Abstract:Crosses between and within two different geographic stocks from Japan and China of Farrer.. s scallop, Chlamys f arreri , were produced, hybrids of reciprocal crosses derived from Chinese population ( C) .. .. Japanese population ( J) .. and Japanese population ( J) .. .. Chinese population ( C ) .. respect ively. Of fspring were measured at 10 months old each group for the research on the growth characteristics and survival. The results indicated that there existed signif icant heterosis ( or hybrid vigor) for growth of shell height, shell length, shell w idth and live weight and survival and young scallops f rom the reciprocal cross had a higher survival and growth than two pure populations, and that there were stronger heterosis in F1.. hybrids than in F1 hybrids. There was a signif icant difference in shell width and survival, but no signif icant difference in other characters between Chinese population and Japanese population. The results of experiment testif ied that hybridization is an important tool to increase the performance and fastness ( survival) of scallops.

Abstract:A big group of transgenic Cyprinus carpio w ith salmon growth hormone gene was constructed. A .. super fish.. with very faster growth rate was selected from more than 10 000 transgenic common carps. The results of four years sequential growth experiments of the .. super f ish.. and its controls were reported. The result of three years sequential growth experiments of the progenies of the .. super fish.. was reported, and the data of the weight of those progenies and their controls were also reported here. The statistical analysis of those data showed that the effect of salmon growth hormone gene for the transgenic common carp was positive, but only a few in tho se transgenic f ish with this faster growth effect. The weight of the .. super.. f ish was about two times the weight of the biggest f ish in control. The faster growth effect could be transmitted to next generation, and the ratio of faster growth fish in progenies was much higher than that in transgenic Cyprinus carpio population. 43% progenies had foreign genes, but only 14% progenies had the fast growth feature and kept this fast growth trait in their three year old. Some progenies was 5 kg at three year old. In the paper, the future of transgenic f ish was also discussed. Gene transfer is a very powerful tool for scientists to create new aquaculture species with good trait , although this technique needs to be developed further. Gene transfer methods w ill benef it f rom other basic researches such as genome research and molecular biology technology. Transgenic f ish would be used in farm af ter it is tested to be no harm to ecosystem and human beings. For this, more researches on ecosystem testing should be done from now on.

Abstract:The histological structure of digestive tract of Pseudosciaena crocea was studied using light and electronic microscopy. The epithelium of lingual mucosa was multi..layered epithelium and contained mucus.. secreting cells and taste buds. There were serous alveolis in menbrana propria of lingual ventral region. The oesophagus covered a multi..layered epithelium and the mucous cells under the squamous cells. The stomach mucosa epithelium formed with a single..layered columnar epithelium, a great deal number mature mucinogen granules were present in the free edge of the cells, and immature stages mucinogen granules in the around near nucleus of the cell, and the cell organs were present in circumambient and under the nucleus. There were mucous glands in the cardiac and fundic portion, and the stomach glands were present in the membrana propria enormously, and absent in the pylorus. The stomach cell shape was short taper, typical oxynticopeptic cell, in which there were tubulovesicular systems and pepsinogenic granules. The fore, mid.. and hind.. intestine epithelium was single..layered columnar epithelium, and there were a lot of mucus..secreting cells and dense microvillus in the epithelium, and the connecting complex was present in lateral edge, and abundant cell organs in the cells. The results showed that there were close correlation between the characterist ic of histology structure of digest ive tract and digestion and absorption of Pseudosciaena crocea.

Abstract:The male reproductive system of Oratosquilla kempi includes: testis, vas deferens, penis, and accessory sex gland. The duct..shaped testis, with a straight end, curves forward gradually and finally curls into a ear..like structure at the seventh and eighth thoraxmeron. The wall of vas deferens has no muscles. There is a stick..like penis at the base of the eighth thoraxmeron, and the join point, like a membrane, is soft enough to curve freely , but the free end is relatively hard with crust around. Between the fourth and seventh thoraxmeron, a pair of male accessory sex glands could be seen, like thin silk, and lef t and right ends reach penis paralleled by the same side vas deferens respectively. The testis cavity.. s tip is f illed with spermatid of different developmental stages which are gradually maturing from the tip to post.., mid.., and front..end testis, then to vas deferens and penis. The spermatid is egg.. shaped with thick membrance but without flagellum and acrosome, and its size is about 8. 5..m .. 7. 0..m.

Abstract:Biochemical composition of male reproductive system and hepatopancreas, w ith special reference to lactate dehydrogenase( LDH) activity, was determined in the Chinese mitten-handed crab, Eriocheir sinensis . The results reveal that the glandula accessoria and luminal contents( seminal plasma along with spermatophores) are rich in carbohydrates ( 33. 456mg .. g - 1 and 21. 537mg .. g - 1 of wet t issue weight, respectively ) . The carbohydrate contents of hepatopancreas and spermatophore and testis are low . Luminal contents and hepatopancreas contain the highest level of gluco se and glycogen respectively, but spermatophore contains very low level of gluco se and in testis and hepatopancreas glycogen is too low to be detected. Protein content of hepatopancreas is higher than that of other tissues. Hepatopancreas and testis contain the higher level of lipid. Triglyceride exists in the hepatopancreas and testis only and the content of hepatopancreas is higher than that of testis. LDH activity is very high in seminal vesicle, and probably this is due to the storage of seminal substances within this region. On the contrary, spermatophores show only moderate amount and a low LDH activity detected in the seminal plasma may be due to it s leakage f rom the spermatophores. Compared with reproductive system, LDH activity of hepatopancreas is significantly low. All results show that the pattern of sperm metabolism in Eriocheir sinensis is anaerobic by utilizing carbohydrates. A high carbohydrate content of glandula accessoria suggests that spermatozoa may rely on carbohydrate reserves of seminal vesicle for its survival in the spermatheca.

Abstract:The radula of nine cephalopods are compared on the basis of scanning electron microscopic observation and morphological measurements .Results indicate that all of them consist of 7 longitudinal rows of teeth :a median tooth and the 1st , 2nd , and 3rd lateral or lateral , inner marginal , and outer marginal teeth .The formula of radula is 3·1·3 .Sepioidea (Sepia robsoni , S .esculenta , S .pharaonis , S .latimanus , S .aculeata , Sepiella maindroni , Euprymna berryi)has only one cusp in the median tooth , and a marginal plate is absent .The median tooth has 3 and/or 5 cusps and marginal plates are found in the two species of Octopus ocellatus and O .variabilis .Other differences in the radula structure among the nine species are illustrated in detail .The relationships of radula of the cuttlefishes , octopuses and squids are discussed .It is suggested that radula should be thought in the cuttlefish taxonomy .

Abstract:An indoor static system was employed in this experiment to measure the energy budget of Ruditapes philippinarum at temperature of 3 .. , 5 .. , 8 .. and the effect of tissue weight on the oxygen consumption rate (OCR) and ammonia excretion rate ( AER) . The result showed that the OCR and AER had the negative correlation with the t issue weight. The temperature had positive inf luence on the ingestion rate and growth rate (K1 and K2 ) of clam. Temperature had great effect on the rat io of energy. The temperature had positive influence on the energy ratio of growth, had negat ive influence on that of respiration and ejection. At the equat ions of the energy budget of clam, the ratio of growth, respiration , ejection and excretion comprised 6. 13% - 34. 63%, 23. 37%- 32. 73% , 41. 131% - 60. 69%, < 3% respect ively of the total energy.

Abstract:Based on the investigation on the fluctuation of the catch and catch per unit effort ( CPUE) in Zhoushan Fishing Ground during the period from 1952 to 2001, it is showed that the catch and CPUE can be illustrated by determinacy tendency and stationary random sequence. Combining the determinacy tendency models w ith ARMA( p q) models, the complex models were built to describe the dynamics of f isheries resources. The stages of the f isheries resources f luctuation were divided. The utilization extent of f isheries resources was discussed and the f isheries managing measures were propounded.

Abstract:For the seven representative populations of soft2shelled turtle ( Trionyx sinensis ) in China , an experiment in aquaculture performance from larvae to adult stage , was carried out in green2house with constant temperature (30 ℃) and lasted over 300d by randomized block design. The major results were : (1) There was a highlysignificant differenceindailyindividual bodyweight gainamong 7populations ( F > 0. 01) , and the order was Yellow River population > Huai River population > Poyang Lake population≈ Dongting Lake population > Taiwan population > Chongming population > Taihu Lake population. The Yellow River population was higher than others significantly ( t > 0. 01) . (2) The daily average yield per square meter among 7 populations was highly significant ( F > 0. 01) , the order was Yellow River population > Huai River population > Dongting Lake population ≈ Poyang Lake population > Taiwan population > Taihu Lake > Chongming population , and Yellow River population was also higher than the other populations significantly ( t > 0. 01) . (3) The individual variation of growth rate was remarkable either within a population , or among popualtions , and the ratio of maximum body weight / minimum body weight was the lowest in the Yellow River turtle , e . g . 5 . 6 ( ♀) ～8. 3( ♂), andhighestinthe Chongmingturtle, e.g. ,17.1( ♀) ～17. 7( ♂) . The coefficient of variation of body weight was lowest in Yellow River turtle. (4) In general , the sex ratio of 7 populations was 50. 7 % ( ♀) : 49.3%( ♂), maleturtles growfasterthanfemale ones by 8.4%( t > 0. 01) .

Abstract:From January 1998 to July 2000, detailed observation were made on the growth of blood clam, Tegillarca granosa, in the pond culture of Leqing Bay ( Zhejiang Province, China) . Larva ( just hatched) is 92 - 100..m in shell length, after 10 days cult ivation, it attains 180. 5- 201. 5 ..m in shell length, average increase of 8. 9- 10. 2 ..m per day. After attachment , juveniles increase to 634. 1 ..m in shell length from 191. 3 ..m, average increase of 27. 7..m per day. Juveniles at mid culture in pond, average shell length achieves 8. 34mm in 9 months, this is the commodity seeding, average increase 0. 86mm per month. After 15 month rearing, it becomes the finished product , average shell length 28. 57mm, average increase 1. 35mm per month. Tegillarca granosa belongs to slow growth type. Several growth indexes of the blood clam larvae and seeding in cultural ponds, juveniles at mid culture, and mature blood clam were measured and weighed. The following regression equations, which have closely correlation were obtained: (1) Linear regression equation of shell height(H ) and length( L) of blood clam larvae: L = 58. 547+ 0. 859H (2) Linear regression equation of shell height(H ) and length( L) of blood clam seeding: L= 128. 643 1. 795H (3) Linear regression equation of shell height(H ) and length( L) of blood clam juveniles: L= 1. 517H - 0. 368 (4) Linear regression equation of shell height(H ) and length( L) of mature blood clam: L = 1. 660H - 9. 563 (5) Linear regression equation of shell width ( D) and length( L ) of mature blood clam: L= 1. 349 1. 425D (6) Functional equation of body weight ( W) and length ( L) of mature blood clam: W= 0. 831L 3. 425

Abstract:Allogynogemetic crucian carp ( average initial weight , 4. 2 .. 0. 3g ) were fed with basal diet supplemented 0. 1%, 0. 2%, 0. 4% Bacillus sp. , 0. 3%, 0. 6% , 1. 2% selenoyeast, complex of 0. 2% B . sp. and 0. 3%, 0. 6% , 1. 2% selenoyeast respectively for two months. Control group was fed with basal diet. Triplicate groups were made for each diet . The act ivit ies of protease and amylase in the intestine and hepatopancreas were determined. The activities of protease in the intestine and hepatopancreas fed with dietary 0. 2% B. sp. were 466. 2% and 85. 4% higher respectively than those of the control group. The activities of amylase in the intestine and hepatopancreas fed with dietary 0. 1% B . sp. were 83. 7% and 129. 5% higher respectively than those of the control group. The act ivit ies of protease in the intestine w ith three levels of selenoyeast were similar to those of the control group. The activity of protease in the hepatopancreas with dietary 0. 6% selenoyeast was 43. 7% higher than that of the control group, the act ivit ies of amylase in the intestine and hepatopancreas with dietary 0. 3% selenoyeast increased by 84. 2% and 163. 9% respectively. The activities of protease and amylase in the intestine fed with dietary 0. 2% B . sp. and 0. 3% selenoyeast complex were 395. 5% and 95. 4% higher respectively than those of the control group, while the activities of protease and amylase in the hepatopancreas fed with dietary 0. 2% B . sp. and three levels of selenoyeast were not remarkably higher than those of the control group. Compared to dietary 0. 2% B . sp. group, the activities of protease in the intestine and hepatopancreas fed w ith dietary 0. 2% B. sp. and three levels of selenoyeast complex decreased drastically w ith the increasement of the level of dietary selenoyeast, while there were no remarkable difference in the activities of amylase between two groups. Compared to dietary selenoyeast group, the activities of protease and amylase in the intestine and hepatopancreas fed with dietary selenoyeast and 0. 2% B . sp. complex were not changed remarkably.

Abstract:To develop a nested..polymerase chain reaction ( nested..PCR ) for detect ion of Renibacterium salmoninarum, the causat ive agent of bacterial kidney disease, 2 pairs of primers, BKDF and BDKR, BKDR2 and BKDF2, were designed for amplif ication of 501 bp and 314 bp DNA fragments of the sequence coding the 57 kDa cell surface protein of R . salmoninarum respectively. No specif ic f ragments were amplif ied when other principal f ish bacterial pathogens were used as templates in PCR and nested..PCR tests. The sensit ivity of PCR was limited to 1. 8 .. 10 3 CFU..mL - 1 when the bacterial DNA was extracted by phenol..chloroform..isopentanol or boiling &f reezing..thawing method. The sensitivity of nested..PCR was 100 times higher than that of PCR test. The mixture of bacteria and cod eggs was detected using nested..PCR and the results showed that the nested..PCR was an effective and reliable method for the detection of R . salmoninarum.

Abstract:This paper reports the histopathology of Meretrix meretrix Linnaeus parasitized by the larvae of Bucephalidae. The specimens were collected from mollusca-farming ponds in Laizhou, Shandong province in March, 2001. The main symptoms of infected clams is that the visceral mass becomes thin, the adductor muscle is weak and the surface of the shell lacks luster. Histological examination revealed that most of the larvae occupied the genital gland of the clam, with relatively few in other organs. It damages not only the tissues parasitized by the parasites, but also caused the debilitation of other organs. In heavy infestations, the gonads is completely destroyed and replaced by mass of larval digeneans. Other organs exhibited obvious pathological changes, e. g. the epithelial cells detached from the wall of digestive tract, digestive diverticula and gills. The structure of muscular tissues becomes irregularly arranged, with some tissue melted. In the end, all of the essential organs were broken down, which causes the host dead.

Abstract:The paper summarized the progresses and achievements of the studies on the gynogenesis of the marine mollusks at home and abroad in recent years,and pointed out the study direction on gynogenetic shellfishes and 6-DMAP used as an ideal medicine for raising the induced rate of marine shellfish gynogenesis.

Abstract:Genetic homogeneity between Pengze crucian carp and strain A of silver crucian carp was studied by using transferrin,isozyme and RAPD markers.The studied individuals of Pengze crucian carp showed transferring patterns were the same of silver crucian carp A strain while distinct from those of other crucian carp populations.As far as isozyme is concerned,the MDH,LDH and EST are all of the same with only slight differences in SOD between them.The RPAD patterns clearly indicated high homogeneity among 16 individuals (6 sampled from individuals of two years old and the others aged one) from crucian carp of Pengze and 5 individuals from strain A of silver crucain carp.Nearly indentical banding patterns were observed among all individuals.Average genetic distance within all the individuals is only 0.011,suggesting crucian carp of Pengze might possess indentical genetic background with strain A of silver crucian carp.

Abstract:Free-living Porphyra haitanensis conchocelis was cultured under continual light,then it was treated with Van,DIDS and SITS,the inhibitors of inorganic carbon utilization,to study the mechanism of inorganic carbon utilization in the conchocelis.The results indicate that Van inhibits the utilization of inorganic carbon most,with a rate of 71.3%,and the rates of DIDS and SITS are relatively lower,42% and 35.5% respectively.The inhibition rate of Az is 25.3%,which indicates the external CA is not an important part of its inorganic carbon uptake.A complementary conclusion is that the main part of inorganic carbon absorption in P.haitanensis conchocelis is through active transport of HCO3^- and CO2.