Abstract:China carps have culturally long history and economically important values. Its annual yield is far more than those of other fishes. Recent decades, many innovate breeds have been exploited successfully, greatly increasing production and improving attribute. Cyprinis carpio var. xingguonensis , Cyprinis carpio var. wuyuanensis , Cyprinis carpio var. wananensis , called Three Kinds of Red Carp in Jiangxi Province , along with Cyprinus carpio haematopterus and Cyprinusy carpio var. are typical cultural varieties and wild species in China , which play a prominent role in fish genetic breeding. The second molecular markers , called microsatellite markers about 84 were applied to detect genomic DNAs for the fishes above mentioned. As a result , there are 43 pairs of primers that can amplify clear bands when the annealing temperature risen to 60 ℃, of which 14 markers display polymorphisms between populations, which possess 2 -4 allelic sites. Further, microsatellite loci MFW4, MFW19 , MFW23 and MFW26 express individual polymorphisms within populations , which have 7 -13 allelic sites. The data collected indicate that there is slight difference in three kinds of red carp in Jiangxi province , of which Cyprinis carpio var. xingguonensis and Cyprinis carpio var. wuyuanensis are closer in genetic relationship (0. 93 ). Again, there is a higher genetic similarity between Cyprinusy carpio var. and Cyprinus carpio haematopterus (0. 89), demonstrating that they belong to the same sub2species. According to these results obtained from microsatellite markers , genetic diversity of 5 carps is discussed.

Abstract:The process of ovarian development in artificially2bred Amur sturgeon (1 -8 years old) was investigated histologically. It shows that in fish one year old , ovarian was made up of a lot of oogonium clusters and two or three years old , germ cells of phase I ovarium was primary gonocyte stage (10 -60μm) or chromatin stage and had a large nucleus occupying the greater part of oocyte. The germ cells of phase Ⅱovarium in four or five years were early growth period oocyte Ⅰ(60 -200μm) or perinucleolus stage and had 7 -26 nucleolus in them and phase Ⅲovarium in six or seven years were middle growth period oocyte I (200 -1600μm) . In this stage , oil droplets , yolk and pigment granules appeared at the periphery of the nucleus in a cytoplasm. The cell membrane had complete three layers. The germ cells of phase Ⅳovarium in eight years were late period oocytes I (1600 3300μm) . The nuclear membrane disappeared and the nucleus dissolved. Oocytes at the most advanced stage had the nucleus moving to the micropylar region of the animal pole. The germ cells of phase Ⅴovarium were ripe oocytes (3400 -3750μm) and were released from follicle to body cavity. After spawning , the phase Ⅵ ovarium had a few phase 2 ovum, so results show that the cycle of ripe ovarium again is about three or four years.

Abstract:Embryonic stem cells (ES cells ) are undifferentiated permanent cell line derived from inner cell mass cells and primordial germ cells of early developing embryos. Some growth factors were needed in culture medium to maintain LJ ES1 growth , proliferation and undifferentiation for a long time culture in vitro. Effects of various factors on the proliferation of LJ ES1 cells were examined by counting the number of multiplied cells in various mediums ( PESM0 -10 ) omitting one or several factors. Furthermore , emphasis was focused on LIF and bFGF factoreffects. LIFnearlyhadnoeffectonproliferationofearlyLJES1,justmaintainingitsundifferentiation,but it had a little effect on late LJES1;bFGF had a significant stimulative effect on the proliferation of LJES1. The number of LJ ES1 increased linearly at lower concentrations up to 2ng/ ml bFGF , a nearly 2 -3 fold increase was obtained ,at higher than 2ng/ ml concentration the proliferation2promoting effect was further enhanced but not significantly. Both sea perch embryo extract (PEE) and sea perch serum (FS ) promoted the proliferation of LJES1,buttheirproliferatingeffectonLJES1was notsosignificantasbFGF. Theadditionof2 -MEreduced the damage of peroxide on LJ ES1 cells , enhanced cell adhesion and promoted cell proliferation.

Abstract:Ozonation of water ammonia could get high eff iciency in the presence of bromide and was applied in many industry areas for treatment of waste water. In order to apply the method to treat fresh aquaculture waste water, it is necessary to investigate the effects of bromide on growth, thyroid hormones and its accumulation in tissues of fresh water f ish, and evaluate its safety. In our study, we chose the most general culture species of common carp ( Cyprinus carpio) as research object . The experiment was carried out in a group of 14 recirculating water culture tanks with 0. 5m3 volume of water, 18 f ish for each tank. During experiment, the f ish were fed with pellet food and the culture water was exchanged per 3 days. The added chemicals were NaBr and NaCl. The dissolution concentration of 6 test groups were 5mg#L - 1 NaBr, 15mg#L - 1 NaBr, 25mg#L - 1 1NaBr, 5mg#L - 1 NaBr 0. 1% NaCl, 5mg#L - 1 NaBr 0. 3%NaCl and 5mg#L - 1 NaBr 0. 5%NaCl and f resh water without any chemical was taken as control group. The common carp was examined in dif ferent concentration of NaBr and NaCl in fresh water. Growth rate and accumulation of bromide in different organs/ tissues were studied on 15, 30 and 45d respectively. At the same time, thyroid hormone was determined on 45d. The research showed that the growth rate of common carp could be promoted by adding NaBr in water and the difference of growth rate was signif icant in 15mg#L- 1NaBr ( P< 0. 05) comparing with the control group. Although the growth rate of all test groups was faster than control group, adding NaCl would decrease the growth rate. Thyroid hormone of test  groups was increased and it reached to maximal value in 15mg#L- 1NaBr ( P < 0. 01) . The effect of bromide on growth was in accordance with the concentration of thyroid hormone, but adding NaCl could not af fect the concentration of thyroid hormone. The accumulation of bromide was higher in liver and skin, and kept high level in kidney in all concentrations. The accumulation of bromide was 72. 40mg#L - 1 in muscle at 25mg#L - 1 NaBr. The accumulation of bromide could be decreased significantly in different organs/ tissues if NaCl was added ( P< 0. 01) . It was secure to aquatic life of freshwater when concentration of NaBr in water was lower than 25mg# L - 1 , and the accumulative amount of bromide in aquatic life of freshwater accorded with food health standard for human being . Based on the result, we can determine the adding concentration of bromide in aquaculture waste water treatment . So it is po ssible for us to ozone ammonia in fresh aquaculture by adding catalytic bromide and the ozonation of ammonia would provide new treatment technology of fresh aquaculture water.

Abstract:The study was designed to investigate the special amount of peptides which could be completely absorbed in blood circulation of grass carp. Four groups of grass carp were infused into the front intestine with 6.25%casein (CA ), casein enzymatic hydrolysate (CSP), casein acidized (FAA ) solution and normal saline (1mg?100g -1 weight ) . Blood was collected after 20 min infusion from tail vein. The results of analyses by HPLC showed that the total amount of peptides and the amount of some peptides in plasma of grass carp given CSP were significantly higher than those of the grass carp given CA , FAA and normal saline ( P < 0. 05) . The total amount of peptides in plasma of grass carp given CSP was increased by 18. 73 % compared with those given FAA. There was no significant difference of total amount of peptides in plasma of grass carp given CA , FAA and normal saline ( P > 0. 05) . The increase of peptides in plasma was closely related with the kind and amount of peptides in intestine. The study indicated that small peptides could be absorbed into blood circulation of grass carp .

Abstract:The productive biology of hard clam ( Meretrix meretrix Linnaeus ) cultured in South Zhejiang was studied by means of histological section in this paper. The reproducitive cycle , fatness , gonad development , breeding season of M . meretrix cultured in south Zhejiang are described. The reproductive cycle of M. meretrix was divided into 5 stages : proliferation stage , growing stage , maturation stage , breeding stage and suspensive stage. The spawning season was from late May to mid2August (21. 8 -31. 0 ℃) , and the peak of spawning occurred from late June to late July when the temperature was about 25 -30 ℃. The highest index of fatness on averagewasabout8.84%inJune,andthelowestwasabout3.21%inJanuary. Thesexsualmaturityat1year old M. meretrix was found. The relationship of full maturation and spawning with accumulated temperature is discussed in this paper.

Abstract:The survey on ecological environment and squid resources was carried out in the fishing ground of Ommastrephes batrami in the North Pacific Ocean( 152bE- 171bW, 39b- 42bN) from June to August, 2001. The results showed that average biomass of zooplankton was 92. 12mg#m- 3( 0. 81- 1035. 68 mg#m- 3) in the all water area, 113. 51mg#m- 3 in the middle water area ( 160b- 180bE, 39b- 42bN) and west longitude water area ( 170b- 178bW, 40b- 41bN) and 22. 89mg#m - 3 in the west water area ( 152b- 157bE, 41b- 43bN) ; the zooplankton abundance was mainly composed of Copepoda ( 42. 11% ) , followed by Thaliacea ( 30. 91%) ; Eucalanus pseudattenuatus, Calanus pacif ica and Dolioletta gegenbauri were main dominant species. Crustacean distribution also corresponded well with the f ishing ground, the centre of which was just located in or near the high abundance area of crustacean ( 50- 100 ind#m- 3) and high biomass area of zooplankton ( 250- 500mg# m- 3) . The distribution of Cephalopoda larva is also in or near the high abundance area of Euphausiacea and Amphipoda.

Abstract:Supported by the technique of GIS and database and based on the survey data of two cruises in February (dry season) and August (wet season) of 1999 , this paper analyzed and evaluated comprehensively the status of water nutrient in Kaozhou Bay by using the method of data interpolation and grid weighting scheme. In the dry season , the water quality accorded with the first class of sea water standard without any organic pollution , while in the wet season it was in the second class with obvious organic pollution and eutrophication occurring in the northwestern waters and the estuary of Jilong River. The distribution trends of the primary productivity were similar in the two surveys , which were high in the mouth of the bay and low in the middle and northwestern waters. The distributions of the food organisms were irregular in both of the surveys. In the dry season they were evenly distributed with most of the waters belonging to the second or the third level , and the dense area was found in the northwestern waters , the mouth of the bay and the waters around Jilong River , while in the wet season , the food organism level varied distinctly with the dense area occurring in the middle waters of the bay and the coastal waters along Wangjingzhou village. Compared between the two surveys , the levels of primary productivity and food organisms in the wet season were higher than those in the dry season.

Abstract:The estuary water after being disinfected and deposited was used as foundational water in experiment. The foam separator , pre2cultured biofilter and ultraviolet disinfector were applied to treat recirculating water in breeding for Macrobrachium rosenbargii larva. The quality of recirculating water was controlled effectively by the water treatment system. The water quality was controlled with traditional method in control pond , in which a lot of medicine and water exchanging was applied ,so the amount of water in test pond with no medicine or water exchanging was 67. 5 % less than that in control pond. The variety of main parameter of recirculating water in test pond during the experiment were as follows : NH32Nm:0 -0.010 mg?L -1 ,NO2 2N :0.01 -0.63 mg?L -1 ,pH: 7.48-8.37,CODMn : 5.42 -12.25mg?L -1 , bacterium : (4. 2 -130) ?103cell ?mL -1, vibrio: (0.2 -20) ? 102cell?mL -1. The survival rate of experiment pond was 40 % , which was 33. 3 % more than that in control pond. Good result was also obtained in the productive test , in which the survival rates of productive test pond and control pond were both 30 %. The model on recirculating water treatment in breeding larva of Macrobrachium rosenbargii is proposed according to the experimental result and breeding character of Macrobrachium rosenbargii.

Abstract:Based on polyploid induction method in shrimp established in our laboratory , triploid Chinese shrimp, Fenneropenaeus chinensis was induced by heat shock to inhibit meiosis ? . Triploid shrimps and their diploid siblings were challenged w ith white spot syndrome virus (WSSV) through oral administration or with Vibrio anguillarum by injection. Shrimps without pathogens challenge were used as controls. Hemocyte count and composition in hemolymph of diploid and triploid shrimp were compared. This is the first time to report the cell count and composition of hemolymph in triploid shrimp. It showed that pathogens challenge resulted in obvious haematological changes. A signif icant decline for hemocyte count in both diploid and triploid shrimp af ter 4 days challenge was observed. Hemocyte count of both diploid and triploid shrimp was reduced to about 10% of that of control. The composition of hemocytes either in diploid or triploid shrimp changed after WSSV challenge. The  amount of large granule cells ( LGC) decreased, while that of small granule cells ( SGC) increased. However, the amount of hyaline cells (HC) remained unchanged. Some abnormal structures such as vacant vacuoles were found in SGC and LGC of the infected shrimp. Hemocyte count of diploid and triploid shrimp decreased too after being infected with Vibrio anguillarum, and the range of decline was positively related with the injection dosage of Vibrio anguillarum. Triploid shrimp has larger hemocyte volume and lesser total hemocyte counts, which accounts for about 40% of that of diploid, but the hemocyte composition in triploid was the same as that in diploid. Results above provide basis and reference for stress resistance research on triploid shrimp.

Abstract:It is well known that the most pathogenic bacteria can produce various virulence factors and they play funct ion together and lead to the pathoenicity of bodis. The adhesion to cells or mucosa of pathogenic bacteria is the prime process which results in the infection of bodis. The adhesive factors of bacteria include pilus adhesion and non-pilus adhesion( such as f lagella, outer membrane proteins and hemagglusion etc. ) . The adhesion to tissuecells or mucosa of pathogenic bacteria mediating by pilus plays a key role in colonizing and propagat ing various virulence factors that result in the pathoenicity of bodis. In order to reveal the pathogensis mechanism of vibrio mimicus strain HX-4 in this study we used classic adhesive mode-l cell HEp-2 cells as cell model in vitro to test the adhesive ability of pathogentic vibrio mimicus HX-4 strain isolated f rom diseased Eriocheir sinensis to HEp-2 cells and the effect of receptors and antibody on the adhesion of the strain. At the same time, the invasive ability of the strain into HEp-2 cells was measured by lysiscounting assay. The results showed that vibrio mimicus HX-4 strain had invasive ability into HEp-2 cells, and it can adhere to HEp-2 cells in the way of assembly. That is to say vibrio mimicus HX-4 strain was positive bacteria of adhesion and the optimal adhesivetime was one hour. At the same time we also found that mannose and antibody could inhibit adherence effectively. These results demonstrated that there was D-mannose structure among the adhesive receptor structure and the adhesion of vibrio mimicus HX-4 strain may also include f lagella, outer membrane proteins besides pilus.

Abstract:The scallop, Chlamys farreri , is one of the major species cultured in North China, and its culture in commercial scale has been performed for more than 20 years. The highest production of about 1 million metric tons has been achieved in 1996. The great expansion and intensif ication induced the occurrence of disease since 1990. s, and became epizootics f rom 1997. It is believed that the disease so called -Scallop Acute Viral Necrot ic Disease. ( SAVND) has becoming the major limiting factor in the development of the industry, and has hindered the economic process in the coast area of the region. The earlier investigation from our research group showed that the disease occurred in the second-year-old scallops, which had an averaged shell height of 5. 0 ? 0. 9 cm in Jiaozhou Bay. The mortality f irstly occurred in the early July and peaked in the end of the month, as the temperature reached the highest period ( 25- 26. 7bC) in the year. Subsequently, the disease subsided in the early August and the cumulative mortality could be above 90% . In most cases, the morbidity was acute and the course of disease was only about one week. In order to make sure the main pathogen of this disease, an intensive investigation was undertaken recently. Firstly, this paper is to report histopathological and microbiological evidence of the cultured scallop on a diseased condition, and described a possible virus-like etiology causing the massive death of the scallop. Electron microscopic examinations of ultrathin sect ions reveal the presence of spherical virus-like particles in the digestive gland, mantle, kidney, and the intestine of moribund scallop Chlamys farreri collected from 6 epidemic areas during a severe mortality on the coast of Shandong ( China) in 2000- 2002. Relevant pathologic change can be observed. Virions are approximately 130 to 170 nm in diameter and have a bilaminal envelope, while the nucleocapsids are 90- 140 nm. Spike of envelope, observed by negative stain after isolation and purif ication, are 20nm in length. The virus occurs and assembles in the cytoplasmic vesicles without occlusion. Next , art if icial infective experiments and back-check of infective samples were taken to confirm whether the scallop disease was aroused by the virions. Artificial infective experiment s of healthy scallop were carried out by injection and by waterborne of viral preparation isolated from moribund scallop of epidemic area. The results showed that the injection and waterborne administration had high mortality of 75% and 68. 7%, respectively. Meanwhile, the control had 87. 5% survival rate. The symptom appeared after artificial inoculation was similar to those shown by diseased scallop under natural conditions. Moreover, the virions could be detected in infected cell of diseased scallop in the infective experiment by electron microscopy, in which the morphological and pathological characters were ident ical with those formed in diseased scallop under natural conditions. These results strongly support the conclusion that virus is the causative aet iology for the abnormal mortality.

Abstract:Based on the production survey of the pair trawl and otter trawl fisheries in Minnan Area, Fujian Province, the provincial statistical data and some records related to the f ishing operation, the DEA method was applied to analyze the fishing capacity of trawl f isheries in different areas of Fujain, the fishing capacity of different f ishing methods in Minna Area, Fujian, and the factors affecting the fishing capacity. Then the f ishing capacity calculated by DEA was compared with the catch per unit effort. The result showed that the capacity utilization of f ishing fleet in different areas of Fujian was significantly dif ferent . The lowest in 1999 and 2001 was 19. 4% and 19. 9%, respectively. The average capacity utilizat ions for whole province were low. They were 64. 3% and 67. 5% respectively for 1999 and 2001. The investment of Fujian Province was too great in the number, the total power, and the gross tonnage of fishing boats. The factors that affected fishing capacity would vary w ith different f ishing methods. The power of boats and the number of fishing days in a year were the main factors that affected the capacity both in pair trawl and otter trawl. To exchange the results between CPUE and  capacity utilization, the precondition was that the factors used to calculate them must be the exactly the same. When CPUE method was used to calculate fishing capacity , the number of factors was quite limitative. But using the DEA method, we could get different information of fishing capacity concluded by different calculative factors, so the results were more accordant with the facts.

Abstract:The paper is a review of the studies on the temperature of the thermal tolerance in fishes. It was described from four aspect : (1) The key parameters of temperature of thermal tolerance in fishes ; (2) The influence factors of temperature of thermal tolerance in fishes ; (3) The research methods of thermal effect of fishes ; (4) The evaluation of effects of thermal pollution on fishes , especially , with the coastal power station will be built in China recent years , the effects of thermal discharge water on the marine fisheries resource were discussed.

Abstract:Currently used seawater pond culture models are evaluated , and principles and methods in optimizing pond culture model are discussed in the present paper. The author indicates that application of the traditional polyculture has been limited in single pond. Inputted nutrients such as feed and fertilizer can’t be efficiently utilized by animals cultured in a pond with the traditional polyculture , resulting in huge waste discharge , which is regarded as a pollution source to coastal regions. The author suggests it should be possible to put several seawater ponds with different stocking structures together and optimize stocking and management systemically. Compared with the traditionally polycultured seawater ponds , ecological benefits and nutrients transport in the systemically optimized ponds would be amplified. The production performance of the systemically optimized ponds , therefore , would be increased and their pollution would be reduced.

Abstract:As a main protein source in aquafeeds , fish meal has been extensively studied. Fish sources , freshness , processing temperature , lipid quality and microbiological index are five main aspects of the evaluation of fish meal quality. This paper reviewed the researches on fish meal including the evaluation of fish meal quality , the use of fishmeal and the environmental problems. Biogenic amine is the main potential toxin in decomposed fish meal including mainly histamine , cadaverine , putrescine and tyramine and most studies showed that they could affect the fish growth performance and health. The determination of protein digestibility of fish meal includes pepsin2digestion method , animal test , capillary electrophoresis , etc. The content of phosphorus in fish meal and its utilization can introduce pollution to water bodies and the use of alternative protein and improvement of utilization of fish meal can help to reduce the pollution from fish meal.

Abstract:30 ayu ( Plecoglossus altivelis ) samples were collected from the cultural net in Fuxi Town , Ninghai County , Zhejiang Province. Polyarylamide gel electrophoresis was used to detect the expression of isozymes in 8 organsortissues: eye, liver, kidney, muscle, spleen, heart, gill andpectroralfin. ADH,CAT,POD,ACP, ALP,EST,LDH,MDH,ME,GcDH,SCD,GDH,SDH,SOD,ATP were analyzed and the biochemical genetic results showed that 15 isozymes were coded by 55 gene loci ,12 of which (ADH21 ,ADH24 ,CAT22 , POD23 ,ALP2 2 , EST23 , EST24 , LDH25, ME24 , GcDH24 , GDH, SDH22) were found polymorphic. The population of ayu ( Plecoglossus altivelis) in Fuxi town showed the higher genetic diversity when compared with other freshwater fishes,with21.8%oftheproportionofpolymorphiclociand0.0459oftheaverageheterozygosityperloci. And we think the expression of CAT, POD and SOD of ayu ( Plecoglossus altivelis ) can be used to evaluate the influence to body2protecting system of the fish when environmental factors were changed. The expression of isozymes in pectroral fin can be used as genetic marker in breeding of ayu ( Plecoglossus altivelis).

Abstract:Leukocytes are key cells for the specific and nonspecific immune systems , it expresses different kinds of biodefense2related peptides and proteins including specific and nonspecific antimicrobial agents , and activators and regulators of the immune system. However,we know very little about the cellular interactions that initiate and control the adaptive immune response in fish. In order to clone and study immune2related and biodefense2related genes in carp ( Cyprinus carpio L. ) leucocytes , the cDNA library of carp leucocytes was constructed. First , the carp leucocytes were isolated from the peripheral blood of normal carp , total RNA of leucocytes was extracted and from 2 ?108 leucocytes cells , and the output was 216μg , ODA260/ 280 > 1. 8 , mRNA was isolated with a column of oligo (dT) cellulose. Second, single2strand cDNA and double2strand cDNA were synthesized from 5μg mRNA using Stratagene HybriZAP22. 1 XR cDNA synthesis kit , then ligated to EcoR I adapters , size fractionating with CHROMA Spin2400 column. Finally cDNA were ligated into HybriZAP22. 1 vector and packaged in vitro. The obtained carp leucocyte cDNA library contains 5. 79 ?106 recombinants , the percentage of vectors with inserts was 99. 4 % and the average inserts size were between 0. 4 ?103 -3.0 ?103bp. After amplification , the titer of amplified library was 4. 22 ?109pfu?mL -1 . This normal carp leucocytes cDNA library gives an ideal basis for further study of carp immune system.

Abstract:The full length cDNA encoding growth hormone of a freshwater f ish, Lepomis cyanellus, (LcGH) was cloned from pituitary RNA with RT-PCR, 3..and 5.. RACE ( rapid amplif ication of cDNA ends) . The LcGH cDNA ( Genbank No. AY530822) , about 989nt ( nucleotide) long, consisted of a open reading frame with 615nt long, 5..and 3..untranslated regions with 93nt and 224nt long respectively, and a 57nt poly ( A) tail. The DNA sequence analysis showed that there are typical Kozak sequence and polyadenylation signal. The pregrowth hormone peptide of 204aa deduced from LcGH cDNA included a putative signal peptide ( 17aa) locating in its Nterminal. There exist a Asn-Cys-Thr glycosylation site at amino acid 201, and 4 cysteine residues ( No. 69, 177, 194, 202) that are essential to construct two S-S bonds in this pregrowth hormone peptide. Homological comparision among LcGH and other species growth hormones showed that There is high homology ( more than 85% ) between growth hormone of Lepomis cyanellus and that of most perciformes fish, but low homology ( less than 70%) in comparison with other species such as Siluriformes and Cypriniformes f ish.

Abstract:Mature eggs of Oreochromis aurea were obtained with artificial reproduction technology , and the hybrids were acquired with Siniperca chuatsi ( ♂) using artificial insemination . Genomic DNA of O. aurea ( ♀), S. chuatsi ( ♂) and their progeny were examined using RAPD method. Only 2 primers (S336 , OPZ06) of screened 11 random primers could be amplified into two specifically RAPD bands on progeny which were the same as those of S . chuatsi ( ♂) and did not exist in O. aurea ( ♀) , and other amplified bands on progeny were all from O. aurea ( ♀) . Genetic similarity index was 0. 858 between the progeny and O. aurea ( ♀) , while that was 0. 049 between the progeny and S . chuatsi ( ♂). This indicated that the genetic substance of progeny was mostly from Studies on hereditary relationship between Oreochromis aurea ( ♀), YANG Hong , XIA De2quan ,LIU Lei , WU Ting2ting ( Freshwater Fisheries Research Center , Chinese Academy of Fishery Sciences , Wuxi 　214081 , Siniperca chuatsi ( ♂) and their offspring China) O. aurea ( ♀) . The primary function of sperm from S . chuatsi ( ♂) was stimulating development of eggs from O. aurea ( ♀) , at the same time little genetic substance of S . chuatsi ( ♂) appeared in the progeny , which laid the foundation for breeding of fine varieties having characters of O. aurea ( ♀) and S . chuatsi ( ♂).

Abstract:The effect of salinity on embryo and early larva development of Dentex tumiforns was discussed. Floating forms of egg in different salinities , optimal salinity for embryonic development and early larva growth was studied. The results showed : 1. In immobile condition , all eggs sank at salinity of 32. 0 , most of eggs suspended in the middle of water at 34. 0 , and all eggs floated on the surface when salinity above 36. 0. 2. Eggs did not hatch out at salinity of below 10. 0 or above 60. 0 and the death time of egg gradually moved up with increase or decline of salinity. Eggs hatched out at salinity range of 15. 0 and 50. 0 ,including abnormal larva. There was indistinct difference in speed of embryonic development (about 36 -40h) within the salinity of 15. 0 and 50. 0. However the salinity had a great effect on larval survival after hatching and abnormal rate. The relation between hatching rate and salinity variation showed parabola but abnormal rate showed inverted parabola. The hatching rate was 81 % -86 % and abnormal rate of yolk sac larva was 27 % -30 % in suitable salinities of 27. 0 -39. 0. The hatching rate was 89 % -91 % and abnormal rate was 13 % -16 % in optimal salinities of 33. 0 36.0. The oil ball of abnormal larva was located in the central or front position. With increased extent of salinity , spondyle of larva bended and number of larva with arrhythmia increased. 3. The optimal salinities were 30. 0 -35. 0 based on SAI. The test with SAI showed that SAI of early larvae was 41. 25 -47. 53 at salinities of 30. 0 -35. 0 , the yolk and oil ball of 7 -8 days larva was completely absorbed with a survival rate of 88 %.

Abstract:The specimens for biological study were collected from the spawning and feeding ground of Ammodytes personatus and the A . personatus fishing condition data for the f ishery management were collected in 1999- 2003. The compositions of food organisms of A. personatus in the coast of southern Shandong peninsula include the Copepoda, Chaetognatha , Amphipoda, Decap oda and Euphausicea. From summer season to the spawning stage, A. personatus distributed in the northern Yellow Sea do not take food. The absolute majority of A. personatus mature during their first year of life and this f ish spawns once a year. The main spawning season is f rom the end of October to November. In the earlier stage, the temperature for the spawners is about 11. 8bC and salinity is about 31. 686. The individual absolute fecundity ( eggs) ranges from 0. 45 @ 104 to 5. 10 @ 104( mean 1. 79 @ 104 ) . The relation equation between absolute fecundity and net weight ( g ) is E = 1867. 7129610 W1. 209953873. The relation equation between absolute fecundity and body length ( mm) is E = 0. 000175549 L 3. 70261414 . The catch of A. personatus consists of 3 year classes, from age group . to age group ? , excluding the age group 0. The otolith was used for age determination. To cite 2002 as example, the length-weight relationship is calculated to be W= 0. 001906 L3. 17039. The faunal characteristics of f ishes of the Yellow Sea is quite different in composition from the other parts of the China Sea. Almost 90% of the Yellow Sea f ish belong to warmtemperate and warm-water fishes, only a few species belong to cold-temperate species. As a cold-temperate species, A. personatus is valuable legacy of ecosystem evolution of the Yellow Sea. In view of the above, sustainable utilization of this fish species is more important .