Abstract:The development process of the circulatory system of Penaeus chinensis has been studied w ith tissue method. At the third stage of nauplius, originating from the part of carapace rudiment, the mesoderm cells of each side of ventral- lateral part of the larva divide quickly and extend towards back to form the heart rudiment cells. Then some of them migrate medially to form a mesodermal plate above the back of the mid- gut. After that, the plate curls towards back to form the heart. Meanwhile, the others extend outwardly to make contact with each side of lateral part and form the pericardial cavities. At the fifth stage of nauplius, the wall of heart slits inward directly to form the ost ia. The shape and the structure of heart improve with the development of the larvae. After the first stage of zoaea, the cells of heart wall develop into myocardial cells. Subsequently, one thin layer of adventit ia formed by the connective tissue cells encloses the myocardium. At the post larva stage, the appearance and the tissue structure of heart are similar to those of adult. The measure and time of development of dorasl abdominal artery are similar to those of heart. The formation of median dorsal artery includes two parts: one part near heart is extended by the heard of heart; another part far away from heart is formed by mesodermal cells in front of nauplius back; hemocytes are observed at the f irst nauplius.

Abstract:The esophagus of disk abalone, Haliotis discus hannai Ino, was studied with histo logical and histochemical methods, scanning and transmission electron microscopic observation, and test s for some enzymat ic activity. The esophagus is divided into anterior, mid and posterior partitions. The mid esophagus is again divisible into two structurally and functionally distinct regions, a central food channel and two lateral pouches. The epithelium of the esophagus consists of five types of cells, ciliated columnar cell, mucous cell, granular gland cell, cell w ith microvilli and secretory cell. Ciliated columnar cells participate mainly in transport of food and secretion, and show structural features of absorptive cells. Mucous cells secrete neutral and acid mucopolysaccharide. Granular gland cells contain a large number of secretory granules. Cells w ith microvilli also show the features of absorptive cells. Secretory cells, the main glandular cells in the lateral pouches, show strong activity of proteinase and non-specific esterase. They may secrete digestive enzymes by the apocrine. The secretory cells may also participate in absorption and intracellular digestion of food. The epithelium of the mid esophagus shows activity of three plant polysaccharide enzymes by test s in vitro .

Abstract:Chromosome segregation in fertilized eggs of pearl oyster , Pinctada martensii Dunker ,following the first polar body (PB1) inhibition with cytochalasin B (CB ) was observed. Cytological observation indicated that the inhibition of PB1with CB changed the normal chromosome segregation pattern. Polypolar segregation patterns were detected in the second meiosis ( M Ⅱ) . There were three typical patterns , namely dipolar segregation (28. 67 %) ,tripolar segregation (40. 56 %) and tetrapolar segregation (23. 78 %) in 3n ♀×2n .group . There were 6. 99 % of treated eggs that could not be classified. When chromosomes divided and segregated equally to each pole in dipolar segregation , tetraploids would be produced , and part of tetrapolar segregation also could produce tetraploid embryos. Aneuploids mainly resulted form triploid segregation . In the untreated group , chromosomes went through normal dipolar segregation ,and two polar bodies were released , but the chromosome number in each polar was highly variable , which gave rise to a variety of aneuploid embryos. The similar chromosome segregation patterns were observed in the group of diploids crossing diploids by blocking PB1 , including dipolar segregation (25.00 %) ,tripolar segregation (21.50 %) and tetrapolar segregation (34.30 %).The remaining 19. 19 % could not be classified. The possible mechanisms for the various types of chromosome segregation are discussed.

Abstract:Chemical composition and net production of cultured bivalves and seaweed (the kelp Laminaria japonica) , and fouling organism in the Sishili Bay , were determined. The investigated cultured bivalve species involved the scallop Chlamys f arreri , the mussel Mytilus edulis , the oyster Grassostrea gigas , the clam Ruditapes philippinarum and Mactra chinensis , and the Ark shell Scapharca suberenata. The investigated fouling animals involved the clam Trapezium liratum , the ascidian Styela clava , Ciona intestinalis , Cnemidocarpa chinensis , Molgula manhattensis and Botrylloides violacens , and the seaweed Ulva pertusa. Samples were collected from different farming zones in the Sishili Bay in late May , 2000. All the investigated cultured bivalves and seaweed had reached commercial size. C content of soft tissue of bivalve species was similar , with the range 42. 2 to 46.0%ofsofttissuedryweight;whileNcontentwassignificantlydifferent. TheNcontentofthesofttissueof C. f arreri was the highest (12. 36 %) , while that of G. gigas was much lower (8. 19 %) . Chemical composition of shells varied with different bivalves. N content of M. edulis and R. philippinarum shells was the highest, 0.55 %and 0.56 %dryweightrespectively. C, H, NandPinmusselshellsaccountedfor 30.4%, 30.2%, 31.8% and 29.6% of the total C, H, N and P respectively. In contrast, the shells of C. f arreri contained only 0. 1 % N , and C , N and P in the scallop shells accounted for only f ascita were relatively high , possibly suggesting deficient N origin. 6. 2 % , 2. 5 % and 6. 9 % of thetotalC,H,NandPrespectively. Indifferentpartofkelp,Ncontentwasalsosignificantlydifferent. TheC/ N atomic ratios in L . japonica and U. In different farming zones , the C/ N ratios in the kelp were also different , indicating different nutrient conditions of the farming zones. In the Sishili Bay, about a 850t N and 78t P were removed every year just through the harvest the ecosystem. Because of the cultured bivalves and seaweed , and the lost of fouling organisms , indicating the effect of aquaculture on considerable amount of N and P was apportioned in mussel and oyster shells , it is suggested that large quantities of mussels and oysters should not be cultivated in oligotrophic coastal region.

Abstract:The influences of food concentration on populat ion fluctuation and production of cannibalism, Asplanchna brightwelli were studied. It was found that, in the cumulative culture , the population dynamic of A. brightwelli fed on Paramecium of concentrat ions ranging from 100 to 400cell#mL- 1 displayed typical 0s0 curves in the course of the experiment , and the relationship between the population persistence production and standing crop were conic function. With reference to food density experiments, there were the highest value of maximum sustained yield( MSY) , capacity ( K) , average production or intrinsic rates of increase of population under 300 Paramecium#mL - 1 in the whole diet concentration, which were 6. 4indiv#mL - 1#d - 1 ( 355mg#L - 1 ) , 13. 7ind# L- 1( 760. 6mg#L- 1) , 55 mg#L- 1 and 1. 4496( d- 1) respectively. In the range of 100- 300cell#mL- 1, the MSY, critical standing crops and the time arrival to MSY or K increased with increment of diet concentration, whereas the above ment ioned indexes decreased in 400cell#mL- 1 of food density. Fed on Paramecium, the value of food rat ion of rotifers changed 146% ~ 707% of body weight , with average 390%; food coeff icient was 19. 8 - 91. 7.

Abstract:GW01 and GW02 were the fusants between Nocardia sp. and Candida sp. through inter-kingdom protoplast fusion using PEG, Ca 2+ , lysozyme and snailase. After analyzing the comparisons of form, resistance to ant ibiotics, heat resistance, acid resistance and the growth rate, GW01 and GW02 could be conf irmed to be the true fusants. The fusants were more widely suitable to the fishery water quality than the parental strains. They could rapidly degrade the harmful compo sition of the water, such as COD, NH 4 , NO-2 , PO3- 4 , improve the concentration of DO and the biodiversity of the microorganisms in the water. The results suggested that the technique of inter-kingdom protoplast fusion might offer ideally new strains for bioremediation for the degeneration f ishery ecology.

Abstract:Aeromonas hydrophila is one of the important pathogenic bacteria of aquaculture. It is significant , therefore , to study the changes on functional genome in its growth cycle. Two2dimensional electrophoresis (22D PAGE) , one of the approaches for proteomics , was used to study protein composition in different phases during the cycle. The result showed that the composition was significantly changed in different phases. The discovery of different pertinent proteins in the different growth phases will contribute to find out the genome expression of A. hydrophila in different growth phases. In this experiment 22D PAGE was compared with normal SDS2PAGE in the same conditions , and the result indicated that 22D PAGE was an effective technique for proteomics study.

Abstract:A recirculating system was designed for shrimp brood stock Penaeus vannamei culture indoor in the low salinity area of the river mouth in Shanghai. The natural seawater with salinity of 9 -12 was mixed with concentrated seawater with salinity of 100 -120 , which made the culture water salinity reach 28 -30. About 200 shrimp brood stock (female∶male was about 1∶1) were cultured in the recirculating system for two months , and the survival rate of the shrimp was about 90 %. Unilateral eyestalk ablation of female shrimp was done for stimulation of the ovary maturation. Three days after the operation the ovary development could be observed clearly , and one week later , a part of shrimp began to spawn , but the eggs were not fertilized. One month later fertilized eggs appeared and nauplius were obtained. The results showed that shrimp brood stock P. vannamei cultured in this recirculating system could live healthily and spawn successfully. The regularity of molting and growth in shrimp brood stock P. vanamei was investigated. Before ablation of eyestalk , the mean molt interval was about 14 ～ 15 days , and after that , the mean molt interval extends to about 20 days due to ovary development. Withmoltingthebodylengthofshrimpbroodstockincreasedcontinuously,whetherbeforeorafter ablation of eyestalk , but the mean daily increase of body length before ablation (female :0. 25mm , male :0. 20 mm) is greater than that after ablation (female :0. 17mm , male :0. 15) . The reasons of lower growth rate and longer molting interval were discussed.

Abstract:When 50% of zygotes of Haliotis diversicolor aquatilis develop polar body . , with 6- DMAP as derivat ive , various concentration and dif ferent treatment time are used to induce triplo id by inhibiting releasing of the second polar body ò ; the experiment was carried out for productive seed breeding and culturing. Results show that when 6- DMAP is at the concentration of 300 Lmol#dm - 3 , and treatment time is 10min, the triploid rate of embryo is above 90%; In addition, embryonic hatching rate can reach as high as 85%, with larval deformity rate as low as 50%- 55% . After 7 months of cultivation, the rate of triploid of the culture abalone in test group is above 65%. On-the-spot acceptance check by experts proves that the average length of the shell of the culture abalone in test group grew 10% longer than that of control group. The average weight of the culture abalone in test group grew 30% weightier than that of the control group. Compared with diploid control group, triploid abalone displayed notable advantages in the growth of such aspect s as shell length and body weight ( t> t 0. 01( 58) ) .

Abstract:Hippocampus kuda Bleeker is an official oceanic fish in Chinese traditional medicine. Because of the great contradiction between supply and need , the nature resources of Hippocampus kuda Bleeker have declined sharply. The food consumption , growth and ecological conversion efficiency of H. kuda were studied in the Commercial Rearing Base Guangdong Richvast , the South China Sea , Guangdong Province. The Elliott2Persson model and Eggers model were used to determine its feeding periodicity , to quantify its food consumption quantity , consumption rate ,evacuation rate and food as well as energy conversion efficiency. The results indicated that seahorse (the range of body length 88. 5 -141. 3mm , body weight 5. 75 -13. 27g wet) fed in daytime with two peaks in 12 :00 and 18 :00 and were not fed in nighttime (the density is 200 ind·m 3 , DO is beyond 5. 5mg ·L -1 , BOD is below 3mg·L-1,pHis 7.5-8.2,transparencyis 50-85cm,salinityis 15.2-26.5). The mean daily food consumption of H. Kuda was 16. 634 2 ±0. 782 0g·(100g) 1 per day. The food consumption rate was 1 177. 25 cal ·ind -1 per day and evacuation rate was 0. 144 4g·(100g) -1 ·h -1. Its food and energy conversion efficiency was 20. 04 % and 31. 42 % respectively. The mean growth speed of its body length and daily growth rate was 1. 176 6mm per day and 1. 27 % respectively . The mean body weight growth speed of H. kuda and daily body weight growth rate were 0. 182 0g per day and 2. 27 % respectively. The food consumption of seahorse correlated with enviromental water temperature significantly ( P < 0. 01) . It can be expressed by the formula : FC =0.458 4+0.626 8 T ( P < 0. 01) . The relationship between the food consumption rate and its body weight as well as water temperatuer can be experssed better by the formula C =6.754 4 0.3014 T 0. 219 0 W ( F = 83. 596 3 F0.01 =18.00 F > F0.01)) .

Abstract:Two studies were conducted to reveal the ability of compensatory growth after food deprivation and refeeding in two sizes of red drum , Sciaenops ocellatus , weighing 8. 25 ±0.50 g and 40.41 ±2.45 g in temperature of 18 -20 ℃and 20-24 ℃respectively. Within the 30 days of experiment , both of the two results showed that each group had difference in growth, but the difference was not significant. Compared with control group , the water content and ash increased , while the lipid decreased and the protein did not significantly change in starved groups. After the starved fish were refed, their biochemical composition could reach the level of control group. As the starvation prolongs, feeding quantity reduced,but feed conversion efficiency increased. Meanwhile the oxygen consumption rate decreased and this trend stopped when the fish were refed , then the oxygen consumption rate gradually increased to the level of the control group. The results suggest that the mechanism of compensatory growth in red drum be due to the low oxygen consumption rate and high digestion and absorption after starvation.

Abstract:The experiment adopts oesophageal infusion with large dose DL2[42 3H ]2Phe to research protein synthesis metabolism in whole body , muscle and hepatopancreas of 20 ～30g grass carp in different essential amino acid (EAA) patterns. The results show that : 1. Four imbalance EAA patterns , respectively short of Lys 、 Met 、Trp 、Arg , compared with EAA pattern of muscle , result in remarkable fractional protein synthesis rate (FSR) decrease of muscle , hepatopancreas and whole body , which shows the decreasing by Met > Lys > Arg > Trp. 2.Followingthevariationof EAApattern, FSRof muscle, hepatopancreasandwholebodyhasasimilar change , and shows FSR by : hepatopancreas > whole body > muscle. 3. In Met ,Lys ,Arg and Trp four factors of EAA pattern , from Met to Trp have gradually and orderly weakened impact on protein synthesis in muscle and hepatopancreas of grass carp , in other words , Met has the largest impact .

Abstract:From June to July 2000, specimens of Meretrix meretrix Linnaeus which suffered from the 0red muscle disease0( RMD) were collected from Qinhuangdao district of Hebei province.The rickettsia-like organisms (RLO) were found and observed in the digestive diverticula. There are two types of RLO inclusion bodies, one is basophilia and another is acidophilia, both of which observed are circularity or olivary shapes. By the electron microscope, the epithelial cells were filled with RLO, of which the shapes and sizes are different. The infected cells w ith RLO presented a series obvious pathological changes. The endoplasmic ret iculum swollen and mostly turned into vesicles, the ribosomes degenerated. The mitochondria dissolved or condensed. The nucleus underwent a series of changes including the chromatin condensing, nuclear membrane swelling and forming nuclear vesicles. At last, the nucleus and most of cellular organelles disappeared. The RLO in binary f ission and budding in the cytoplasm were observed.

Abstract:Nutritional characteristics of Perna viridis EAP (enzymolytic animal protein ) were studied in this paper. The experimental results indicate that the content of crude protein is 72. 8 % (dry basis ) ,its nutritional value is as high as the level suggested by FAO/ WHO in 1973 as the amino acid score and the first limiting amino acid being 93 and sulfur2containing amino acid (Met and Cys ) , respectively. In addition, it is also rich in lysine,arginine,vitamin,mineral. Asitcontainssometastysubstancessuchasglutamicacid,asparticacid,and glycine in high content , it can be processed to an ideal seafood seasoning or healthy food. The findings in anti2 tumor test indicated that the inhibition rate on Sarcoma 180 was 50. 6 % when the dosage of Perna viridis EAP used was 320 mg·kg -1 , and the weight of spleen (immunity organ) in mice was increased obviously.

Abstract:BP neural network is a feed2forward neural network that is learned according to error backpropagation algorithm. BP neural network with excellent nonlinear approximation ability is widely applied to various fields. The excellent nonlinear approximation ability of BP neural network is ensured by determining the topology and structural parameters properly , learning efficient training data set with good typical characters , searching the global minimum solutions and escaping overlearning during learning. According to the recently research results of BP neural networks modelling , some aspects on comprehensive assessment of water environmental quality using BP neural networks were presented and studied in this paper. The main problems are too few of training set data , no verification ( validation ) set data , too large in network topology , which thus resulted in overfitting and overlearning in training and poor generalization of the neural networks model set up. The necessary modelling conditions for BP neural networks were concluded. The many BP models , presented before , for water environmental quality were set up under the conditions inconsistent with the necessary modelling conditions . The case study shown that the model set up under conditions disagreement with the necessary modelling conditions possessed poor generalization, prediction capability, and possibly induced multimodal in connection weights.