 were involved in the response to acute hyposaline challenge in the spotted scat.

The effects of seawater salinity, pH and diet on growth and development of the planktonic larvae in clam Modiolus modiolus were investigated in order to explore the optimum culture conditions. It was found that growth and development of the planktonic larvae were significantly affected by the 3 ecological factors ( P<0 . 05 ) . The planktonic larvae had normal growth and development at a salinity of 25-30 , with the optimal salinity of 30 , show-ing stronger tolerance to high salinity than to low salinity. The suitable pH range for growth was changed from 6 to 9, and the best growth and maximal survival was observed in the larvae at pH 8. In diets experiment, both the best growth and higher survival rate were found in the larvae fed the alga mixture of Isochrysis zhanjiangensis, Nitzschia closterium and Chaetoceros muelleri Lemmerman. However, the worst growth and lower survival were observed in the planktonic larvae fed single Chaetoceros muelleri Lemmerman or mixture of Chaetoceros muelleri Lemmerman with Nitzschia closterium, indicating that Isochrysis zhanjiangensis meets the nutritional requirement of the planktonic lar-vae for early growth and development. There were no significant differences in growth and survival in larvae fed Iso-chrysis zhanjiangensis and Nitzschia closterium only and the mixed microalgae containing Isochrysis zhanjiangensis (P>0. 05).

The spotted scat, Scatophagus argus, has become a popular commercial fish in recent years. However, spotted scat fingerlings originate mainly from wild resources due to difficulties in the artificial propagation of this species. Thus, an understanding of its population genetic structure is necessary for its conservation management and commerical development. A valuable technique for conservation and evolutionary studies is the examination of single nucleotide polymorphisms (SNPs) using next-generation sequencing. In the present study, novel SNPs were discovered using high-throughput 454 pyrosequencing in the spotted scat (S. argus). The SNPs were detected in 4,825 contigs after de novo assembly. Among them, 33 SNPs were validated with high-resolution melting analysis using 36 individuals originating from 2 wild populations (Dinghai, Zhejiang: latitude 30°0′20″N, longitude 122°06′23″E; Zhanjiang Guangdong: latitude 21°11′43″N, longitude 110°34′56″E). The number of alleles ranged from 2 to 4, and values of the inbreeding coefficient index (F is ) varied from −0.139 to 0.526. Except for Sa_SNP6 and Sa_SNP10, no significant deviation from the Hardy–Weinberg equilibrium was observed. These novel SNPs will contribute to research design and management approaches for the conservation of S. argus.

Scatophagus argus, a euryhaline fish, is notable for its ability to tolerate a wide range of environmental salinities and especially for its tolerance to a rapid, marked reduction in salinity. Therefore, S. argus is a good model for studying the molecular mechanisms mediating abrupt hyperosmoregulation. The serum osmotic pressure decreased steeply within one hour after transferring S. argus from seawater (SW) to freshwater (FW) and remained at new balance throughout the duration of one week. To explain this phenomenon and understand the molecular responses to an abrupt hypoosmotic shock, hypoosmotic stress responsive genes were identified by constructing two suppression subtractive hybridization (SSH) cDNA libraries from the kidneys of S. argus that had been transferred from SW to FW. After trimming and blasting, 52 ESTs were picked out from the subtractive library. Among them, 11 genes were significantly up-regulated (p < 0.05). The kinetics studies of gene expression levels were conducted for 1 week after the transfer using quantitative real-time PCR. A significant variation in the expression of these genes occurred within 12h after the hypoosmotic shock, except for growth hormone (GH) and polyadenylate binding protein 1 (PBP1), which were significantly up-regulated 2 days post-transfer. Our results suggest different functional roles for these genes in response to hypoosmotic stress during the stress response phase (1 hpt-12 hpt) and stable phase (12 hpt-7 dpt). Furthermore, the plasma growth hormone level was detected to be significantly elevated at 1 hpt and 24 hpt following abrupt hypoosmotic shock. Meanwhile, several hematological parameters, hemoglobin (HGB), red blood cell (RBC) and mean cellular hemoglobin concentration (MCHC), were observed to be significantly increased at 12 hpt and 2 dpt compared with that of control group. Our results provide a solid basis from which to conduct future studies on the osmoregulatory mechanisms in the euryhaline fish.

采用半静水生物测试法，研究亚硝酸盐氮对红鳍东方[鱼屯]（Takifugu rubripes）（95～9．8g）的急性毒性及对部分肝脏抗氧化酶活性的影响。结果表明，在急性毒性实验中，亚硝酸盐氮对红鳍东方[鱼屯]的24、48、72和96h半致死质量浓度（LC50）分别为20188、19057、17109、15925mg／L，安全质量浓度为1592mg／L；在亚急性毒性实验中，当红鳍东方纯分别在5．3、106，159、212mg／L亚硝酸盐氮中暴露4周时，其肝脏总抗氧化能力（T—AOC）、超氧化物歧化酶（SOD）和过氧化氢酶（CAT）活性随亚硝酸盐氮浓度的升高均被显著抑制，差异有统计学意义（P〈0.05），表明亚硝酸盐氮会对鱼体的抗氧化能力产生影响。

In the present study, expressed sequence tag-based microsatellite markers were developed by 454 pyrosequencing for the marine fish Scatophagus argus. A total of 510,939 reads were obtained, and 4,322 di-nucleotides, 1,354 tri-nucleotides, 219 tetra-nucleotides, 30 penta-nucleotides and 9 hexa- nucleotides were detected. Among these repeated sequences, 51 microsatellites where repeat units were greater than 4 were randomly selected to test the variability in natural populations. 12 polymorphic markers were identified and characterized. The number of alleles per locus varies from 3 to 6, and observed and expected heterozygosities ranged from 0.102 to 0.658 and from 0.124 to 0.691, respectively. No genetic linkage and significant departure from Hardy–Weinberg equilibrium were detected among these loci. High-throughput pyrosequencing allows fast and efficient isolation of microsatellite markers on a large scale, and can provide enough microsatellite markers for population genetic studies and genetic mapping.

Experiments were conducted to determine copper accumulation,SOD and lysozyme activities,immune-related genes(Toll receptor mRNA and Lysozyme mRNA) expression level and Vibrio-resistant ability of white shrimp Litopenaeus vannamei fed the diet with different copper levels(via adding copper methionine 0,30 and 50 mg Cu/kg) for 7d,14d and 21d,respectively.The results indicated that the copper content in hepatopancreas of shrimp significantly increased(P0.05) with increasing dietary copper and feeding time.Copper content in muscle was always significantly lower than that in hepatopancreas(P0.05).There was no significant difference in lysozyme activities in hepatopancreas,muscle and haemolymph of the shrimp among different copper treatments(P0.05),although SOD activity of the shrimp was affected by dietary copper level as well as feeding time.The SOD activities in muscle,haemplymph and hepatopancreas of the shrimp treated with 30 mg Cu/kg diet for 21d were significantly higher than those of the shrimp treated with 50 mg Cu/ kg and 0 mg Cu/kg diets.The dietary copper level did not affect the lysozyme mRNA expression level in shrimp’s gills,but it significantly affected the Toll receptor mRNA expression level in shrimp’s gills(P0.05).The Toll receptor mRNA expression level in shrimp’s gills increased significantly(P0.05) with an increasing dietary copper for 7d(P0.05).While the shrimp treated with 30 mg Cu/kg diet showed the highest Toll receptor mRNA expression level in gills for 14d and 21d.The shrimp treated with 50 mg Cu/kg diet for 7d or with 30 mg Cu/kg diet for 14d displayed the largest half lethal time and complete lethal time when the shrimp were artificially infected with Vibrio alginolyticus.It is therefore suggested that dietary copper level affected not only the accumulation of copper in shrimp tissues,but also the SOD activity and Toll receptor mRNA expression level of the shrimp and finally affected the Vibrio resistance of the shrimp.

Experiments were conducted to study the effects of dietary zinc supplementation on the immune gene expression and immunity and disease-resistant ability of white shrimp(Litopenaeus vannamei).The shrimp were fed with 3 zinc methionine diets(supplemented at 0,50,150 mg Zn/kg diet respectively)respectively for 14 days.Then the expressions of Toll Receptor mRNA and lysozyme mRNA in gill and superoxide dismutase(SOD)activity and lysozyme(LSZ)activity in hepatopancreas,muscle and haemolymph were assayed respectively.The shrimp treated with different zinc diets were also challenged with Vibrio alginolyticus.The results showed that the zinc levels in hepatopancreas and muscle of shrimp significantly increased(P0.05)as the dietary zinc increased.While the hepatopancreas accumulated more zinc than muscle.Compared to those of the shrimp in 0 mg Zn/kg and 150 mg Zn/kg treatments,the expressions of Toll receptor mRNA and lysozyme mRNA in gill of the shrimp in 50 mg Zn/kg treatment were significantly up-regulated.The lysozyme activities in muscle,hepatopancreas and haemolymph of the shrimp in 50 mg Zn/kg treatment were significantly higher than those in 0 mg Zn/kg treatment(P0.05).The SOD activities in hepatopancreas and haemolymph of the shrimp in 50 mg Zn/kg and 150 mg Zn/kg treatments were also higher than those in 0 mg Zn/kg treatments(P0.05).While the SOD activity in muscle of the shrimp treated with 150 mg Zn/kg was significantly higher than those treated with 0 mg Zn/kg and 50 mg Zn/kg respectively.The half lethal time and complete lethal time for the shrimp in 50 mg Zn/kg treatment were longer than those in 0 mg Zn/kg and 150 mg Zn/kg treatments after being challenged with V.alginolyticus.It is therefore suggested that compared to those in 0 mg Zn/kg and 150 mg Zn/kg treatments,the shrimp fed the diets added 50 mg Zn/kg(the content of zinc in diet was 73.25 mg Zn/kg)had improved immunity and Vibrio-resistant ability.

This paper introduces nutritional value of corn gluten meal(CGM),and reviews the effects of CGM on growth performance,palatability,apparent digestibility and balance of amino acids of the CGM or the feeds,body biochemical index,muscle composition and aquatic environment when the aquatic animals were fed with the diets containing CGM.The ways to improve the utilization of CGM by aquatic animals are also discussed.It should be further researched focusing on metabolism of CGM in different aquatic animals,effect of the replacement of fish meal by CGM on disease resistance,immunity and meat flavor.With rising raw material prices,the replacement of other animal proteins execpt fish meal by CGM will be of significance.

A Chlorella strain 2003ZGH023 was cultured at modes of photoautotrophic(light,basic nutrient formula),mixotrophic with high carbon level(light,basic nutrient formula,8 gram organic carbon per liter),mixotrophic with low carbon level(4 gram organic carbon perliter),and heterotrophic with low carbon level(darkness,basic nutrient formula,4 gram organic carbon per liter) respectively.The effects of different trophic modes on the growth performance and nutritional composition of the Chlorella were studied.The results indicated that the addition of organic carbon in culture medium significantly increased the cell density and biomass of the Chlorella.The heterotrophic group had a cell density as high as 54.73×106 cell/ml,and biomass of 6.86 g(dw)/L.The sizes of the Chlorella cells in heterotrophic and mixotrophic groups were larger than that in autotrophic group.The assays on nutrition showed that the protein content of the Chlorella cell declined significantly while the total fat content increased significantly in the heterotrophic modes.The crude protein contents in the photoautotrophic mode,mixotrophic mode with high carbon level,mixotrophic mode with low carbon level and heterotrophic mode were 41.88%±0.14%,24.60%±0.07%,21.93%±0.13% and 12.91%±0.35% respectively.The variation of amino acid content in cell at different trophic modes was consistent with that of crude protein.The total lipids in the mixotrophic mode with high-carbon group(15.32%±1.58%) and the heterotrophic mode with low-carbon group(14.15% ± 0.93%) were significantly higher than those in the mixotrophic mode with low-carbon group(12.35% ± 0.25%) and the photoautotrophic mode(10.04% ± 0.3%).There were significant differences in fatty acid compositions of cell cultured in different trophic modes.Fatty acids 18∶3n3 and 14∶1 were dominant in photoautotrophic Chlorella.Fatty acids 14∶1 and 18∶1n9 were the majority in the mixotrophic modes.Fatty acids 18:1n9 and 16:0 were the most abundant in the heterotrophic mode.

The effects of corn gluten meal(CGM) as a partial replacement of fish meal in diet on the growth and muscle composition of Macrobrachium nipponensis were studied.The experiment diets contained a gradient of CGM such as 0%(the control),3%,6%,9%,12% and 12%+0.1%MHA-Ga respectively.All diets were fed to the shrimp triplicately.In the first phase of the experiment,diets were fed to juvenile shrimp(initial body weight of 0.12±0.04 g) for 30 days,and in the second phase diets were fed to juvenile shrimp(initial body weight of 0.23±0.12 g) for 23 days.Growth,survival rate and the muscle composition of M.nipponensis were determined.The results indicated that there was no significantly difference in relative growth rate and survival rate among the treatments(P0.05)although there was a tendency of declining relative growth rate with the increment of the partial replacement.The nutrition assays of the shrimp muscle indicated that there were no significant effects of the partial replacement on water content,total lipid,crude ash,total amino acid(TAA)and total essential amino acid(TEAA)of the shrimp muscle(P0.05).The poly-unsaturated fatty acid and DHA+EPA proportion in total fatty acid profiles of the muscle obviously decreased as the amount of CGM in diet was more than 9.0%.

Changes of body lipid content and fatty acid profile in cultured juvenile silver pomfret(Pampus argenteus) were analyzed.The results showed that body lipid content in the initial of juvenile stage was relatively low,and increased with the growth of the juvenile.The lipid content from July 30th to September 15th was significantly higher than that from June 25th to July 15th(P0.05).In the initial of juvenile stage(in June),the saturated fatty acid(SFA) content in body was relatively low,and significantly lower than that from July to September(P0.05).The poly-unsaturated fatty acid(PUFA) and highly unsaturated fatty acid(HUFA) contents in the initial of juvenile stage were relatively high,and with the growth of the juvenile,the PUFA and HUFA contents reduced.The EPA and ARA contents from August to September were significantly lower than those in June.However,the DHA content did not significantly change from June to September(P0.05).

This paper investigated the lipid contents and fatty acid compositions of ovary, liver and muscle of the wild-caught broodstocks of Pampus cinereus in IV stage of ovary development with body weight from 408 g to 614 g from the East China Sea. The results indicated that there were significant differences of lipid contents and fatty acid compositions among ovary, liver or muscle tissues. The average lipid contents of ovary, liver and muscle of the broodstocks were 45.10%, 30.61% and 19.56% respectively. The lipid content in ovary was relatively stable while in liver and muscle was significantly variable among different broodstocks. There was a positive interrelation of lipid content between liver and muscle. The main fatty acids in ovary of the broodstock were as follows:C16:0C22:6n3C18:1n9C16:4n3C18:0. While C16:0C18:1n9C22:6n3C18:0C14:0 in muscle and C16:0C18:1n9C18:0C22:6n3C14:0 in liver respectively. The contents of DHA (22:6n3) and EPA (C22:5n3) of ovary, liver and muscle were 18.887% and 3.268%, 5.856% and 0.707% and 9.672% and 2.407% respectively. The compositions of C16:4n3,C22:6n3,PUFA,HUFA in ovary were significant higher than those in muscle and liver. The ratios of DHA/EPA/ARA in ovary, muscle and liver were 5.90/1/0.44, 4.03/1/0.50 and 8.51/1/0.85 respectively. The ratios of n-6PUFA/n-3PUFA in ovary, muscle and liver were 5.89, 3.51 and 4.67 respectively. Therefore these data will be useful for the artifical cultivation of the broodstocks of Pampus cinereus.