Abstract:Dose-response inhibition curves for serial dilutions of sera and pituitary homogenates f rom the bag rid catf ish M .macropterus (Bleeker)parallel that for the common carp grow th ho rmone (cGH), so the radioimmunoassay for cGH w as used to assay the blood and pituitary GH levels of the catfish .Seasonal changes w ere found in both pituitary GH content s and serum GH levels .Seasonal changes in pituitary GH contents w ere marked by tw o distinct peaks , one w as in March and the other was in August , just anterio r to and posterior to the gonadot ropin (GTH)peak(April to July)of the pi tuitary .From April to July , the reproductive period of the fish , and f rom November to February , the overw inter period , the pituitary GH content s w ere low and w ith mino r variat ions .Influenced by w ater temperature and pho toperiod , the lowest level of serum GH w as observed in w inter and a prog ressive increase w as found in spring and summer . But a sig nificant increase w as found at the end of summer (July), and remained a high level in autumn .Seaso nal changes in serum GH levels were also co rrelated to reproductive cycle .The lowest serum GH level w as observed in the resting period , elevated g radually with the recrudescence of the gonads , increased sig nificant ly at the spaw ning period , and got the highest v alue in the sexual reg ressed period .These results were in accordance w ith those obtained in common carp and g oldf ish .

Abstract:T his paper deals w ith the effects of different lig ht intensity on the growth, development and feeding of larval L imanda y okohamae. The result s are as follows: Light has important inf luence on the grow th, development and feeding of larval Limanda yokohamae. The body length and height of every group of larvae on the twenieth day all show s fair evident difference. Duncan New Mult iple Range T est show s: Under the light intensity rang ing f rom 40 to 60 lx , the grow th and development of larvae are the best. Within the lig ht intensity of 40 to 7000 lx , the stronger the light intensity is, the worse the grow th is, the lower the surv ival rate is, the more the abnormal larvae are. The larvae under complete darkness and under the lig ht intensity of 3 to 6 lx are all dead on the 12th day because of starvation. In the yolk-sac stage, the g row th of every group of larvae is not influenced by the ex ternal env ironment and is similar to all. From the 4th to 20th day, the grow th of body length of 5 groups of larvae under 40 to 7000 lx show straight line relat ion to age, and the g row th of body height show s exponential funct ion relat ion to age. From 40 lx to 7000 lx, the feeding intensity ( 10: 00- 14: 00) of larvae is discreased w ith the increase of light intensity. If the appropriate lig ht intensity is g iven between 18: 00 and 22: 00 , the larvae can also have fair feeding intensity . The suitable light intensity for larvae before the 20th day is 40- 600 lx.

Abstract:Studies w ere carried out on the gonadal of pike conger , Mureanesox cinereus w ith regard to it s morphological and histolog ical features and annual maturatio n changes .The morphological observations show that , the ov ary and the testes of pike conger consist w ith many lamella ovaries and lamella testes respectively .The morphological structure of ovary and test is is largely different f rom those of most other f ishes .Histological observation on the g onadal show s that , some ovaries of individual pike conger develop into the maturation stage in the late April and individuals with matured ovaries increase sharply in May .So the reproductive period of pike conger is betw een May to August and the period betw een June to July is the most active . Microscopic and submicroscopic observation aslo show that , the sperm of pike conger has a sicklelike head and a relatively short tail .

Abstract:The best w ater temperature ranges f rom 20 ℃ to 25 ℃ for Amp ullar ia gigas culture , and the suitable air temperature ranges f rom 20 ℃ to 35 ℃ fo r ova hatching .There is ex tremely g reat negative correlation betw een hatching time and average temperature of ova w ith correlation coef ficient r =-0 .942 .Amp ullaria gigas can no t live through winter under natural ecological conditions north to Changsha , but can live if the temperature of water is kept above 10 ℃ in winter .Mature and young Amp ullar ia gigas can lie dormant for three months w ith 57 . 6 % of survival rate without w ater in laboratory under air temperature 2 -17 ℃, but can not survive out of laboratory in winter .

Abstract:Three cultured populat ions (Xianghu , American and Shashi)of Oreochromis nil loticus and one cultured population of O .aureus were examined using RAPD method .12 primers w ere screened out of 20 random primers , and each of the 12 primers revealed inter-or/and int rapopulation genetic variation .There were four species-specif ic amplification bands (sizing 900 , 1500 , 1700 and 730 bp respectively)of primers OPZ06 , OPZ10 , OPZ12 and OPZ19 , each of w hich could be used as molecular genetic markers to identify O .ni lot icus and O .aureus .Genet ic similarity indices (S)suggested that the three populat ions of O .ni loticus maintained the higher deg rees of the int rapopulation genetic variation (S for the three populations of Xianghu , American and Shashi w ere 0 .798 , 0 .795 and 0 .824 respectively), and O .aureus had the smallest degree of genetic variat ion(S =0 .950)because of two times of genetic bot tleneck ef fect .The data suggest that there is the genetic potential of developing new O .niloticus varieties , w hile there is relatively small genetic po tential in O .aureus .Inter-specific genetic distances between O .aureus and three populations of O .ni lot icus w ere 0 .285 , 0 .262 and 0 .344 , respectively , which suggest that the of fspring of O .aureus and Shashi population of O .niloticus w ill develop st ronger heterosis than that of other tw o cross combinat ions .

Abstract:This paper analyzes the energy ut ilization efficiency on every sectio n in dif ferent main cultivated f ish ponds .In the pond of main cultivated g rass carp , its transforming eff iciency of the to tal supplement energy 、photo-synthetic energy and creature energy were 9 .86 %, 6 .92 % and 10 .10 % respectively .Meanw hile , the consumed energy of culturing one to n fish yield was 46 .64GJ , 66 .46GJ and 45 .54GJ respect ively .In the pond of main cultivated silver carp and big head carp , the appropriate data were 8 .43 %, 3 .75 %, 8 .66 %, 46 .99GJ , 105 .52GJ , 45 .73GJ respectively .As the dif ference of main function in tw o ponds, there w as some diversity for utilizat ion the radiation by silver carp and big head carp .The net conversion ef ficiency w as almost equal, w hich was f rom the primary productivity to the crops of the filtered food f ish .The coeff icient w as 1 .45 % and 1 .43 % in main culturing grass carp fish pond and in main culturing silver carp and big head carp fish ponds .Based on the eco-economic index EY , the producing style of main cultivated grass carp was superior to that of main cult ivated silver carp and big head carp .

Abstract:The ni trogen fix ation in shrimp culture enclosures at dif ferent culture sty les w as measured using acethlene reduction method .The results were as follow s :In all enclosures , the nit rogen fixation rates w ere the highest 2 .62 μgN/(L·hr)fo r Y -4 , the enclosure monocultured w ith shrimp Penaeus chinensis and 2 .65μgN/(L·hr)for Y -5 , the enclosure polycultured w ith shrimp and bay scallop , the lowest 1 .53μgN/(L·hr)for T -5 , the enclosure polycultured w ith shrimp, tilapia Oreochrromis niloticus and const racted tanglus Sinonovacula costricata , 2 . 30μgN/(L·hr)for Y -6 , the enclosure polycultured wi th shrimp and constrcacted tang lus, and 1 .89μgN/(L ·hr) for Y -7 , the enclosure polycultured with shrimp and tilapia .In the enclosures, the high ni trogen f ixatio n rates may co ncern with the low avaliable nitrogen concent ration and the low N/P ratio , compared w ith the Redfield rat io .The nit rogen fixation blue-g reen algae were mainly Chroococus , and then Nostoc .Estimated nit rogen fixation as nit rogen input s for dif ferent enclosures was :17 .71g for Y -4 , 19 .63g for Y -5 , 90 .5g for Y - 6 , 10 .59g for Y -7 and 7 .99g for T -5 , respectively .

Abstract:Comparative studies on ecological efficiency , production and economic profit s of different polyculture sy stems of Chinese shrimp (Penaeus chinensis Osbeck)w ith red Taiw an tilapia (Oreochromis mossambicus × O .ni lot icus), bay scallop (Argopecten irradians), common sea-perch (Lateolabrax japonicus)and constricted tagelus(S inonovacula constricta)as aux iliary members separately in closed seawater ponds were conducted by using 50 land-based enclosures of each 5 .0 × 5 .0 ×1 .8m in 1996 .In result s , the nit rogen conversion efficiencies by the animals cultivated , the polyculture systems were ranged in a descending order as :“common sea-perch -Chinese shrimp -tilapia polyculture”(PST)(30 .91 %)>“Chinese shrimp-bay scallop polyculture”(SBS)(21 .01 %)>“ex tensive Chinese shrimp-tilapia polyculture” (STM)(20 .12 %) >“intensive Chinese shrimp-tilapia poly culture” (STF)(17 .81 %)>“Chinese shrimp-const ricted tagelus polyculture” (SCC )(16 .93 %)>monoculture of Chinese shrimp (S)(11 .52 %), suggesting that ecological efficiencies of the poly culture sy stems were higher than those of the monoculture ones .By ratio of output to input , the polyculture sy stems were ranged in a descending order as :S TF (1 .99)>STM (1 .98)>SBS(1 .53)>S(1 .38)>PS T(1 .30)>SSC (1 .23).While by the net incomes (×104 yuan RMB/hm2), the polyculture sy stems w ere ranged in a descend order as :PST(2 .57)>S TF (1 .62)>SSC(0 .91)>STM(0 .81)>SBS(0 . 76)>S (0 .54).All the results indicate that polyculture of the shrimp w ith tilapia , bay scallop or const ricted tagelus is characterized by bet ter benef it than monoculture is .

Abstract:A method of indirect agglut inatio n of red cell w as established , by w hich antibody in sof t-shelled turtle , Triony x sinensis , w as detected .It demonst rated that the highest titer could be obtained w hile the concent ration of sensitizing antigen w as 3 ×108cfu/mL for bacteria and 2 .0mg/mL for BSA , and that of sensitizing red cell of man or sheep w as 2 .5 %.There was no sig nificant dif ferences w ithin 80d in the result s of detecting w ith sensitive red cell , to w hich stabilizer w as added .Furthermore , the sensitivity of this method w as higher , and the method also better in accuracy , specifici ty and duplici ty .

Abstract:T he cause of Eriocheir sinensis disease, w hich w as called as .. Trembling Disease.. by the f ish farmers, w as studied. Ex aminat ion by electron microscopy show ed that there w ere a numbers of v iral part icles in the t issues of heart、abdominal nerve ganglion、g ill、intestine and hepatopancreas and there was no envelope outside v irion. T he diameter of virion was approx inately from 28nm to 30nm. Virions occurred in the cy toplasm and did not form the inclusion body. According to the characters of viral morphology and dyeability, the virus belonged to Picornaviridae. The healthy Eriocheir sinensis after injected w ith f iltered fluid from ground tissues of diseased Eriocheir sinensis appeared the same symptom of legs t rembling as that of the natural diseased one. This result conf irmed that the picornavirus was pathogen of the disease. The histopathological changes: cells oedema, karyolysis or karyopyknosis, mitochondria oedema, mitochondria cristae broken、curved and necrolysis. The necrotic cells became the substances of no cell st ructure in the severe necrot ic areas.

Abstract:The feeding and g row th of Japanese common sea urchin, St rongylocent rotus intermedius fed on L aminaria j ap oni ca , Undar ia p innat if ida and Ulva sp. in 10. 0- 25. 0 .. and fed on the mixed algae combined with Sar gar ssum horneri , Chondr us sp. in 15. 4- 17. 8 .. w ere determined respect ively . The relat ionship betw een sea urchin body weig ht ( G ) and test diameter( D) is G= 0. 43132D 2. 9958 . And the results also show e that the daily feeding rates of sea urchin fed on the three kinds of algae are dif ferent and change w ith the water temperature. The daily grow th rates are 0. 5 .. 10- 2- 3. 0 .. 10- 2cm/ ( ind..day) of juvenile sea urchin ( 1. 0- 3. 6cm in test diameter ) fed on L . j aponica, U. p innat if ida and Undaria sp. in 10. 0- 25. 0 .. . T he daily relat ive growth rate is the biggest in 19. 0 .. in the juvenile ( 1. 0cm in diameter) , but in 16. 0 .. for adult ( 3. 6- 5. 0cm in diameter) . The body w eight g row th rate is negat ive of adult sea urchin at 25. 0 .. . For 1. 0 - 5. 3 cm sea urchin, the ability for ant-i hig h temperature decreases w ith the increasing of test diameter. T he color of body and sex gland of sea urchin vary w ith it s fed algae. It also indicates that the sequence of selective feeding on five kinds of alg ae is L . j ap onica, U. p innat if ida, S . hor ner , Chondrus sp. , Undar ia sp. The result of hungry test show s that the sea urchin can be hung ry for 15 days in 21. 6- 27. 4 .. , and the ant-i hungry ability for 1. 7- 3. 5 cm is st ronger than the others of 1. 0- 5. 2 cm sea urchin.

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