Abstract:Seasonal variations in rigor morns of several cultured freshwaterfish, bighead, silver carp and grass carp, were studied in this paper. The experimental results showed that the variations were markedly evident. These threespecies of fish stored at 0℃ reached full rigor state after 2 to 16 hrs (mostly 6 to10 hrs) in May to July and in October, but in the months from January to Marchafter 50 to 100 hrs (about 2to 4 days). However,in the months of April and November, the time after death to full rigor beginning were 10 to 60 hrs. It was foundthat a good negative correlation existed between the seasonal temperature of pondwater and the duration of full rigor. The correlation coefficient was - 0.9236 (P0.01). This correlationship showed that the duration of rigor morns was dependent on the temperature of pond water where the fish cultured. Rigor mornsalso varied with different physiological states before death. The duration of rigormorns of bighead killed alive was much longer than that of fish dead after struggling. The difference of the duration of rigor morns between the species of fishwas not so evident. Therefore, besides distributing of live fish a new distributionway of cultured freshwater fish was suggested,namely the fish killed alive mightbe handled and distributed with ice or without ice stored if the seasonal temperature was less than 10℃,and within a longer time than that for distributing of livefish. The quality criteria and freshness index for freshwater fish were also discussed in the paper.

Abstract:Morphological development of feeding organ of Oreochromis niloticusvarying from 6. 0 mm to 223. 0 mm in total length (n271) was observed throughdissection, sectioning, light and scanning electron microscopy. The followingsubjects were described:1. Development characteristics of gill rakers, buccal palatine, jaw teeth, andpharyngeal teeth;2. Changes in quantitative traits of feeding organ with development, i. e.mouth size (opening),number, density,and length of gill raker, distance betweenthe adjacent gill rakers, number, density and length of lateral protuberances onfiltering lamellae,and distance between lateral protuberances.The following quegtions were also discussed:1. Relationship between feeding mode and feeding function in Tilapia;2. Relationship between development of feeding organ and transition of feeding mode;3. Relationship between changes in quantitative characters of feeding organsand transition of the size-suitability and composition of food:4. Relationship between development of feeding organs and biological technique for Tilapia culture.

Abstract:《中国乡镇企业信息》半月刊中国唯一的以实用技术信息为重点的综合性信息半月刊。《中国乡镇企业信息》由中国乡镇企业协会、中国农学会情报分会、农业部情报所主办。1992年创办，深受各界欢迎，被誉为乡镇企业的科技靠山。

Abstract:A study has been conducted on the maturation of ovary,spawningtype,ages of maturity，spawning waters and hermaphroditism of Lateolabtax japo-nicus (Cuvier et Valoncinnes?.The course of ovarian maturation is divided into sigstages and a recovered stage VI-IV' or IV'. Stage 1-Juveniles，stage II-includingimmature and recovered ovaries;stage III-ripening ovaries;stage IV-nearly ripe ovaries;stage V-ripe ovaries;stage VI-spent ovaries. After the fish releasesd thefirst batch of eggs,the ovaries regenerate into stage VI-IV' (or IV'),which conti-nue to develop rapidly into stage V'. About half a month later the ovaries developinto stage V'. If enviromental conditions are appropriate，then the another spawnmay take place. This fish are released two batches in a breeding season. The ova-ties develop to stage III in October as the age at first maturity，stage IV in Novem-fiber. The mature fish spawn at the middle of November and continue to Januaryof the next year. The fish spawn in the waters of the Yangtze River estuary andits adjacency with higher salinity nearby marine water. The salinity is about 22-26‰.The female and male reach the first maturity at 4 ages and 2 ages in yearold respectively. The individual absolute fecundity ranges from 3几2928-2211000eggs，averaging 1282327 eggs，and the individual relative fecundity ranges fronn185.27-847.71 eggs，averaging 408.03 eggs.

Abstract:The suitable soybean ca,l;e as a substitute for partial fish meal informulated diets for the Chinese mitten-handed crab,Eriocheir sinensis, was studi-ed. The tested material was purified diet consisting of different contents ofsoybean cake, fish meal and maize flour, etc. The tested diets were divided intofive groups containing 36 .64-37.2300 of protein, 2.75-3.10% of lipid and452.51-462.23 KCaI/kg of energy，and animal-vegetable protein ratio was1:0.13-2.43. The experiment results indicated that 30% soybean cake as a sub-stitute for partial fish meal in formulated diets for the crab juvenile was suit-able, taking the essential amino acids of the diets，specific growth rate, proteinutilization ratio and the nutrional composition of the crab，etc, as evalution indicesafter 40 days feeding experiment at 24士10C. The insufficient or excessive soybeancake content in diets caused the essential amino acids' imbalance and decreasedthe growth rate of the crab.

Abstract:This paper describes an epizootic septicemia of Penaeus chinensisinfected by Aero-moms hydrophila and A. caviae. The bacteria were gram negative,short rods with a single polar flagellum，resistant to O/129，no salt requirement,not growth on TCBS,ogidase and catalase positive. Gas was produced from fructose,mannitol,galactose and melibiose, but not from sucrose, maltose and starch. Thebacteria did not ferment lactose,inositol,sorbitol，aylose and trehalose dighdrate,arginine dighdrolase and tryptophan deaminase positive. Production gas fromglucose,V-P reaction,citrate utilization and sulfide production were all positive forA.hydrophila but not for A. caviae.

Abstract:This paper deals with the embryonic development of A. gigas. Theembryonic development stages were discontinuously observed because of the egg-ca.psure. The mathod was the fixadate collected specimen and the egg-capsurebroken into spieces to draw out the embryo. In atmospheric temperature at 25土10C,the embryonic development took 274 hours and the length of embryo increased22 times. According to the external morphology,whole developmental course of theembryo can be divided into7 periods as follows:1 .Cleavage period In the early period cleavage follows the spiral molluscan pattern.The polar bodies mark the animal pole of the egg?2 .Blastula Period There is no morpholgycially dletinct ,but the blastula cayity cari been sean on the sectjceng epacimen 3 .Gastrula period Gastrula can be divided into the earlier stage,middle stageand last stage,but passed epiboly and invagination. 4 .Trochophore larva period The time is of short duration. The embryo hasapical,metatroch and telotroch. 5. Veliger larva period Nifty-two hours later the embryo has become a veli-ger larva with veliger area. The foot is bilobed, the larval shell has begun to besecreted. The adult tentacle primordia appear. 6. Juvenile snail form period The foot can move, eye primordia appear，theshell covers the body or visceral mass. The time is 60% of the embryonic develop-went. 7 .Hatching Just hatching juvenile snail has two whorl. The larval livercells appear to be red.

Abstract:This paper deals with the data of file fish yield(aboat 182000 tons)belonged to Marine Fisheries Corporation of Jiangsu Province from 1974 to 1989 inthe East Ohina Sea. In order to analyze their distributions, it was relative to thewater temperature of fishing grounds. The distributions of the fish Stocks havebeen discussed as well and the results are summarized as follows.1. During the winter season,in this widely regional sea the distribution of thefilefish exists obviously geographical differences.2. There are three local stocks in the East China Sea,namely,the East ChinaSea stock, Yellow Sea stock and the stock belonged to Sea of Japan.3. The fishing features of the East China Sea stock reflected the changes ofthe compositional strueture among the annual catches. In the 1970's the surpluscolony was the main part of the catch composition, and in the late of 1980's the recruit colony was the major part of the catch component.4. The adjacent waters of Diaoyu Dao Island is the spawning ground of the fishfor East China Sea stock. The protection measures for this spawning ground arethe task of top priority.

Abstract:山东近海鳗鱼(Engraulis JaPannicus)资源非常丰富，每年4至9月份，大量产卵亲体和幼鱼遍布沿岸水域;冬季在烟威渔场深水区有越冬群体分布，密度较大。因此，山东省开发利用近海鳗鱼资源具有得天独厚的自然条件。近几年随着传统经济鱼类资源的下降，拖网渔业生产处于困境。特别是养殖业的迅速发展，饵料所需动物蛋白急增，作为鱼粉及鱼油重要原料的鳗鱼资源更待及早开发。开发鳗鱼资源不仅能大幅度增加海洋鱼类产量，而且可将目前过大的捕捞力量转向鳗鱼捕捞，从而减轻对传统经济鱼类及其幼鱼捕捞的压力，有利于鱼类资源的繁殖保护。

Abstract:斑节对虾是东南亚国家最普遍养殖、生长最快的种类。池塘养殖时，3cm长的虾苗经5个月可长到币，?1oog(密度5000 ind/ha)。同时它也是世界上最大的对虾之一，体长可达374mm，有重要的商业销鲁市场价值。

Abstract:光合细菌是一种能以光作为能源，以二氧化碳和有机物作为光合作用的供氢体，兼碳源而营养繁殖的微生物。它广泛分布于水陆环境中，在厌氧弱光条件下具有分解低分子有机物和同化水中氨氮等作用，故有净化水质的显著功效。同时，光合细菌体内含有丰富蛋白质、多种维生素和许多生物活性物质，是鱼、虾、贝幼体的良好饵料。据有关报导，光合细菌对鱼类具有明显的促生长作用和防治鱼虾疾病、净化养殖水质等多方面的功能[张道南等，1988)。早在20年前日本就开展了光合细菌的应用性及生产性研究。在我国台湾省，80年代初该菌也广泛应用于水产养殖业上。

Abstract:体外诱导鱼类卵母细胞成熟技术是指在离体情况下，用诱导物质将处于IV时相的鱼类卵母细胞诱导发育至V时相的技术。此项研究在国外始于七十年代初期，已对十几种鱼作过研究，其中的绝大部分尽止于探家体外诱导鱼类卵母细胞胚泡破裂的最佳条件〔Epler P., 1981; Epler, P., 1986; Gootz, F.W., 1983; Hirose, K., 19,'1; Hirohiko kagawa等，1984; Jalabert, B., 1976; Saat, T. Y., 1976]，而对诱导胚泡破裂后卵母细胞的发育和离体卵母细胞内部结构变化的细胞学观察却少见报导。因此，体外诱导过程中朔母细胞能否正常发育仍缺乏充分的证据。

Abstract:组织病理研究是弄清寄生虫致病机理的重要途径之一。内变形虫属Entamoeba中的不少种类是致病寄生虫，有关它们在人和其它脊椎动物中引起疾病的组织病理已有报道[ Albach和Booden'1978; Schmidt和Roberts, 1981.但在鱼类中，仅见陈启妻[195b浓描述寄生于草鱼肠道中的院内变形虫时，提到该变形虫可穿入寄主的肠粘膜细胞。此外，未见这方面的报道。作者在南方鳍幼鱼肠道中发现了一种内变形虫Entamoeba sp.,对仑引起的肠组织损伤进行了组织切片观察。这对弄清其致病机理是有意义的。

Abstract:红罗非鱼(T, nilotica)x (T. mossambica)(早)是近年来引进的一种高产优良养殖鱼类，是妒形目(Percif ormes)鲡鱼科(Cichidae)罗非鱼属(Tilapia)内种间杂交选育出的新品种。由于其体形及体色酷似海中真绸(Pagrosomus，major)，且肉质鲜美，在太平洋地区有较大市场潜力，在东南亚一带也颇受欢迎，是一个十分具有推广前景的品种。它和莫桑比克罗非鱼(T. mossambica)以及尼罗罗非鱼(T. nilotica)等一样，具有雄鱼生长快于雌鱼、性成熟周期短、繁殖力强导致繁殖过剩影响商品鱼规格等特点。

Abstract:鱼类对某种饵料的嗜好程度，是由饵料中含有的摄饵促进物质状况而定。而鱼类对摄饵促进物质的效应与作用，是通过鱼类的视觉和化学感受器(嗅觉及味觉)来实现。冯昭信等[1979]、赵传细等[1989]、卡尔〔1989年中译本]指出，栖息于水域中的大部分鱼类，其视觉能感受颜色的刺激，可根据光的明暗程度和颜色来区别物体，亦能看到岸上的物体。嗅觉能接受水体中低浓度化学物质的刺激，有感受气味的能力，能区别化学物质且极灵敏。