Abstract:A detailed resear ch is reported in this pa per on the biolo gy of age, gr ow th, feeding habit, r epr oduct ion o f Odontobutis potamphila ( G..nther ) . The oto lith is the best indicator in ag e de terminat ion, w ith ve rtebra and scale as reference. The pe cto ral r adial bo ne is not re liable in age determinat ion. Of all the aquat ic ca tches the age .. and .. co ntr ibuted 85% o f the to ta l number in f iv e.. ye ar gro ups f rom 0 to ... The radius o f oto lith a nd body length are in a signif icant line ar corr elat ion, w hich ca n be described by the fol low ing equat ion: L = 5. 313 3R - 0. 069 03. The relat ionship between bo dy length and bo dy w eight (W) and net w eig ht (W..) ca n be described by the fo llow ing equat ion: .. W= 0. 022 416L3. 086 7; W..= 0. 024 98L2. 974 7. The f ish mainly feeds on juv enile f ish and shrimps, but on less amo unt o f mo lluscs and insect s. The co urse of o varia n maturat io n can be div ided into six sta ges and .. ~ .. .. o r .. stage. The f ish releases two batches at least in a breeding season. The breeding se ason is betw een March and June. The nest preferences are w idely given to many kinds o f substances, such a s gr ass ro o t, tit le, some and other materia ls. The egg mass can be fo und on the top o r side of the nest . The indiv idual abso lute f ecundity ranges f rom 2 645~ 7 708 eg gs and individua l re lat ive ranges f rom 56~ 163 eggs.

Abstract:Black carps ( My lop hary ngodon p i ceus) var ying f rom 5. 6mm to 330. 0mm in to tal length ( n = 370) w ere dissected and measured w ith micro sco py, and then the specimens wer e observed thro ugh light and scanning electr on micro sco pye. The result s wer e as fol low ing: 1. With the gr ow th o f body length, the number o f g ill rakers a nd distance betw een them increa sed. When total le ng th rea ched 141. 0mm, gil l rakers w ere 19 and did not incr ease any mo re. The reg ression equat io n o f distance between g ill rakers( y , mm) to bo dy length ( x, mm) was: y= 0. 0252+ 0. 006 4x( n= 265) , r= 0. 988 5> r 0. 001= 0. 321 1. 2. The size and thickness o f ho rny pad increa sed w ith the gr ow th o f body length. The regressio n equat ion of hor ny pad le ng th ( y, mm) to bo dy length ( x, mm) w as: y= 0. 021 17 0. 060 1x( n= 227) , r= 0. 922 8> r0. 001= 0. 321 1, and the reg ression equat ion o f hor ny pa d thickness ( y , mm) to bo dy length ( x, mm) w as: y= 0. 060 5 0. 024 8x ( n= 215) , r= 0. 970 8> r0. 001= 0. 321 1. 3. When total length w as ar ound 7. 6mm, o rigina l teeth develo ped l ike co ne, and dental formula w as 1, 2/ 2, 1. When total length w as f rom 8. 0mm to 28. 5mm, phary ng eal teeth changed 3 t imes in successio n, and dental f ormula changed f rom 3/ 3 to 4/ 5. It w as ca lled t ra nsit io nal teeth pa ttern. When total le ng th was ove r 31. 5mm, phar yngeal teeth dev eloped and changed constantly . At that age, phary ngeal teeth reached the 5th generat ion as mola r. They w ere ca lled f ixed pat tern teeth, and denta l fo rmula wa s 4/ 5. 4. The fo lds and length o f intest ine length increased too w ith the bo dy length. When to tal length w as f rom 6. 7 mm to 10. 6 mm, intestine w as st raig ht. When to tal leng th w as 17. 0 mm, two intest ine fo lds develo ped. When to tal le ng th w as 24. 0 mm, 4 intest ine folds formed. Whe n total length w as 67. 4mm, ther e wa s 6 intest ine f olds. Af ter tha t, there w as no develo pment . When total leng th wa s f rom 6. 7 mm to 311. 0 mm, the avera ge value o f intenst ine length to body leng th w as 0. 522 3 ? 0. 040 3 to 1. 275 ? 0. 209mm. The relat ive intest ine leng th of adult f ish w as f rom 1. 4 to 1. 5. The fo llow ing quest ions w ere discussed: 1. Feeding characte rist ics o f black car p. 2. The stag e and co rre lat ivity of po st-embry onic dev elopment o f digest ive or gan ' s quant itat ive cha racter s. 3. The relat io nship betw een the deve lopment of quant itativ e char acters o f dig est iv e o rgan and the tr ansformat ion of feeding habit s.

Abstract:Takif ugu obscur us , popula rly named o bscure puf fer, is a f ish o f river-to-sea mig rat ion. No rma l se xual ident if icat ion metho d f ails w hen in repro ductio n per iod, because of no rema rkable dif ference between indiv idual in se co ndar y chara cters. A comprehensive .. 2.. 14.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 水.. 产.. 学.. 报.. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. .. 20 卷..  se xual ident if icat ionmetho d based on fe ature and posture wa s applied to 1 038 ind. o f puf fer, w hich w ere caught f rom March 15 to May 30 in 1995 in the lower a reach o f Yanqt ze Riv er f rom Yizheng to Taizho u, w ith in a dista nce of six ty kilometer s. The accurate percentage reaches 95. 4%. This metho d do es no t injure the sample, and it is so simple that it co uld do ev en when the puf fer is in a state o f f ree sw imming in po o l. The method, i. e. the f ish behav iour pattern metho d, o f f ish sex-ident if icat io n is reported fo r the f irst t ime. The study of fers a new method on the sexual ident if icat ion o f f ish, a nd it has certain co nt r ibut io n to the art if icial propag at ion a nd pro duction o f f ish.

Abstract:Age a nd growth o f crucian car p ( Car assius aur atus) in Dali Lake, a sa linealkaline la ke situated in the Inter-Mongo lia platea u were studied. Bo th the third ray o f anal f in ( Spino us so f t ra y) and scale we re used as the materia l fo r a ge determinat io n. The result show ed that the scale w as a better mater ial fo r age determina tio n at the age below 5, whi le the third ray o f anal f in w as a superior o ne at the age 5 and abo ve. The V on Be rta lanf fy grow th equat ions as fo llow s: Lt= 30. 1[ 1- e- 0. 179 7( t + 0. 558 9) ] ; .. Wt= 832. 3[ 1- e- 0. 179 7( t 0. 558 9) ] 3 which wer e established based o n the age, length at age and w eight a t age, which indica ted a higher growth speed than that in 1970 ' s. Considering the decl ining o f the yields in r ecent years, w e suggest her e tw o management measures o f impr oving spaw ning co ndit io n and co ntr ol the capture size f or the conserv atio n o f resour ce.

Abstract:Acquired St ra ins, w hich wer e iso lated f rom naturally infected so f t-shelled turt les and identif ied by the bacter io logical metho d, w ere Aeromonas hydr op hila. D isease d sof t-shelled tur tles we re letharg ic and appe ared hyperaemia in neck, mouth, nose, the t ip of tongue, and ser ious hyperaemia, haemo rrhag e, ulcers, scar s in the abdomen. Mo uth and no se w ere running f luid w ith bloo d. Liver, kidney and spleen w ere oedema, with some necro t ic foci. Histopatholo gical changes: Many bacter ia invaded lung, kidney, spleen, blo od, heart and muscle, causing haemor rhage and extensive t issue damage, w here cells appear ed oedema, granular degenerat io n, hya line degener atio n and necroly sis. Blo od vessels wer e serio usly damaged, and their epithelial cells were necr osis and fel l aw ay. A large number of erythro cy tes in the bloo d v essels a nd t issues w ere deformed, bro ken and haemo lyzed, w hich led to haemo lyt ic a nemia. The number o f leuco cy tes decreased in the blo od, and ther e w as no inf lammator y r espo nse aro und the necro t ic fo ci. Ex tensive ly damaged blo od cel ls, hear t t issue a nd se riously ne cr ot ic lung a f fected oxy gen ex cha ng e, deseased so f t-shelled turt le s died due to dif f icult br eathing. Necro t ic Liv er, kidney and spleen lo st the ir funct io ns, w hich facilitate d the death o f diseased sof t-she lled turt les. Histopatho logical co urse show ed that the disease w as septicaemia. Thera py of ser iously diseased so f t-shelled turt les was tha t their external ulcer s w ere sw abbed w ith ..YU TAI-8" dr ug, and ..Z HI BIE LING-2" dr ug w as injected into their hind legs. Slight ly dise ased so f tshe lled tur t le s w ere fed by the foo d inco rpor ated w ith ..ZHI BIE LING-1 " drug . Meanw hile, w ater quality wa s impro ved. The to ta l cure r ate w as ov er 90%. Lastly , the comprehensive prevent ive measur es aga inst so f t-shelled tur tle disea se w ere mentio ned.

Abstract:The changes o f grow th, total lipid content and fat ty acid composit ion o f N . clost erium , N . p leacea and Pavlova sp . culture d at dif ferent temperatur e w ere investig ate d. As essentia l fa tty acid ( EFA) o f la rval o f shrimp, crab, bivalves and marine f ish, 20B5( n - 3) wa s pr ov ided by N . clost erium and N . pl eacea , 22B6( n- 3) by Pavkova sp . . Opt imum temperatur e fo r maximum l ipid and EFA pro ductio n tog ether w ith faster growth was 20 e fo r N . closterium a nd Pavlova sp . , 15 e fo r N . p al eacea.

Abstract:Proto pla st s f r om one species of br ow n alga Sargassum f usif orme ( Harv. ) Setchell had been obta ined w ith the applicat ion o f wa ll degrading enzymes. The inte rnal facto rs and external co ndit ions o f the iso latio n o f proto pla sts , such a s kinds and co nce nt rat io ns of o smo regulate d re agent, kinds and combinat ions of enzymes, isola ted tempe rature a nd pH, t ime o f ma ter ial collect ions and part of thallus, are def inited now . Hav ing been cultur ed for 3 da ys, some pr otoplast s regenerated cel-l w alls and div ided into tw o cel ls. Six-cell cal lus-like cel-l ma ss wa s also obtained af te r being cultur ed for 6 day s. The se re sult s are g oo d basis f or further culture in large scale. The applica tio n o f marine bacteria on isolat ing vegetat ive cel ls o f these alg a is reported in this pa per.

Abstract:The United Nat ions Co vent ion o n the Law of the Se a entered into for ce on 16 No vember, 1994 and the pr ovi sio ns related to the explor at ion and explo itat io n, co nservat io n and manag ement o f marine liv ing re so ur ces have a lready pro duced and w ill co nt inue to produce grea t impact o n marine f isheries pro duct io n and management . Based on analysis of the prov isions o f the C onvent ion and pr actices o f establishing exclusive eco nomic zo ne and o f implement ing reg ime of the high seas by many co asta l states, it is co ncluded that the develo pment of the f isheries reg ime is in the direct ion o f be nef icia l to co astal states, and that distant w ate r f ishing states have to co operate w ith co astal states and accept the duty a nd responsibility, as the Co nventio n pr ov ides, for the conserv ation of the mar ine liv ing resources, in o rder to ensure the sustainable development of dista nt w ater f isheries. In the light of real ity o f Chinese f isher ies, the demand on manag ement and po ssibility of adverse ef fect s on hig h seas f ishing , af ter the entry into fo rce o f the Conve nt io n, are discussed, and some suggest ions a re made.

Abstract:Based o n the behavio r o f st impson( Tr achypenaeus) and the f ishing methods of st impso n stow net , two new kinds o f stimpson stow net, the hand-knit ted and the cut net s, w ere designed w ith the characterist ics of big sha pe, pr oper st ructur e and impro ved wo rkmanship. The result s of the model test in a tow ing ta nk indicated tha t the dr ag against the cur rent per unit area o f the mo uth o f the ha nd- knit ted net and the cut net is 70%~ 76% and 64%~ 66% of that of the co nvent ional net respect ively . The result s of the compar at ive test s betw ee n the new net s and the o ld one on bo ard dur ing the spring f ishing seaso n in 1993 and 1994 showe d the y ield wa s incr eased by 30. 1% ~ 61. 6% f or the hand-knit ted net and 43. 3% fo r the cut ones. The results of 29 gro ups o f 10 t imes random sampling o f ca tches dur ing tw o years ' ex per iment at sea showed tha t the number o f juv enile stimpson ca ught by the t ria l net s w as reduced by 23. 7% and less f ish w as ca ught , especially the commercial species as compared w ith the co nvent ional net . A special test s on bo ard also show ed tha t the juvenile f ish and shrimp relea sed f rom codend and kept for 18, 30 and 54 hour s wer e mo stly alive. This result pro vided scient if ic informat io n for the techno lo gical inno vat io n on stow net and could be used as refer ence to the impro veme nt on o ther f ilter net s.

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