Abstract:Electron microscopy reveals mature spermatozoon of Tegillaca granosa. The observation shows that the spermatozoon of Tegillaca granosa is of flagellate construction in SEM. The body and head length of sperm is 52 - 58Lm and 2. 7- 2. 9Lm respectively. The mature spermatozoon consists of head, middle piece and tail in TEM. The acrosome is V-shaped in upside-down, and the top of V-shaped inflate to become a globoid in which there are many tiny particulate material. The unclear is egg-shaped with high electron-density. The vesicle was found in the unclear-region, and it is in different position. Two centrioles and f ive large globular mitochondras form middle piece of sperm. The centrioles are of cylindrical hollow construction surrounded by f ive mitochondras bodies and separated from the basal plate of the tail. A satellite body was found at the basal part of the distal centriole. The f lagellum is a typical / 9+ 20 microtubular structure limited by the cell membrane.

Abstract:The spermatozoon of Silurus soldatovi consists of head , middle piece and tail .The head is like a globe or an ellipsoid .There is no acrosome at the anterior end of the nuclears , whereas there is an implatation fossa at the posterior end of the nuclears , within which the chromatin is dense and nuclear vacuole(NV)is existent.The middle piece consists of the centrioles and the sleeve .Two single hemi-global centrioles are opposite to each other , thus constituting the proximal centriole , an empty globe , which is nucleus-dense .The distal centriole is like a bell , with its top connecting to the proximal centriole and with the entrance of its bottom connecting to the axoneme of the sperm tail .The sleeve , which is rich in mitochondria and vesicles , is connected to the posterior end of the nucleus .The main structure of the tail is axoneme ,which is the structure of a typical “9 +2” .There are no vesicles nor other cell organelles in the tail .The outer surface of the tail is quite smooth without fin-like structure .

Abstract:In Chinese mitten crab ( Eriocheir sinensis ) , the gonadal development of juvenile crab correlates with the total protein level in the hepatopancreas and hemolymph. The total protein level in the hepatopancreas of the juvenile crab is ( 121. 17 ? 44. 50) mg#g- 1 for female and ( 89. 43 ? 21. 86) mg#g- 1 for male respectively. But the protein level in the hepatopancreas of the precocious crab drops to ( 81. 08 ? 5. 84) mg#g - 1 for female and 70. 58 ? 9. 90mg#g- 1 for male respectively. Simultaneously, the rate between hepatopancreas and body weight of female juvenile crab is descending f rom 8. 18% to 3. 90% . The hemolymph total protein level of the female juvenile crab is ( 99. 55 ? 12. 06) mg#mL- 1, it is higher than that of the female precocious crab. The hemolymph total protein level of the male juvenile crab is similar to that of the male precocious crab. The total protein level in the hepatopancreas of the female adult crab is higher than that of the female precocious crab, but they have a approximate value of the total protein level in the hemolymph. The total protein level in the hemolymph and hepatopancreas is not different from the male adult crab and the male precocious crab.

Abstract:Based on monthly investigation data of beam trawl and hang trawl in the Pearl River estuarine waters in 1998, the paper analysed species composition, bio logical characteristics and seasonal variat ion of f ishes by principal components, regression, and hierarchical cluster analysises. The results indicated that fishes in the waters consisted of coastal or estuarine small species, among them, Collichthys lucidus, Johnius belengeri , Pampus argenteus, Trypauchen vagina, Odontamblyopus rubicundus , Oxyurichthys tentacularis , Chaeturichthys stigmatias, Parachaeturichthys polynema, Ambassis gymnocephalus , Cynoglossus bilineatus, Cynoglossus semilaevis, Coilia mystus, Umbrina russelli , Caranx kalla, Osteomugil ophuyseni , Harpodon nehereus , Trichiurus haumela, Trichiurus brevis , Euplerogrammus muticus , Ilisha elongata, Setipinna taty , Engraulis j aponicus, Stolephorus commersoni , Thrissa vitirostris , Gastrophysus spadiceus, Fugu xanthopterus , Loligo beka and Loligo duvaucelii are principal parts of f ishery resources. Seasonal variation in species composit ion was obvious, and benthic group differed f rom pelagic group in the time of succession.

Abstract:Based on biological data obtained from the specimens of Cynoglossus robustus from the East China Sea in 1994, the distribution, variant regularity and relationship with body character indexes of individual fecundity were studied. The results were summarized as follows: 1) The individual absolute fecundity r and relative fecundity r / L , r / W are all distributed normally. 2) Both the individual absolute fecundity r and relative fecundity r / L are linearly and directly correlat ive to the character indexes by weight . The relationships between the individual fecundity r , r / L and the length..s character indexes can be expressed in power functions, while the individual relative fecundity r / W has no significant relationship with these body character indexes except gonad weight and maturat ion coeff icient. 3) Younger than 4 years old , both r and r / L increase with age, but r / W shows no significant difference in various age groups. 4) Interrelations of two sets of variates, ( r , r/ L , r / W) and ( body length, body height, maturation coeff icient) , are developed by canonical correlations. They show that r is mainly dependent on the size of f ish and r / L depends on the body shape of fish.

Abstract:Triploid of Pacific oyster Crassostrea gigas Thunberg was induced by blocking pb2 w ith cytochalasin B ( CB) and 6- dimethylaminopurine ( 6- DMAP) and the triploid seed had been farmed with suspended longline in the sea. The egg was fertilized at 25 e and treated with 0. 5mg#L - 1 CB begun at 20- 30min pos-t fertilization lasted 18- 22min. Incubated density of zygote when treatment was about 4. 0- 4. 5 @ 107ind#L- 1. Triploid yield was 65. 2%- 70. 1% and velar larvae gain was 12. 3% - 14. 5%, and the eff iciency of triploid induction( ETI) was 0. 09. The concentration of 6- DMAP used to the induction of triploid was 400- 420 Lmol#L- 1 and the zygote density for treatment was 3. 0- 3. 5 @ 10 7 ind#L - 1 . Triploid yield was 58. 7% - 65. 4%, velar larvae gain was 52. 1% - 55. 4% , and ETI was 0. 32. The surrounding temperature when fert ilization, initial and lasting time for the triploid treatment were the same as those in CB. Spat harvest on the scallop shell which was as the collector was similar to both those in CB and 6- DMAP. The traits of the triploids induced by CB and 6- DMAP farmed for 14 months showed no significant difference in growth, meat harvest and condition index. Comprehensive comparison between the two methods showed that 6- DMAP was more applicable in triploid production than CB.

Abstract:Distribution and features of POC in cultivating waters of Sanggou bay was discussed , according to the nine investigations from Nov .1993 to Oct .1994 .Horizontal distribution or season change of POC was remarkable , but vertical distribution change was not apparent .There was a positive linear interrelation between POC and Chl-a .It was agreeable to the research results of other seawaters that larger POCB/POC value always appeared when photoplankton rate growing faster .The retention period of POC in euphonic zone was estimated to 29 days .

Abstract:612 bacterial strains from shrimp ponds and 10 freshwater strains which had been transplanted on the 2216E marine agar repeatedly were checked for their degrading abilities to the organic pollutants. 10 strains were selected by evaluating the growth on the shrimp-feed-medium, BOD in the liquid media and their extroenzymes activities. All these 10 strains were able to produce gelat inase, lipase ( Tween - 80) and 8 of these strains produced lecithinase, 9 produced amylase, 2 produced casinase, 1 produced alginase. All of them were able to degrade the feed of shrimp from 46. 5% to 59. 5% in two days and from 50. 8% to 72. 2% in five days. By the traditional physical and chemical methods, 3 of these strains were identified as Vibrio spp. , 3 as Pseudomonas spp. , 2 as Photobacterium spp. , 1 as Aeromonas spp. , and 1 as Bacillus subtilis.

Abstract:Contents of moisture, protein and lipid were analyzed in the muscle of mud eel fingerling ( weight: 9. 2- 15. 5g) , juvenile mud eel ( weight : 62. 3- 76. 0g) , small adult mud eel ( weight: 108. 3- 121. 4g) and big adult mud eel ( weight: 222. 8- 242. 8g) , and so was the composition of fatty acids, amino acids. The contents of protein ranged from 18. 79% to 19. 93% . The contents of lipid were fairly low. The fatty acids contained 19. 15% highunsaturated fatty acids( HUFA) . The essential amino acids accounted for 40. 98% of total amino acids. The content of glutamic acid was considerably high, reaching about 16. 95% of total amino acids.

Abstract:A universal primer PCR(UPPCR) , PCR-RFLP and PCR- SSCP had been screened for a molecular biological method that permitted the rapid identif ication of fish pathogens among them. The results showed that a universal primer PCR technology was available with specif ic primers from conserved regions of bacterial 16S ribosomal RNA genes. The bacteria tested included some common causative agents of f ish diseases such as Aeromonas hydrophila , Yersinia ruckeri , Vibrio anguillarum, Flexibacter columnaris, beta-Streptococcus, Pseudomonas f luorescens. The approach allowed the bacteria above and Escherichia coli and Bif idobacterium catenulatum detectable w ithout any alterations of the experiment condit ions. However, this study also found that the identification of species of bacteria tested depended on the combination of UPPCR and SSCP( PPCR-SSCP) , which was better than that of UPPCR and RFLP( UPPCR-RFLP) and made rapid diagno sis of fish disease pathogens possible.

Abstract:Under scanning electron microscope ( SEM ) , the surface microstructure on lymphocytes of Ctenopharyngodon idellus is characterized with full of bumpiness and holes, or rather smooth or protruding with small cones, whereas the surface microstructure on lymphocytes and thymocytes of Trionyx sinensis is characterized w ith full of bumpiness and holes, or rather smooth. The lymphocytes and thymocytes f illed with bumpiness and holes are evidently more than others. Under optic and scanning electron microscope, the rosette format ion of lymphocyte of C. idellus with SRBC is not obvious, whereas rosette forming percents in lymphocytes and thymocytes of T. sinensis are respectively 25% - 34% and 36%- 47% . The lymphocytes and thymocytes which form rosettes w ith SRBC are predominantly ones f illed with bumpiness and holes ( similar to T lymphocyte of mammalian) . The immuno-l histochemistry on the cross-reactivity by using monoclonal antibody against human CD2 shows that the CD2-positive percent of lymphocytes in peripheral blood and thymocytes of T. sinensis are respect ively 24% and 33% , but no cross-react ivity is found on lymphocytes in peripheral blood of C . idellus.

Abstract:Volatile compounds collected into Tenax TA from fresh uncooked crucian carp ( Carassins auratus ) were analyzed by GC-sniffing and identif ied by GC-MS. The experimental result showed that the specif ic grassy and earthy odor of f ish was correlated with the following C5- C8 carbonyls and alcohols: 1-penten-3-one, 2, 3- petanedione, 1-penten-3-o l, hexanal, ( E, Z)-2, 4-heptadienal, 1-octen-3-ol, 1, 5-octadien-3-ol et al. Among these compounds, hexanal was found to make the most important contribution to the odor of crucian carp. On the other hand, the activity of a lipoxygenase-like enzyme was found in the skin and gill of crucian carp. The crude skin enzyme exhibited act ivity on arachidonic acid, resulting in three C8 compounds.

Abstract:DNA single strand breaks in the liver of Boleophthalmus pectinirostris with benzo ( a) pyrene exposure were detected using DNA alkaline unwinding assay under experimental ecological conditions. It turned out that DNA single strand breaks were effected by exposure time and exposure concentration and were time-dependent and dose-related. The repair of DNA damage was weak because no significant change was observed after the f ishes were transferred to clean sea water. All of the results show that DNA single strand breaks are suitable to be the bioindicator of DNA damage with BaP exposure.

Abstract:Based on the monthly length-frequency data obtained from the northern area of East China Sea during the periods of 1986 - 1987 and 1993 - 1995, the population dynamics and maximum sustaining yield of Parapenaeopsis hardwickii were studied. The dominant length group for the female was 70- 90mm, which was 63% of the total female. By using ELEFAN.and òtechnique, the growth parameters were estimated: K= 1. 7, L ] = 128mm and t0= - 0. 1185, the approximate longevity was 1. 3234 years. Total mortality z= 8. 3280 , and mean selection length Lc = 59. 67mm. Natural mortality M = 2. 7427 was est imated by using the empirical relationship between M, the growth parameters and mean environmental temperature, and the exploitation rate, E = F/ Z = 0. 6706, was obtained. Yield-per-recruit and the value of yield-per-recruit analysis indicated that the stock of Parapenaeopsis hardwickii had been fully exploited. An increase in yield-per-recruit and the value of yield-per-recruit may be expected if the size of first capture has a moderate increase. The value of yield-perrecruit would be reduced with the increase of f ishing mortality.

Abstract:There is some selective water temperature range in f ishes. Fishes keep up the same direction with water temperature variety in temperature selection.The seletive temperature of warm species tends to higher temperature than that of temperate species. If temperature goes up faster or temparature of fish adapted was lower, selective temperature of these f ishes tend to lower. Seletive temperature of main species fished is 1- 3 e higher than the median temperature of that month, 1 - 2 e higher in the majority of species. Variable range of selective temperature in main species is mainly 2- 6 e , 3- 5 e . Selective temperature in main species f ished is 20- 24 e in winter and spring , 26- 29 e in summer and autumn.

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