Abstract:The result of scanning electron microscopical examination of the gill of Clarias fuscus is described .The various features of surface structures of the filament-like gill , lamelliform gill and branched gill have been compared and studied .The relationship of the three kinds of gill were discussed .

Abstract:The fertilzed eggs of Tegillarca granosa stained with DAPI were observed by f iuorescent microscope. The result show s that the mature eggs were at metaphase of first meiosis. After sperm penetrating, the eggs released their first and second po lar bodies and f inished their meiotic division. Some first polar bodies divided into two small cells. The eggs Tegillarca granosa became monospermic. While the male and the female pronucleus were produced, they expanded to their maximal size. And the male pronucleus moved to the female pronucleus during the period of associating of the two pronucleus.

Abstract:Structure and function of the androgenic gland in Chinese mitten-handed crab, Eriocheir sinensis, were studied w ith tissue section, histochemistry , electron microscope and culture in vitro techniques from April 1996 to March 1997. A pair of androgenic glands were located on the surface of the subterminal portion of the ejaculatory duct near the base of penis. The cords of the gland tissue consisted of many gland alveoluses. The structure of the gland changed great ly with the testis development cycle. The developmental cytology of the gland cells can be distinct ly devided into three stages: proliferation phase, synthesis phase and secretion phase. The gland secreted in a holocrine fashion. The androgenic gland hormone is composed primarily of protein and lipid as indicated by positive reaction to Ninhydrin- Schiff and phosphomolybdic acid. Spermatogenesis can be accelerated and oocyte development can be inhibited by the androgenic glands when cultured in vitro.

Abstract:The lipid accumulations during the stages of the ovarian fast maturation( from September to December) and their ef fect on the spawning of Eriocheir sinensis were studied. The results shown that gonadosomic index ( GSI ) and lipid content were significantly increased, both neutral lipids ( PL ) ( mainly triacylglycerol and cholesterol) and phospholipid( PL) ( mainly phosphatidylethanmine) were responsible for the increase in ovarian lipid, and NL increasing from 1 3. 67% to 20. 12% ovary dry weight , PL f rom 7 . 21% to 10. 70% ovary dry weight . The ratio of NL/ TL or of PL/ TL remained relatively constant during the fast ovarian development , and NL concentration of ovary were always higher than that of PL. The fatty acid composition of lipids, PL and NL of ovaries varied markedly during this development stage. There was much more long-chain polyunsaturated fatty acids such as C20B5 and C22B6in the mature ovary than those at the start of fast development of immature ovary ( NL P < 0. 05; PL P < 0. 01) , but the percentage of C20B4 decreased signif icantly ( P< 0. 01) during this stage. It was also found the mature crab that could not spawn was partly because of their lower PL content( %ovarian dry wt ) and lower percentage of the C20B5 and C22B6 in PL than that of normal mature ovaries in Dec. The results suggest that the lipid, manily phospholipid and long-chain polyunsaturated fatty acids such as C20B5and C22B6 are essential for ovarian fast development and must be obtained from dietary source.

Abstract:Effect of environmental factors on the activation of spermatozoa of Chinese ocellated sleeper, Bostrichthys sinensis ( Lac.p .de) , was studied. The optimum activat ing salinity for the spermatozoa was 5- 15. The activation of the spermatozoa concerned with not only osmosis or salinity, but also with composition of solution. The function of K+ was represented as a restraining factor to activation and movement of the spermatozoa in the present condition. The spermatozoa had a strong adaptability to the variation of pH, and the activating rates were more than 70% while pH of the activating solution varied from 5. 5 to 9. 5. The optimum pH of the activating solution was neutral or weak acidity for the spermatozoa, the swimming time of the spermatozoa was the longest when pH was 6. 0. The spermatozoa of Chinese ocellated sleeper were cryopreserved successfully by using a simple procedure . Sea water with salinity 40 or a solution containing 1. 5% NaCl , 1 . 5% KCl , 0. 25% CaCl2 and 0. 25% MgCl2, was practical extender for cryopreservation of Chinese ocellated sleeper spermatozoa. DMSO was an effective cryoprotectant, and its optimum concentration was 10% in this study. The activation rates of the pos-t thaw spermatozoa were almost as good as the control. s , namely fresh spermatozoa, and their fertilizat ion rates were over 80%, approaching the control. s.

Abstract:The testes and ovarian development and maturation were achieved by combinative injection of carp pituitary extraction( CPE) and human chorionic gonadotropin ( HCG) for 5- 6 times in male and 9- 10 times in female Japanese eel ( Anguilla japonica ) . The mGnRH contents in the telencephalon, disencephalon, mesencephalon and hypothalamus signif icant ly increased after injection of CPE + HCG in male and female Japanese eel, but contents in the metencephalon and myelencephalon did not change. Injection of CPE HCG also increased the cGnRH- ò contents in the metencephalon and myelencephalon in male Japanese eel, but had no effect in the female. The serum GtH levels in male and female Japanese eel increased dramatically 1 day after each injection of CPE HCG, then gradually decreased 10 days after. However the serum GtH levels in female Japanese eel remained significantly higher than the corresponding control in 10 days after 7 inject ions. The serum testosterone concentration increased after injection of CPE HCG and kept on a high level in female Japanese eel, but did not change during the time of 1- 4 injection in male Japanese eel. The serum 17B- estradiol contents were not dif ferent with the corresponding controls during 4- 6 injections in female Japanese eel, but increased after 7 injections.

Abstract:Allozyme variation within three natural populat ions of Crassostrea plicatula from Shandong coastal waters ( LZ, LD and QD ) and one cultured population of C. gigas from Rongcheng ( TP) were investigated by horizontal starch gel electrophoresis. 20 loci were detected in 9 enzymes. The percentages of polymorphic loci were 60% in LZ and QD populations and 55% in the other two. High variation was shown in LZ and QD populations. Mean heterozygosity observed in LZ, LD, TP and QD was 0. 216 ? 0. 050, 0. 165 ? 0. 036, 0. 139 ? 0. 034 and 0. 195 ? 0. 042 respect ively. Mean effect ive number of alleles varied from 1. 207 ? 0. 086 to 1. 422 ? 0. 165. More genetic variations were shown in LZ and QD populations than in LD and TP populations. Heterozygous deficiency was common in all populations. Nei distance between TP and the other three populations of C. plicatula were very similar to each other, but the largest one still below that of LZ and QD ( 0. 0500) . The smallest Nei distance was between LD and TP populations( 0. 0099) . The research indicated that C. plicatulaand C. gigas might belong to the same species of C. gigas .

Abstract:According to the data of 979. 48 million Penaeus orientalis seedlings released in Dongwuyang Bay( an inlet with narrow mouth, situated in eastern part of Fujian Province) from 1986 to 1995, this paper has studied the releasing technique and the enhancement effect of post larvae. It could be concluded that the suitable releasing time is from the last ten days of April to the f irst ten days of May in every year, the suitable water temperature is f rom 16 e to 20 e , the releasing region is from Hanjiang to Hongjiang and the optimum opening date is mid July. The results also showed that if we have a good grasp of the releasing technique, strengthen the management of the region, release the post larvae of no middle culture and get average body length over 10 mm, the annual average recapture rate can be increased up to 5. 26% and the enhancement effect is very remarkable.

Abstract:In this paper, the efficiencies of dif ferent culture systems in Sishiliwan Bay, Yantai, China, were comparat ively sem-i in situ studied from April 5, 1998 to June 23, 1998. In the experiment , one control and nine culture systems, established ( 5 m @ 2 m @ 1 m in volume) near the bay, in which Chlamys farreri , Laminaria japonica , Apostichopus japonicus w ith dif ferent densities were stocked. Water exchanging quantity was 100% per day in each system. The results show that the productivities of C . f arreri in monoculture system and in polyculture system of shellf ish, seaweed and sea cucumber are 0. 56g / m2#d and 0. 78g/ m2#d respectively , and that of A . japonicus in polyculture system is 74. 7 g/ m2. The growth rate of C. farreri in monoculture system was slower than that in two kinds of polyculture systems. The eff iciency of shellfish, seaweed and sea cucumber polyculture system is better than that of shellf ish monoculture and shellf ish and seaweed polyculture systems. The optimal scallop stocking densities in monoculture system, and polyculture system of shellfish, seaweed and sea cucumber are 21. 0 and 23. 0 ind/ m 2 respectively , and the optimal densities for kelp in polyculture system of shellfish and seaweed, and in the mixed system of shellfish, seaweed, and sea cucumber are 0. 68 ind/ m 2 and 0. 71 ind/ m 2 respectively, and that of sea cucumber in polyculture system of shellfish, seaweed and sea cucumber is 2. 0 ind/ m2.

Abstract:The computer pattern recognition ( CPR ) technology is applied to the study on the relationships among dissolved oxygen ( DO) concentration and nine ecosystem factors in the Siniperca chuatsi ponds. The factors differ greatly in distinct ponds or periods . In high-dimensional space, it is clear and successful that two kinds of samples, high and low DO, gather themselves in different regions. It indicates markedly regular relationships between DO and ecosystem factors. The nine superiority ecosystem targets for maintain high DO are sought by CPR favorable technology. In water, DO and nine ecosystem factors follow polybasic quadratic function relation, R= 0. 97. Using the mathematical model prediction DO , precision is 9 3. 9% , predicting the DO is over 8. 4 mg/ L for favorable ecosystem factor.

Abstract:Gymnolinium sp .red tide occurred in May 17 to June 6 , 1998 in Fujian coastal waters .This red tide caused heavy losses to abalone aquaculture .Preliminary concluding :Basic reason of causing abalone death was that Gymnolinium sp .et al had produced some toxins .We studied removal means of red tide organisms in abalone aquaculture on land , the most important countermeasures were listed below:① 5 ～ 20mL/m3 concentrations of Formaldin could kill Gymnolinium sp ., but could not disintegrate them;②0 .1 ～ 0 .5 g/m3 concentrations KMnO4 could control the disaster caused by Gymnolinium sp ..

Abstract:It was demonstrated that soft..shelled turt le, Trionyx sinensis, with bacterin T3 had anamnest ic response that was situated between the f ish and mammal. It possessed these characters: ( 1) the anamnestic and primary response differed significantly in peak stage of IAT of soft..shelled turtle, and its ratio reached two or so; ( 2) antibody of primary response produced quickly , which got to the highest level on about the 16th day after the second immunization, but its disappearing speed was slower than producing one; ( 3) the producing rate of IAT of anamnestic response went up faster than that of the primary, but the dropping rate was slower.

Abstract:White spot syndrome virus(WSSV) , a non-occluded virus which is the causat ive agent of a disease caused high shrimp mortalities and severe damage to shrimp cultures, was iso lated and purified. Virions are rod-shaped, enveloped, 430nm @ 120nm in size, with a tai-l like appendage at one extremity. Nucleocapsids are 300nm @ 85nm in size, and are composed of rings of subunits in a stacked series. The genome of the virus is a double-stranded DNA molecule. The full length of the DNA is estimated to be longer than 165kb. EcoR . or Sal . restriction fragents obtained after agarose gel electrophoreses were cloned in the system pBluescript ò KS-XL1-blue. Southern hybridization, dot blot hybridization and in situ hybridizat ion were performed using the WSSV EcoR . clone fragments as probe, and those proved that these clone fragments are specific to WSSV. According to the results of nucleotide sequence analysis, none of the WSSV clones showed considerable se- quence homology with those of other known viruses or organisms, indicating that WSSV may only be distantly related to baculoviruses.

Abstract:Inactivated whole -cell and cell chemical components were prepared with Aeromonas hydrophila Ah961004 ,Ah960916 ,Ah970516 and A .sobria As970510 ,Soft shell turtles , Trinyx sinensis ,were immunized via intramuscular route , after 15d booster doses , challenged with strain Ah961004 intraperitoneally and observed for 20d , The results showed that the group of A .sobria As970510 inactivated whole -cell with its extracellular products and the group of A .hydrophila Ah961004 outer membrane components had highly protection against strain Ah961004 , with the protection rate 87 .5 % and 75 % respectively , the other groups were lower than 50 %.

Abstract:The virus nucleic acid was isolated from disease Siniperca chuatsi , and extracted with RNase, DNase and Mung bean nuclease respectively. The tests indicated that the virus genome is dsDNA. Part of the genome of Siniperca chuatsi virus were successful amplif ied by random primer ( contained the enzyme position of EcoR .. ) . The PCR products were recovered from low melting-temperature agarose and cloned in pUC19 plasmid. Three kinds of recombinant plasmids have been identified with EcoR ... Two kinds of it have been sequenced. There were 369bp and 450bp in size. It was demonstrated that there were not homology sequences against tho se in GenBank.

Abstract:In this report, pho spholipids in six shellf ishes ( Mytilus edulis, Chlamys f arreri , Crassostrea plicatula, Philippinarum Ruditapes , Sinonovacula constricta and Scapharca subcrenata ) were studied in a comparat ive way. Offering meat rate, total lipid, neutral lipid, polar lipid, phospho lipids, composition of phospholipids and fatty acid of six shellfishes were tested. The experimental results were as follows: the characteristic of phospholipids in six shellfishes had definite dif ference . The content of PI in Oyster was particularly higher. CL was only detected in Oyster and Blood clam. Only EPA but no DHA was found in Blood clam. The common characteristic of six shellfishes was that PC and PE were seventy percent of the content of phospholipids.

Abstract:Nutrients and composition of free amino acids in edible part of pearl oyster, Pinctada martenssi , were studied in this paper. The content of crude protein is 74. 9% ( dry basis) . The edible protein is rich in tasty amino acids such as 2. 21% glutamic acid, 1. 45% aspartic acid and 1. 01% glycine. The protein nutrient value is high because of the score of amino acid being 82 and the first limiting amino acid being sulfurcontaining amino acid ( Met and Cys) as compared with the FAO/WHO suggested level ( 1973) . Taurine is as high as 1. 38% , which account s for 74% of the total free amino acid. The edible part of pearl oyster is rich in minerals, especially microelement s Zn and Se.

Abstract: