Abstract:To detect the reproductive characteristics and condition status of Coilia mystus (Linnaeus)in the Changjiang River estuary, a total of 2 138 specimen were collected during breeding season in 2005, 2006, 2008 and 2009, and the biological parameters of C.mystus including body length, body weight, gonad weight, liver weight, fecundity etc. were measured. The results showed that (1) Body length of the samples ranged from 61.2 to 195.0mm,body weight ranged from 2.1 to 32.7 g; and female weighted more than male, especially in the years of 2008 and 2009. The weight difference between male and female became greater with the increasing of body length. The growth rates were different among years,with the lowest value in 2006. (2) There were close relationship between the reproductive capacity and the body length and body weight. The gonad development was the best in 2005, and the worst in 2006. (3)Liver weight of the samples showed positive correlation with the body length and body weight, and there were dimorphism between the sexes: the liver weight of female weighted more than male of the same body length. The condition factor(K) of the C.mystus showed the same trend in both sexes and the smallest condition factor was found in 2006; no apparent variations were observed in other years. There were also no significant difference between fat body weight and fat index between the sexes. In other words, the population of the C.mystus had higher condition factor (K), greater body length and body weight, yet lighter gonad in 2006. The year of 2006 experienced less river discharge and higher temperatures than many former years. While 2005 was the second warmest year in history record, and the samples showed slow growth, good condition ingonad instead, and condition factor did not decrease rapidly. In conclusion, the reproductive characteristics and body condition of the short life species C. mystus varied greatly in different years, which may be caused by yearly weather changes in the Changjiang River estuary.

Abstract:Based on the data from bottom trawl surveys in June, August，and October， 2006, the structure and distribution of macroinvertebrate resources in the Changjiang River estuary and its adjacent waters were analyzed. Totally 49 species of macroinvertebrate were caught, belonging to 2 classes, 5 orders, 25 families, and 37 genus. Crabs accounted for 58.20% in biomass, and shrimps accounted for 92.41% in individual number. Biomass distribution of macroinvertebrate differed by survey time. The relationship was not significant between the density distribution and single environmental factor, such as water temperature, salinity, water depth, pH, dissolved oxygen etc. Relatively, water temperature and salinity have more influence on the density distribution of macroinvertebrate than other environmental factors.

Abstract:The crossbreed F1 progenies of Paralichthys dentatus♂×P. olivaceus♀ have been cultured since 2006 in indoor tanks. The F1 fish (27~33cm in total length) and their parents were randomly sampled for morphological measurements. There were no significant difference for morphological parameters between F1 fish and their parents. In addition, heterosis was manifested by ratio of body length and total height. The pigmentation and stripes on the body surface of F1 were different from their parents. Peripheral blood was sampled from F1 progenies and their parents respectively by withdrawing from tail vein. The DNA contents of erythrocytes in peripheral blood were determined using PARTEC Cell Counter Analyzer(CCA-Ⅱ). The DNA contents of F1 fish, P. dentatus and P. olivaceus were 1.51±0.02pg, 1.50±0.04pg and 1.43±0.16pg respectively. The DNA contents of F1 fish were similar to their male parents, P. dentatus, indicating that the heredity of F1 fish may bear more close relationship with P. dentatus. Meantime, the results showed that the F1 fish were diploid.

Abstract:Embryonic and early larval development and growth of Epinephelus septemfasciatus,including morphological features and developmental period, were observed and studied. Starvation tolerance test was also conducted and other index such as larvae survival and growth, yolk sac, and oil globule utilization rate were recorded under the condition of water temperature 22±0.5℃ and salinity 30. Based on the obtained data, the embryonic development of E.septemfasciatus was divided into five stages, namely cleavage stage, blastula stage, gastrula stage, neurula stage, as well as organogenesis stage. The embryos hatched at 38h45min after fertilization in seawater at 20.5±0.5 ℃ and salinity of 30.0. The whole length of newly-hatched larva was 1.059±0.07 mm. The yolk sac of larvae disappeared 4d post hatching at a whole length of 2.27~2.36 mm, and air bladder of larvae formed during 8~15d post hatching. Then the soft rays of caudal fin developed finally at 30d post hatching.Newly-hatched larvae showed 100% mortality after 7 days of starvation, and the half mortality time was 5d and themortality peaked at 4~6d post hatching. The growth of yolk sac larvae can be divided into three periods: rapid growth period of newly hatched larvae, slow growth period before and after the disappearance of yolk sac,and negative growth period afterwards due to the lack of exogenous feeding. Starvation magnified the difference of growth between starved and normal larvae (P<0.05). Larvae had shorter soma length, bigger head and thinner body after a period of food deprivation. The rear part of head sunk after long-time starvation.

Abstract:The Nile tilapia Oreochromis niloticus is a species of great commercial interest in the world. Although various approaches have been introduced to improve productivity,difference in growth between male and female fish is still the major bottleneck for tilapia cultivation. Therefore,high-frequency or all male stocks are preferred to enhance overall productivity of Nile tilapia. In order to investigate the effect of high-temperature treatment on the sex differentiation in Nile tilapia and screen high and low frequency families of males, 20 families were established for Nile tilapia “Ji-Fu” strain. During the reproductive season of Nile tilapia, the 2~3 year-old Nile tilapia females and males were cultivated in 10 m3 pond. The female mouth was checked to see whether there were fertilized eggs or not every 5~7 days. If there were fertilized eggs, the eggs were taken out, cultivated in a single tank, and named as a family. Fry were counted at 9 d post-fertilization and the every batch of offspring was divided into two groups: control group and high-temperature group. The control group was maintained at a constant 28°C water temperature, and the high-temperature group at 36°C. Treatment durations were 12 d, and at the end of the treatment, the number of fish in each group was recounted.Treated fry were gradually adapted to 28°C, and then all the fry was transferred into tanks in natural water temperature. Progenies were subjected to sexing at ages of 2 to 4 months. Sexing was conducted by observing the morphology of gonadal cell under microscope. The mortality of fry in control group and high-temperature group was not significantly different. Among 20 families, the frequency of males in high-temperature group was significantly higher than that in the control group in 3 families,including F27(88% in treated group; 49% in control group), F37(90% in treated group; 53% in control group), and F41(91% in treated group; 53% in control group). The high-temperature treatment did not significantly increase the male frequency of most families. However, the frequency of males in high-temperature group was significantly lower than that in the control group in 2 families: F8 (43% in treated group; 46% in control group) and (29%in treated group; 38% in control group). These results prove the possibility to modify the sexual ratio of Nile tilapia and provide new methodology to breed new strain with high frequency of males.

Abstract:Seahorse aquaculture is challenged by insufficient feeding supply and lack of knowledge of nutritional requirements, resulting in low survival rate and poor economical profitability. We report here an integrated eco-aquaculture system in which the seahorse and its natural prey were co-cultured with red alga Garcilaria lichevoids in cement ponds. Urea (10 g/m3)and chicken manure (50 g/m3) were used to fertilize the water. Seahorse juveniles were stocked at 200 ind./m3after 5~7 days. After 4 weeks, red alga was transplanted into these ponds to regulate water quality and light, and provide holdfast. The density of red alga was controlled between 0.5 and 2 kg/m3. The introduction of alga provides habitats for small crustacean. Within the macroalgal clusters, small crustacean was over 450 individuals per 100 g of fresh alga. After breeding of 146-day period, seahorse survival rates were 70.8% and 42.5%, and body lengths of seahorse were 11.13 cm and 10.04 cm in integrated eco-aquaculture system and monoculture, respectively. This system incorporated traditional Chinese aquaculture technique of cultivating live feed by fertilizing the water. Results from the experiments suggest that the integrated system is technically feasible, suitable and exemplary.

Abstract:The aim of this study was to set up a high level prokaryotic expression of heat shock protein 90(HSP90) of Exopalaemon carinicauda in E. coli Rosetta. The HSP90 gene of E. carinicauda was cloned into prokaryotic expression vector pET-30a, which was confirmed by double-endonuclease digestion and DNA sequencing. The recombinant vector was transformed into E. coli Rosetta and was induced to express under different temperatures, durations, IPTG concentrations and OD600. The expressed product was identified by SDS-PAGE and an 82.7 kD protein (determined by mass spectrometry) was found. The expression level varied under different conditions. The optimal expression was achieved under induction conditions of 1 mmol/L IPTG,37℃, OD600=0.58, and 7 h.

Abstract:With the increasing price of kelp, sustainable food and suitable feeding strategy are becoming important in the abalone culture industry. In this experiment, Haliotis discus hannai Ino were sized into three groups, A (41.40±2.05mm), B (54.22±2.66mm) and C (63.17±2.52 mm) respectively, and fed with four dietary treatments. Energy budget of various stages were measured and calculated. The mixed-diet treatments showed more organic matter intake than groups fed on kelp alone, indicating that they could get more energy for metabolism. According to the energy budget equation, growth energy of group fed on mixed diet was significantly higher than that of the group fed on kelp alone(P＜0.05), especially in group 1 and group 2. Level of growth energy was high in all of the experimental groups, and the feeding methods were worthy to be used in the abalone culture industry.

Abstract:Polyculture of sea cucumber Apostichopus japonicus and Gracilaria lemaneiformis was conducted in land-based enclosures at orthogonal design during May~July，2010. A. japonicus was cultured at densities of 15,20,25 ind/m2 without feed,and G.lemaneiformis was cultured at densities of 0,180,360 g/m2. The growth and survival of A. japonicus and G.lemaneiformis were compared for different treatments and the changes of environmental nutrient were also detected. The results showed that the final average weight (Wf) , daily weight gain (Mdwg) and Specific Growth Rate (SGR) of A. japonicus were significantly affected by the density of A.japonicus . Wf, Mdwg and SGR of A. japonicus were not significantly affected by the density of G. lemaneiformis. The highest Wf, Mdwg and SGR of A. japonicus were obtained when the density of A. japonicus and G. lemaneiformis were 15 ind/m2and 360 g/m2 respectively. The highest yield of G. lemaneiformis was acquired when the density of A. japonicus and G. lemaneiformis were 25 ind/m2 and 360 g/m2 respectively. The highest SGR of G. lemaneiformis was obtained when the density of A. japonicus and G. lemaneiformis were 25 ind/m2 and 180 g/m2 respectively. The analysis of water quality showed that the content of total nitrogen and total phosphorus in mud declined most sharply when the density of A. japonicus was 15 ind/m2. In summary, polyculture of A.japonicus and G. lemaneiformis could improve water quality and increase the SGR of A. japonicus.

Abstract:Five different pond cultivation patterns of Gracilaria bursapastoris were set and the effects of temperature,salinity, pH, and illumination intensity on the growth of algae were examined. The results indicated that water temperature and illumination intensity had significant influence on the growth of G.bursapastoris. The effects of salinity and pH were slight. The conditions of water temperature of 20~30℃,illumination intensity＜3,000 lx,100% water exchange per 64h,bottom sowing at a water depth of 3m were suitable for the growth of G. bursapastoris. The growth rate was greatly improved when periodical thinning was carried out.

Abstract:Undaria pinnatifida is a commercially important seaweed in China with a more than 30 years of farming history. However, artificial seedling production of this seaweed has not yet been stable. How to control the light intensity according to seasonal changes of temperature is the key to the success of artificial seedling production in practice. In this investigation, we report our large-scale indoor artificial production of seedlings by use of spores at room temperature in Liaodong peninsula, the major farming area of U. pinnatifica in China, mainly on how to control irradiance levels during the 3-month period. According to the requirements of the gametogenesis resulted from our previous studies, we adopted two high irradiance phases (≥50 μmol photons /m2·s) at the beginning and the ending stage. The first high light phase started from seeding of zoospores and ended at the beginning of over-summering phase. This period allowed a full growth of male and female gametophytes. The second high light phase, starting from the end of the over-summering period to the end of the seedling production, allowed a rapid gametogenesis and formation of sporophytes. Under suitable irradiance the gametophytes were able to complete gametogenesis and produce normal young sporophytes even at temperature as high as 24 ℃. The optimal temperature for the growth of young sporophytes was 20~22 ℃. 2~5 mm sporophytes could temporarily tolerate 24~26 ℃, however, the smaller they were, the higher the capacity they demonstrated in tolerating higher temperature. Real-time manipulation of irradiance according to the temperature changes and the development of gametophytes over a period of 3 months generated very good results of seedlings on strings in 2010. This investigation will shed light on improvement of techniques in terms of seedling production in this region.

Abstract:The effect of fish protein hydrolysate(FPH) was examined as an immuno enhancer on the non specific immune response of Penaeus chinensis. P.chinensis were fed with 0%, 5%, 10%, and 15% FPH replacing fish meal protein for 30 days. Samples were collected at the end of the experiment.The results showed that the acid phosphatase activity in the hepatopancreas of P.chinensis fed diet with 5% FPH replacing fish meal protein was significantly higher than that of other groups (P<0.05)，and total haemocyte count of this treatment was significantly higher (P<0.05) than those of other treatments.The activities of acid phosphatase,alkaline phosphatase and lysozyme in the serum of P.chinensis fed with 5% FPH replacing fish meal protein were significantly higher (P<0.05) than those of other groups. Moreover,the group of 5% FPH replacing fish meal protein resulted in a significant SGR increase(P<0.05). In conclusion, fish protein hydrolysate could significantly improve the non-specific immune response of P.chinensis.

Abstract:For rapid, accurate and high throughput detection of Haplosporidium nelsoni, pyrosequencing analysis coupled with PCR amplification of the target sequence was developed. H. nelsoni DNA sequence was obtained by the OIE reference PCR method. Pyrosequencing special primers were designed targeting the conserved region of the sequence. The DNA of Haplosporidium-positive oyster samples was chosen to amplify the target sequence using pyrosequencing primers, and the sequence was analyzed by PyroMarkTM ID System. BLAST online showed that the sequence was specific for H. nelsoni. Oyster samples were detected by both the PCR-pyrosequencing method and the OIE reference PCR method. The results showed that the PCR-pyrosequencing detection method could identify H. nelsoni and the result was consistent with the OIE reference PCR examination. The method meets the requirements of H.nelsoni quarantine and provides a new approach for the examination of other animal diseases.

Abstract:One unique and highly compartmentalized sea cucumber superoxide dismutase gene MnSOD has been cloned and characterized. The full-length MnSOD cDNA of sea cucumber was comprised of 955bp, containing a 672bp open reading frame (ORF), 216bp 3′UTR and 67bp 5′UTR. The full-length MnSOD cDNA had an ATTTA deoxyadenosine monophosphate signal sequence in 3′ UTR and a polyA in the end, which is consistent with the characteristics of effective length of gene translation. Sequence comparison showed that the MnSOD shares 61%~69% similarity with MnSOD of Homo sapiens, Bos taurus, Gallus gallus,Xenopus laevis,Danio rerio,Haliotis discus,Argopecten irradians,Fenneropenaeus chinensis,and Drosophila melanogaster.The full-length MnSOD cDNA encoded 223 amino acids with protein molecule of 24.64 kD, andisoelectric of 6.66. The SOD had 17 alkaline amino acids, 20 strongly acidic amino acids, 83 hydrophobic amino acids, and 59 polar amino acids. The protein sequence had no signal peptide or transmembrane structure, only a mitochondrial leading peptide. The secondary structure was mainly comprised of alpha helix, with the largest number of irregular coiling and chain in the whole protein, without folding. The InterPro software analysis showed that the sequence of amino acids contains three protein kinase C phosphorylation sites, one casein kinaseⅡ phosphorylation site, 5 nutmeg acylation sites, and an SOD family signature peptide DVWEHAYY. The protein had 1 serine and 3 threonines, which were possibly protein kinase phosphorylation sites. Disulfide bond analysis showed that MnSOD contained three cysteines , forming a disulfide bond by connecting the 17th and 107th Cysteines. The cloning of MnSOD cDNAwould be helpful for better understanding of the body defense system to eliminate active oxygen O-2and maintain the metabolism balance.

Abstract:An artificial reef is one or more objects of natural or human origin deployed purposefully on the seafloor to influence physical, biological, or socioeconomic processes related to living marine resources, which is applied to improve marine environment and protect fishery resources.Large numbers of artificial reef projects have been carried out in China since the beginning of 21st century, so as to restore marine habitat. It is practically very important for future construction of the artificial reefs that the fishery resources enhancement of the artificial reef can be scientifically evaluated. There are 3 types of fish and macro-invertebrates (i.e. Type I,Ⅱ,and Ⅲ) in artificial reef area.Type Ⅱanimals inhabit surrounding areas and do not contact artificial reef, whose biological data can be obtained by trawling. Based on the survey data of fishery resources in artificial reef area of Shengsi in Zhejiang Province, the density of fishery resource is analyzed, and the variation tendency of the fishery resource density is simulated by using improved Logistic model. The parameters of the model are calculated via Genetic Algorithm method. The result indicates that the original ecological carrying capacity is approximately 6.00~8.03 ind/km·kW, and the enlarged carrying capacity is approximately 4.4~5.89 ind/km·kW of type Ⅱfish and macro-invertebrates in the artificial reef area. The carrying capacity has periodically fluctuated along with the change of seasons.

Abstract:Marine environment is a grey system. Applying the grey clustering method to assessing the eutrophication of marine environment is to establish a comparatively perfect model for marine environment evaluation and give a sound assessment for the quality of marine environment, thus, providing evidence for marine environment management. Referring to Chinese Seawater Quality Standard (GB3097-1997) and the characteristics of seawater eutrophication, selecting PO3-4-P, DIN, DO, COD and Chl-a as evaluation indexes, and classifying seawater eutrophication into three levels, then using the whitenization weight function to describe its grading sideling and determine the clustering weights, coefficients and their grades of the corresponding indices in the grey system, a comprehensive evaluation model was established.Taking Jiaozhou Bay as the subject, through the analysis of the data in Jiaozhou Bay in May and August of 2009, the result showed that the eastern Jiaozhou Bay was in the state of eutrophication, the western and northern water was in the state of medium-level nutrient, and the center and mouth of the bay was oligotrophic. The state of water quality was closely related to the river runoff, industrial and agricultural discharge, domestic sewage, aquaculture wastewater, water exchange rate and the water depth. The eutrophication state evaluated by the grey clustering method can reflect the real situation of Jiaozhou Bay, indicating that the assessment of seawater eutrophication by the grey clustering method is feasible.

Abstract:An investigation on concentrations of dissolved petroleum hydrocarbons (DPH) in the surface water of northern Yellow Sea of China has been conducted in spring, summer, autumn, and winter during Jun. 2006~Oct. 2007. Based on the acquired data, the seasonal variations and distribution characteristics were analyzed. The results showed that the annual mean concentration of DPH in the surveyed area was 0.050 mg/L, within the concentration limit of Grade I (Ⅱ) according to National Seawater Standard. The seawater was slightly contaminated and the concentrations of DPH varied seasonally. The highest average concentration (0.099 mg/L) appeared in summer, which was classified as Grade Ⅲ seawater. The average values in spring (0.022 mg/L) and autumn (0.027 mg/L) were much lower, within the concentration limit of the Grade I (Ⅱ) seawater. The average value in winter (0.051 mg/L) was slightly beyond the concentration limit of Grade I (Ⅱ) seawater. Based on the data of the seasonal variation and distribution characteristics, it was concluded that the concentrations of DPH in Bohai Strait, ports and the northernern Yellow Sea were relatively higher, and those near Changshan Islands were lower.

Abstract:Situation of trawl gears and fishing methods in 32 major fishing ports and villages, and 5 fishing gear plants, distributed along the coast of Yellow Sea and Bohai Sea area,have been investigated or visited in the terms of working principle of fishing equipment, fishing season, fishing grounds, fishing equipment allocated proportion, fishing vessels power etc.during June~July, 2010.Also, the situations of circumference of net mouth, net total length, net mouth mesh size, and the smallest mesh size of cod-end were surveyed. All types 25000 trawlers were found in surroundings of the Yellow Sea and Bohai Sea area, and the proportion of small trawlers reached as high as 80%, mainly distributed in the Bohai Sea area and some inshore waters of the Yellow Sea. Totally 34 kinds of trawl nets were found: 7 kinds of the small single-vessel ground-trawl with double-wings and single-cod-end, 1 kind of the small single-vessel floating-trawl with double-wings and single-cod-end and,1 kind of the small double-vessels ground-trawl with double-wings and single-cod-end, 2 kinds of the small double-vessels floating-trawl with double-wings and single-cod-end, 1 kind of the single-vessel beam trawl with double-cod-ends, 5 kinds of the single-vessel beam framework trawl with single-cod-end, 5 kinds of the medium single-vessel ground-trawl with double-wings and single-cod-end, 2 kinds of the large-scale single-vessel ground-trawl with double-wings and single-cod-end, 2 kinds of the large and medium-scale single-vessel floating-trawl with double-wings and single-cod-end, 3 kinds of the medium double-vessels ground-trawl with double-wings and single-cod-endand 5 kinds of the large and medium scale single-vessel floating-trawl with double-wings and single-cod-end.The trawling intensity greatly exceeds the reproduction capacity of fishery resources, and the fishing yields are of low-value and immaturity.Subsistence fishing and commercial fishing at the same time also showed the prominent contradictions. The mesh size of wing and net mouth is getting bigger, the mesh size of cod-end is getting smaller, and the entire trawl gear shows a tendency of size increase. The largest mesh size of wing is 16 000mm, the largest mesh size of net mouth is 15 000mm, the circumference of net mouth is 840m, the net total length is 170m, the smallest mesh size of cod-end is 40~45mm or 18~20mm, and the individual minimum mesh size of cod-end is only 6~8mm. The seabed and benthic organisms were seriously damaged by ground wire of the beam framework trawl and the bow-frame trawl. The fishing equipment needs standardization and calls for scientific research.

Abstract:The life-cycle of the scyphozoan Cassiopeia andromeda was described. The tropical jellyfish alternates between a sessile, asexually propagating polyp form and a typically pelagic, sexually reproducing medusa. Major events in the metagenesis are not autonomous, but depend on the presence of and interaction with special physical, chemical or biological factors. The still water and interaction between mature individuals are important for spawning and fertilization. Scyphistoma is produced by metamorphism from oosperm and planulae. Medusa comes into being within a permissive temperature and light by monodisk strobilation. Budding increases the number of scyphistoma when the temperature is above 20 ℃. Four arms have shaped in the course of strobilation. And the young jellyfish can stand upside down in 12~24 h. Zooxanthellae supplies much energy for scyphistoma and medusa besides feed such as Artemia. In our laboratory, scyphistoma has been kept for a long time and medusa may live for over 2 years.