Abstract:Growth, distribution and abundance of released Fenneropenaeus orientalis were studied based on the data collected in the Bohai Sea from May to October in 2009. The collection and statistics of total yield of F. orientalis was carried out by the provincial institutes at the end of October. Results showed that the released F. orientalis mainly distributed in the shallow water (1-2 m) and estuary areas in mid June, and distributed at the depth of 5-18 m at the end of July, especially 10-15 m. The mean weight of F. orientalis were 2.5 g in mid June, and reached 7.0 g from the beginning to mid July, 20.0 g from the end of July, 27.0 g from the end of July to the beginning of August, 36.0 g in mid August and 41.0 g at the beginning of September. Based upon the survey data, the estimated biomass of F. orientalis in the Bohai Sea was 1 665 tons in August and reduced to 137 tons in October after being captured. The abundance of F. orientalis in the bays of the Bohai Sea was 129.9, 7.8, 0.3, and 0.05 ind/net•h respectively, which were positively related to the released numbers. Based on the collection and statistical data, the total yield of F. orientalis in the Bohai Sea was 2 377 tons and the estimated recapture ratio was 2.8% in 2009.

Abstract:Community structure and spatial distribution of the particle-attached bacteria along environmental gradient in the Pear River Esturary, as well the influencing factors, were studied by PCR-DGGE and canonical correspondence analysis. The DGGE profiles showed significant spacial succession of the particle-attached bacteria along environmental gradient. Some bands from DGGE gel were shared by two or more stations, while the others belonged to the special station. The bacterial communities in S4 and S5, differed significantly from those in adjacent stations, with transitional form from the freshwater-seawater mixing zone to seawater zone. Sequence analysis of nineteen major bands from DGGE profiles revealed that two sequences were highly similar to those of the cultured bacteria (≥99%), and the others were similar to those of the uncultured bacteria (91%～100%). Proteobacteria and bacteroidetes were dominant populations in all stations, particularly proteobacteria (78.9%). Canonical correspondence analysis indicated that nitrogen nutrient and salinity were the major contributing parameters for the spatial distribution of the particle-attached bacterial community structure in the Pear River Esturary.

Abstract:Statolith microstructure and growth characteristics were studied in 491 specimens (274 females and 217 males) of short-fin squid Illex argentinus collected by the Chinese jigging fishing fleet in 2007, 2008 and 2010. The results showed that growth increments of I. argentinus consisted of light and dark lines, with the initial point of increment formation (focus) being dark and like a drip of water. The growth increments were narrow to wide, light to dark from the focus to lateral dome, and were wide to narrow, dark to light form lateral dome to dorsal dome. Three zones (postnuclear, dark zone and peripheral zone) occurred in statolith dorsal dome. The results of principal component analysis on ten morphologic indices showed that total statolith length (TSL) and maximum width (MW) could be used to distinguish between different groups. There was no sexual dimorphism in the TSL and MW growth between different groups, and the relationship between age and TSL and MW were best described by linear functions for austral winter group and by logarithm functions for austral autumn group, respectively. However, there was a sexual dimorphism in the statolith weight (SW) between different groups, and the relationship between age and SW for females and males were best described by power and exponential functions for austral winter group and by exponential and logarithm functions for austral autumn group, respectively. The absolute growth rate (AGR) and instantaneous relative growth rate (IRGR) of TSL and MW tended to be high at young stages, and then decreased when the age increased. However, the AGR of SW tended to be higher with the increased age, and the IRGR of SW increased in the beginning and then decreased when age increased. The growth rate of austral winter group was higher than austral autumn group, and the growth rate of females was higher than males at the same age.

Abstract:The embryonic and morphological development of larval, juvenile and young kelp bass Epinephelus moara were observed and studied. The morphological features and the developmental phases were described in great detail from fertilization to young fish. The results showed that the time period for embryonic development is 38h 17min at 22±0.2℃, salinity 30, DO 7.8mg/L, and pH 8.25. Based on the obtained data, six periods including 28 stages of E. moara embryo were described, which were cleavage, blastula, gastrula, neurula, organogenesis, and hatching period. After being reared for 5 days in the sea water at 23±1℃, salinity 30±3, DO≥5mg／L, pH 8.0±0.5, the yolk-sac of larvae disappeared and the late larval stage began; after 27 days, the faster growing larvae developed into juveniles; after 65 days, the faster growing juveniles completed metamorphosis and became young fish. The post embryonic development of E. moara was divided into larval stage, juvenile stage as well as young fish stage, based on the features of the yolk-sac, finfold, pelvic fin spine, second dorsal fin spine, scale and body color. Accordingly, the larval stage was further classified into early larvae and late larvae, according to the existance of the yolk-sac, respectively.

Abstract:The annual maturation cycle of testis and variation of sex steroids level in male barfin flounder were investigated by histological and radioimmunoassay methods. The results showed that gametes exhibited five different phases during the annual development cycle, accordingly the testis maturation cycle can be divided into five stages. The biological parameters including gonadosomatic index (GSI), hepatosomatic index (HSI),and condition factor (CF) were also recorded and they exhibited reasonable variation during the testis maturation. The GSI began to increase in October and peaked in December, and then dropped dramatically and maintained until the next maturation cycle. The HSI value was relatively low during the annual cycle except in November and December. The CF value stayed at a high level from May to August and maintained a relative low level at other months. The serum testosterone level increased from September and peaked in December, then dropped to a relatively lower level until the next maturation cycle. Meanwhile, the serum estradiol level peaked in February and maintained at a relatively low level during the annual maturation cycle. These results highlight the reproductive biology of male barfin flounder, and can serve as useful reference for maturation regulation of male broodstocks.

Abstract:The morphology of mature egg and sperm of Scophthalmus maximus, and initial stages of sperm penetration were observed under scanning electron microscopy(SEM). The cortex had been observed with TEM. The micropyle consists of a depressed vestibule and a canal. A lot of small holes were found on the vestibule and the outer chorionic surface. Spermatozoon of S. maximus consists of an acrosome-less head, a short midpiece containing 9-14 mitochondria, and a long tail. The speed of sperm penetration was very fast. During 0-5 seconds post insemination, sperm entered the eggs. During the sperm penetration, there were some structure changes, for example, the sperm became bigger, the mitochondria disappeared, and the jagged circle in the inner wall of the micropyle tunnel turned into slippery circle.

Abstract:Statistical morphological characteristics among three European populations (French, Spainish and Danish) and three Chinese farmed populations (Laizhou, Haiyang and Rizhao) of broodstock turbot, Scophthalmus maximus were revealed and compared on the basis of eight morphological indices using one-way ANOVA, principal components and clustering dendrogram analysis. The morphological difference among six populations was remarkable, but there was no isolation without overlap. The results of one-way ANOVA showed that there was notable difference between French and Rizhao population, Rizhao and Haiyang population were similar in morphology, and Danish population had the high bodily form. In principal components analysis, three principal components were constructed, and the contribution from the first, second and third principal component were 47.07%, 28.10% and 15.45%, respectively. The cumulative contribution rate was 90.62%. The results of clustering dendrogram indicated that the morphological variations of Laizhou and Haiyang populations were little, and they were similar to the French population. Rizhao and Spanish population were similar. The morphological variations between Danish population and other five populations were large. The morphological diversity of three European turbot populations was higher than the three farmed Chinese farmed populations.

Abstract:A feeding trial was conducted to evaluate effects of dietary vitamin C on non specific immunity of larval and juvenile Symphysodon aequifasciatus with supplement of vitamin C in feed(0-2000.0 mg/kg). When the supplementation ratio reached 500.0 mg/kg(group Ⅴ), the alternative complement pathway (ACP) activity, serum lysozyme activity, phagocytosis index(PI) and phagocytosis percentage(PP) of the fish were significantly higher than that of the control (P<0.05), and they increased over time in the same level. And then the non-specific immune index dropped with the increase of dietary vitamin C above 1500.0 mg/kg (group Ⅷ). It was found that proper level of vitamin C supplement in feed may enhance the nonspecific immunity of the larval and juvenile fish, while lack of vitamin C or over-dose may negatively affect the fish health.

Abstract:A 63-day feeding experiment was conducted to evaluate the effects of fish protein hydrolysate as feed ingredient in high plant-protein diets on growth performance and non-specific immunity for Japanese flounder, Paralichthys olivaceus. Fish protein hydrolysates respectively replaced 0 (FM1, negative control， containing 55% soybean meal and 19% fish meal), 0(FM2，positive control， containing 45% soybean meal and 25% fish meal), 6% (FPH6), 11% (FPH11), 16% (FPH16), 21% (FPH21),and 26% (FPH26)of the total protein. The results showed that specific growth rate and protein retention of fish fed with FPH11 was significantly higher than FM1（P<0.05），but was not significantly different from FM2（P>0.05）. For protein digestibility, all the hydrolyzed protein diets were significantly higher than FM1（P<0.05），but was not significantly different from FM2（P>0.05）. Feeding rates of FPH11，FPH16，FPH21 and FPH26 were significantly higher than FM2（P<0.05）. The relative activities of acid phosphatase (ACP) in fish fed with FM1 was significantly lower than FPH26（P<005）. SOD relative activities in all the hydrolyzed protein diet were higher than FM1（P<0.05）, and SOD relative activities in FPH11 was significantly higher than FM2（P<0.05）. Total antioxidative capacity of FPH6, FPH11 and FPH16 were significantly higher than FM1 and lower than FM2（P<0.05）.

Abstract:Brown sugar, Bacillus subtilis, and fermentation solution were added to the indoor intensive culture system of Marsupenaeus japonicus to determine the impacts on water quality, shrimp growth and shrimp survival. The results showed that the flocculation with bio-flocs characteristics, consisting of bacteria, microalgea, protozoa, and amorphous organic detritus, was found under microscope in 14 d in the experimental group. The total amount of inorganic nitrogen in the control group was 56.2 g/m2, while only 4.13 g/m2 in the experimental group. Compared with the control group, the amount of COD and active phosphate increased significantly in the experimental group. The yield of M. japonicus was 0.55 kg/m2 in the control group and 0.65 kg/m2 in the experimental group. The water consumption by 1 kg shrimp production in the control group was 28 t, while only 3.4 t in the experimental group. This study showed that the addition of brown sugar and B. subtilis was effective on water quality control in intensive shrimp culture systems.

Abstract:In this study, pEGFP-N1-ie1 was reconstructed by inserting WSSV immediate early gene, and vp28 was cloned in a new constructed vector. The survival rates and antiviral associated factors (Dicer, Argonaute, STAT and Lyzome) were detected in Litopenaeus vannamei after immunity by injection and oral-feeding. RT-PCR results showed that vp28 was detected in gill of shrimp by injection and oral-feeding immunity treatment. The relative protection rate of vp28 group reached 22.4% (injection group) and 36.84% (oral feeding group).The STAT and dicer mRNA expression in vp28 group were significantly higher than that of control group after injection treatment for 7 d. The argonaute mRNA expression in vp28 group was significantly higher than that of control group after injection treatment for 3 d and then decreased. The lysozyme mRNA expression in vp28 injection group was consistently significantly higher than that of control group. But the STAT and Argonaute mRNA expression in vp28 group was significantly higher than that of control group on the 7th day of oral-feeding treatment and then decreased. The dicer mRNA expression in vp28 group was significantly higher than that of control group on the 3rd day of oral treatment. These results demonstrated that vp28 DNA vaccine has a potential utility for control of WSSV disease in shrimp.

Abstract:In the present study, using the chlorophyll fluorescence technique, the suppressive effect of germanium dioxide (GeO₂)on Nitzschia sp. contamination during the cultivation of Saccharina japonica seedling was investigated with the photosystem II maximum fluorescence yield (Fv/Fm) as the index. The results showed that: 1) When the concentration was above 5mg/L, GeO₂ affected Fv/Fm value of Nitzschia sp. significantly, whereas when the concentration was 15mg/L or above，GeO₂ had lethal effect on Nitzschia sp.; 2) To the young sporophytes of S. japonica, GeO₂ at concentrations of 20mg/L or above affected the Fv/Fm value significantly, whereas GeO₂ at concentrations of 30mg/L or above had lethal effect on young sporophytes; 3) To the young sporophytes contaminated by Nitzschia sp.，the Fv/Fm value was affected significantly by GeO₂ at concentrations of 15 mg/L or above , while the contaminated young sporophytes died when GeO₂ concentration was 20 mg/L or above. Comparatively, GeO₂ at concentrations of 5～15 mg/L could suppress the photosynthesis of Nitzschia sp. significantly, but only had a minor effect on photosynthesis of S. japonica young sporophytes. Therefore, GeO₂ at concentrations of 5～15 mg/L could prevent the Nitzschia sp. contamination during the cultivation of S. japonica young sporophytes. The results obtained from the present study could provide the basis for preventing the Nitzschia sp. contamination during the cultivation of S. japonica young sporophytes.

Abstract:Using Sinonovacula constricta as raw materials, optimum enzyme was selected from trypsin, pepsin, papain, alcalase and neutrase based on the hydroxyl free radical scavenging activity. Based on the single factor experiment, optimization of the hydrolysis conditions was conducted by the response surface methodology. The scavenging activity of hydroxyl free radical was investigated and the molecular weight of the enzymatic hydrolysates of S. constricta proteins was determined by a Sephadex G-15 gel column. The results showed that alcalase had the best hydrolytic effect and the optimum conditions for hydrolysis by alcalase were as follows:6 mg/ml substrate,3% enzyme, pH 8.0,55℃, 4 h. The scavenging activity of hydroxyl free radical of enzymatic hydrolysates was 76.60% and the IC50 was 1.89 mg/ml. The molecular weight of over 80% bioactive peptides from S. constricta was less than 1 500 Da.

Abstract:Survey and field measurements of the stow net fishery in the 32 main fishing ports and villages along Yellow Sea and Bohai Sea were carried out from June to July in 2010. The stow net fishing composition and operation in Yellow Sea and Bohai Sea was studied based on the investigation data listed in the 2009 annual report on the stow net fishing gears and fishing methods issued individually by Provincial Fishery Bureaus of Hebei, Liaoning, Shandong and Tianjin, and data from Chinese Fisheries Yearbook from 1983 to 2009. The results showed that the production by stow net fishing was the highest in 1983 with a yield of 904 300 tonnes and a contribution rate of 17.18%, and was decreased year by year thereafter. Currently, stow net fishery is the major fishing gear and fishing method in the Yellow Sea and Bohai Sea area with an annual production of 381,500 tons and a contribution rate of 10.49%. Now there are 690,000 stow nets in 4 types, 7 styles and 19 kinds operating in the studied area. Among all of the stow nets in three provinces and one city, 53.54% are operating along the coast of Liaoning Province, mainly in the Liaodong Bay; Hebei accounts for 24.69%, mainly in the Bohai Bay; and 23.08% are used along the coast from Rizhao to Yantai in Shandong Province. Among the stow nets, 54.51% are parallel single-net stow nets for the shellfishes, shrimps and trash fishes, and 16.12% are double-anchor vertical-bar stow nets for Acetes chinensis. The minimum mesh sizes of the stow nets are between 4～30mm. The comprehensive analysis shows that stow net is the major fishery method in the studied area with poor selectivity due to small mesh sizes,which is unfavorable to sustainable utilization of the fishery resource in the Yellow Sea and Bohai Sea area.

Abstract:Long-line culture facility in the sea may move and deform under the effect of current. In order to keep the stability and safety of the facility, it is necessary to carry out the dynamic analysis of the whole structure. Herein, a numerical model based on finite element method was developed to reveal the dynamic response of long-line culture facility to the current. The maximum displacement of float and hanging cage and maximum mooring line force were calculated and analyzed. The simulation results showed that the float rope deformed obviously under the effect of current，and the change of shape corresponded with the practical condition. Furthermore, the maximum displacement of float and hanging cage and the both mooring line force increased with the increase of the current velocity under the same flow direction. The maximum value of displacement of float and hanging cage were 7.6 m and 9.6 m, respectively. The maximum displacement of float and hanging cage and the right mooring line force increased with the increase of the current angle under the same current velocity. But the left mooring line force changed slightly under the different current direction, with the maximum value of 3 780N.

Abstract:Based on the nutritional elements data of water surveyed in February，April，June，August，October and December，2009，the distribution and variation of total nitrogen(TN) and total phosphorous(TP) in seawater of the Jiaozhou Bay wetland were studied.The results showed that：（1）In the tidal range of the Dagu River，the content of TN and TP in water roughly decreased from upper stream to lower stream along the river course．In the inter-tidal area of the Jiaozhou Bay wetland，the regions with higher contents of DIN and DIP were basically located at the estuary of Dagu River and the area adjacent to it，and their contents and distribution were mainly controlled by runoff amount of Dagu River entering the sea．（2）There were apparent seasonal variations of TN and TP contents in the water of Jiaozhou Bay wetland．In the tidal range of the Dagu River，the mean content of TN was the highest in December，higher in February and the lowest in August.The mean content of TP was the highest in February，higher in December and the lowest in April．In the inter-tidal area of the Jiaozhou Bay wetland，the mean TN content decreased from February to August and increased from August to December，and the mean content of TP was the highest in February and lower with insignificant variation in other surveyed months．（3）The nutritional elements in seawater such as TN and TP in the Jiaozhou Bay wetland was mainly derived from the runoff of Dagu River entering the sea．

Abstract:A special electrochemical sensor system for detecting malachite green (MG) based on sodium dodecyl sulfate functionalized conductive carbon black paste electrode was established. The electrochemical behaviors of MG at the functionalized electrode were studied. And the effecting factors, including conductive carbon materials, content of the modifying agent, ionic strength and species of the supporting buffer solution, pH, accumulation potential,and accumulation time were optimized. Under the optimized conditions, in the range of 5-200 μg/L ,the dependence of the anodic peak current on the concentration of MG was linear with a detection limit of 1.5 μg/L (signal/noise = 3). This method exhibited high sensitivity, good stability and reproducibility. After a simple pretreatment by filtration, MG in real fresh water samples from fishery environmental was detected. And the results were satisfactory with a 90% average recovery rate.

Abstract:Fish cell culture techniques are important and promising tools for biology studies. With the development of biological technology, an increasing number of fish cell lines have been established. Although the procedures for developing fish cell lines varied with cell sources, basic principles were similar. In this paper, the status of fish cell culture development, application and characteristics as well as culture techniques were reviewed, with emphasis on the perspectives for fish cell culture development.