水库网箱养殖彭泽鲫试验

经过１６个月（含自然越冬期）的网箱养殖，成功地把４．５万尾体长２．５ｃｍ，尾重０．７ｇ的彭泽鲫乌仔，养成平均尾重３４６－４０５ｇ，的商品鱼，成活率为８７％，鱼产量１４９２０ｋｇ，产值２２３８００元，利润８６７７８元，每ｋｇ鱼盈利５．８２元，４ｍ＾３小网箱平均养成单产为１８６．５ｋｇ／ｍ＾３。     

南美白对虾池塘淡水养殖试验

１９９９年在广西水产研究所中试基地进行了南美白对虾池塘淡水养殖试验。在６００ｍ＾２的淡水池塘中投放平均全长２．３５ｃｍ的淡化虾苗２．５万尾，经７０ｄ饲养，生产成虫９８ｋｇ，成虾平均全长５．５９ｃｍ（最大为１０．６ｃｍ），平均体长８．３４ｃｍ（最大为９．４ｃｍ），平均体重７．７３ｇ（最大为１１．５ｇ），养殖成活率为５０．７％。     

影响工厂化养殖牙鲆生长及成活率的因素

近几年，荣成市工厂化牙鲆养殖迅猛发展，截止目前养殖面积已达 １６ ５万 ｍ２，居全国第一，牙鲆鱼的存养量达８００多万尾，并且仍有逐渐增加的势头。荣成市邱家渔业公司现在养鱼面积４万多ｍ２，牙鲆苗从全长 ３～５ ｃｍ养至 ５００ ｇ以上的商品鱼，仅需１６个月，其养殖成活率超过６２％。不论生长速度还是养殖成活率，都达到了国内较先进的水平。现将笔者两年多所获得的有关影响牙鲆工厂化养殖生长及成活的因素介绍如下，以供广大养殖工作者参考。１ 苗 种１．１ 鱼苗质量 鱼苗质量会直接影响整个养殖过程中牙鲆的生长及成活率，购…     

坝基渗流水饲养虹鳟试验报告

本文报告了利用坝基渗水养殖虹鳟的过程和成绩。试验在水温低于１４．２℃，溶氧只有３．５－７．０ｍｇ／１的情况下，经１１７天的饲养，个体净增重２５６ｇ，为鱼种的１．１６倍，群体增重１．１２倍。１＾＋龄鱼种饲养２５６天，个体净增重３６５．４ｇ。中后期成活率为９８％，规格较整齐。每ｍ＾２净产鱼１０．４５ｋｇ。     

南美白对虾淡水池养高产试验

２０００年在广西水产研究所蟹场的两个水泥池进行了南美白对虾淡水池养试验。在１９２ｍ＾２的水池中投放平均全长１．１０ｃｍ的淡化虾苗１．７５万尾，经８０ｄ饲养，生产成虾８８ｋｇ。成虾平均全长９．６３ｃｍ（最大１０．０８ｃｍ），平均体长８．２８ｃｍ（最大为９．５０ｃｍ），平均体重７．８１ｇ（最大为１１．９０ｇ），平均养殖成活率为６４．４％。采用水泥池养殖、淡化后放养、投喂人工合颗粒饲料、调控水质、适时捕     

斑点叉尾hui网箱养殖高产技术研究

进行了斑点叉尾Ｈｕｉ鱼苗池塘强化培育，网箱养成鱼种、鱼种网箱越冬和商品鱼网箱养殖试验。Ｈｕｉ鱼苗网箱培育当年个体重达２２．９８ｇ，网箱越冬成活率９４．２％，网箱养商品Ｈｕｉ净产５１．３ｋｇ／ｍ＾３，个体均重３４１．９ｇ，饲料系数１．７０。     

泥河水库梭鲈池塘养殖技术研究

实验梭鲈鱼苗平均全长３．０ｃｍ，平均体重０．１３ｇ，采取自然繁殖饵料鱼与投喂碎野杂鱼的方法，经１２０ｄ饲养，出塘时平均全长１１．５４ｃｍ，平均体重１１．０ｇ，成活率１００％。肥满度Ｋ＝１．３２，体长与体重的回归方程为：Ｗ＝０．０００１３１９Ｌ＾５．０１７９。本文还讨论了梭鲈在高寒地区水产养殖中的价值。     

坑道养鲍技术研究

利用坑道将海水温度调到鲍的最适生长水温１４－２１℃。结果：鲍能常年生长，养殖２０个月，平均壳长６ｃｍ，体重２６ｇ，成活率９３．４％。在总面积１０００ｍ＾２坑道内，养成鲍１０ｔ，产值３６０万元，创利税２３８万元。     

不同规格的大口鲶苗种池塘培育效果比较

大口鲶主要分布于我国长江干、支流和少数通江湖泊中，属大型的经济鱼类。该鱼生长快、肉味鲜美、广温耐寒 ,但由于该鱼属肉食性鱼类 ,当饵料缺乏或个体大小不整齐时 ,会出现互相残食现象 ,影响鱼种阶段的成活率 ,挫伤了养殖者的积极性。１９９９年５月１２日至６月１２日我们进行了该苗种的养殖试验 ,旨在解决大口鲶苗种培育技术难题。现将试验结果报告如下。１材料与方法１．１试验鱼苗系自繁并经小型水泥池培育７～１５ｄ后的鱼苗 ,全长１５～３５ｃｍ。试验池４口 ,每口面积６６７ ,石砌水泥护坡 ,池底平坦 ,淤泥深５～１０ｃｍ ,水深…     

花尾胡椒鲷Plectorhinchus cinctus（Temmincket Schlegel）早 …

花尾胡椒鲷为底层鱼尖，以觅食底栖动物为主；早期幼鱼经盐度淡化驯养，能适应低盐度咸水池塘饲养。均全长３．５ｃｍ重０．６３ｇ的幼鱼经７４ｄ池塘中间培育，长成均全长１０．９９ｃｍ、重２７．３２ｇ，成活率８７．５％。全长日均增长率１．５５％，与养殖天数的关系式为Ｌ＝３．６５０２ｅ＾０．０１５０ｄ；体重日均增重０．３７ｇ，日均增长率５．０９％，与养殖天数的关系式为Ｗ＝０．７３０３ｅ＾０．０５０４ｄ，全长与体     

Larval Development and Rearing of Longtooth Grouper Epinephelus bruneus in Jeju Island, Korea

Eggs and sperm were obtained from a female (6.3 kg/BW) and a male (8.4 kg/BW) longtooth grouper Epinephelus bruneus following HCG injection in July 2003. The eggs were fertilized artMcially with the sperm and incubated in one of two 50-m³ tanks after washing the fertilized eggs. The fertilized eggs were 830–950 pn (average 900 ± 2 μm) in diameter and the respective fertilization and hatching rates were 97.7 ± 0.6% and 96.8 ± 0.5% at a water temperature of 25.0 ± 0.5 C. With this regime, the survival rate by day 93 was 7.5% in the 50-m³ tank. The elapsed time from hatching to opening the mouth was 3 d at 25 C. The initial mouth size (z) of the larvae was 0.22–0.23 mm. The newly hatched larvae were 2.02 ± 0.02 mm TL; this increased to 4.12 ± 0.09 mm TL by day 11. By day 54, the larvae had metamorphosed into juveniles and reached 41.12 ± 1.20 mm TL, and by day 93 the juveniles reached 93.78 ± 1.98 mm TL. In all, 49.5% of the larvae were malformed and the type of malformation was diverse.     

美洲鲥仔、稚、幼鱼的形态发育与生长特征

通过对美洲鲥(Alosa sapidissima)仔、稚、幼各发育期的连续取样,系统观察了仔、稚、幼各期的形态变化及生长发育特征.结果显示:在水温(20±1)℃下,初孵仔鱼全长(6.75±0.60)mm;2日龄仔鱼即开口摄食,进入混合营养期;4 日龄仔鱼卵黄囊吸收完毕进人晚期仔鱼阶段,完全依靠外源物质获取能量,主要以鳔室、脊椎形成及各鳍的分化与形成为主要标志;培育至36 d,仔鱼鳃盖后缘及脊椎骨两侧线有少量鳞片状突起,标志美洲鲥结束仔鱼期进入稚鱼期;培育至65 d,仔鱼身上鳞片基本长出,腹膜闭合,美洲鲥完成变态成为幼鱼.仔鱼培育期间,除了严格控制培育水温在(20±1)℃外,2日龄仔鱼开口后就应及时投喂轮虫类开口饵料,密度为5～10 ind/mL,这是苗种培育中不可忽视的重要环节.稚鱼期间在主食枝角类、桡足类的同时进行驯食.本实验采用特制缓沉饲料及时驯化转食再过渡到伞部摄食人工浮性膨化颗粒饲料,驯食时间为21 d,驯食是成功进行人工池塘养殖的关键所在.本研究旨在探讨提高美洲鲥早期培育过程中的成活率及成功进行池塘养殖的可行性.     

Behavioral interactions between black mudfish (Neochanna diversus Stokell, 1949: Galaxiidae) and mosquitofish (Gambusia affinis Baird & Girard, 1854)a

The behavior of black mudfish (Neochanna diversus Stokell, 1949: Galaxiidae) and mosquitofish (Gambusia affinis Baird & Girard, 1854: Poeciliidae) was investigated in laboratory tanks. Black mudfish are indigenous to northern New Zealand, and mosquitofish are introduced; both species are sympatric in wetlands in the Waikato region. By comparing position, feeding rates and aggressive behavior of both species, we found that black mudfish were increasingly able to compete with mosquitofish as they grew from fry to adults. Mosquitofish were more aggressive towards mudfish fry and juveniles than were these two life stages towards mosquitofish, but adult mudfish were aggressive towards mosquitofish. Both small (18–24 mm total length (TL)) and large mosquitofish (25–36 mm TL) showed high aggression towards mudfish fry (13–18 mm TL), and fry were eaten by large mosquitofish. However, 3 interspecific differences appear to allow coexistence of these two species. Firstly, mudfish reproduce in winter, whereas mosquitofish reproduce in summer, resulting in mudfish fry being present when mosquitofish are at their lowest abundance. Secondly, mudfish can survive in seasonally dry habitats by aestivation, while mosquitofish cannot. Thirdly, adult black mudfish are nocturnal, whereas mosquitofish are primarily diurnal.     

Preliminary trials on the use of large outdoor tanks for the ongrowing of Octopus maya juveniles

Octopus maya has high growth rates, direct embryonic development and high hatchling survival, making it a good candidate for aquaculture diversification. The present study was designed to evaluate growth rate, survival and food conversion of O. maya juveniles cultured in outdoor tanks. Octopuses were captured from the wild during the fishing season, and fed discarded fish heads and whole crabs. Three trials were conducted between 23 and 32 days, in September (trial 1), October (trial 2) and November (trial 3) where a decrease in sea water temperature was registered (29–24 °C, from September to November respectively). Octopuses were held in three outdoor tanks of 5 m² of bottom area and 0.5 m deep, aerated sea water and water flow allowing 10% of water exchange per day. Initial density was between 2.9 and 3.8 kg m^?3 with different initial mean weight of 542.3 ± 18.8, 493 ± 11.9 and 321 ± 7.8 g, for trials 1, 2 and 3 respectively. Specific growth rate varied between 1.8 and 2.7% BW day^?1 with no apparent relation with the culture temperature. These results put in evidence that tanks used are adequate for the ongrowing of O. maya juveniles, with commercial size being attained in a few weeks.     

Habitat utilization,feeding, and growth of wild spotted halibut <Emphasis Type="Italic">Verasper variegatus</Emphasis> in a shallow brackish lagoon: Matsukawa-ura,northeastern Japan

Habitat utilization, feeding, and growth of a rare pleuronectid flatfish, spotted halibut Verasper variegatus, were examined in a brackish lagoon in northeastern Japan: Matsukawa-ura. The distribution and date–length data of spotted halibut collected mainly from beam-trawl samplings during 1983–2008 indicated that age-0 juveniles [n = 25, 6.0–18.0 cm total length (TL)] and older spotted halibut (n = 71, 13.8–43.0 cm TL) inhabited almost the entire northern part of Matsukawa-ura. Comparative distribution surveys of spotted halibut, stone flounder, and marbled flounder during 1985–1989 revealed similar distribution patterns of these flatfishes; the highest densities were found around the central part of Matsukawa-ura, although significantly lower abundance was detected for spotted halibut. Linear growth equations of age-0 juveniles demonstrated that spotted halibut were able to achieve high growth after June, probably because abundant prey (e.g., mysids and gammarids) and suitable physical conditions (warmer water temperature and lower salinity) were present. The main prey items shifted from various crustaceans including mysids, caridean shrimps, and anomurans to brachyura Hemigrapsus spp. (≥20 cm TL). Our study shows that spotted halibut use the shallow brackish lagoon as an important nursery for juveniles, and also as a feeding ground for young and adults.     

昆明裂腹鱼人工繁殖技术研究

于2003年8月起进行野生昆明裂腹鱼(Schizothorax grahami)亲鱼培育研究,并2009年5月3日—9日进行了人工繁殖技术和鱼苗培育实验。结果显示:野生昆明裂腹鱼在人工驯化养殖条件下,能在池塘内正常生长发育。亲鱼初次性成熟年龄为4龄,雌鱼以5～6龄最佳。采用二次胸鳍基部注射,催产孵化水温为14～17℃,效应时间平均为46h,平均孵化时间为176 h,鱼苗经60 d培育(平均水温14～18℃)体长可达5.05 cm。     

Osmoregulatory ability of chum salmon,Oncorhynchus keta,reared in fresh water for prolonged periods

The osmoregulatory ability of chum salmon (Oncorhynchus keta), reared in fresh water for a prolonged period, was examined by transferring them directly to seawater and then back to fresh water. When fry and juveniles weighing 0.3–125g, reared in fresh water for 1.5–13 months, were transferred directly to seawater, they adjusted their plasma Na⁺ concentration to the seawater-adapted level within 12–24h. When they were transferred back to fresh water after having been adapted to seawater for 2 weeks, the plasma Na⁺ level gradually decreased during the first 12–24h, and then increased to reattain the initial freshwater level after 5–7 days. No mortality was observed during the experiment except among the smallest fry weighing about 0.3g after transfer to seawater (2.1%). The maintenance of good osmoregulatory ability of the chum salmon for a prolonged period in fresh water seems to be unique among Pacific salmon, with the possible exception of the pink salmon.Changes in plasma levels of hormones during the transfer experiments were recorded in juveniles reared in fresh water for 13 months. Prolactin levels increased maximally 3 days after transfer from seawater to fresh water, as would be expected from its well-established role in freshwater adaptation in several euryhaline teleosts. In addition, an increase in plasma growth hormone was observed during the first 12h after seawater transfer, along with a tendency towards a decrease during freshwater transfer, suggesting an important role for this hormone in seawater adaptation. There were no consistent changes in plasma levels of thyroxine and cortisol during freshwater to seawater or seawater to freshwater transfer.     

Extension of nursery culture of Scylla serrata (Forsskål) juveniles in net cages and ponds

To address the preference of mud crab farmers for larger size Scylla serrata juveniles (5.0–10 g body weight or BW; 3.0–5.0 cm internal carapace width or ICW), a study was conducted to compare the growth and survival of crab juveniles (2.0–5.0 g BW; 1.0–3.0 cm ICW) produced a month after stocking of megalopae in net cages when reared further in net cages installed in earthen ponds or when stocked directly in earthen ponds. In a 3 × 2 factorial experiment, three stocking densities (1, 3 and 5 ind m⁻²), two types of rearing units (net cages or earthen pond) were used. Megalopae were grown to juvenile stage for 30 days in net cages set inside a 4000 m² brackishwater pond and fed brown mussel (Modiolus metcalfei). Crab juveniles were then transferred to either net cages (mesh size of 1.0 mm) or earthen ponds at three stocking densities. After 1 month, no interaction between stocking density and rearing unit was detected so data were pooled for each stocking density and rearing unit. There were no significant differences in the growth or survival rate of crab juveniles across stocking density treatments. Regardless of stocking density, survival in net cages was higher (77.11±6.62%) than in ponds (40.41±3.59%). Growth, however, was significantly higher for crab juveniles reared in earthen ponds. The range of mean BW of 10.5–16.0 g and an ICW of 3.78–4.33 cm obtained are within the size range preferred by mud crab operators for stocking grow‐out ponds.     

Effect of diets on growth and reproductive development of juvenile pikeperch, Stizostedion lucioperca (L.), reared under intensive culture conditions

Juvenile pikeperch 3.66 ± 0.23 cm total length (TL) and 0.32 ± 0.05 g were reared in water at 22 ± 0.5^°C and fed with live zooplankton or alternatively a commercial trout feed. Fish fed with dry diet grew faster and had higher condition factor than fish fed live zooplankton. Sex differentiation in pikeperch was visible at different stages of ontogenesis, but was related to the fish growth rate. The gonads offish that were 3.43-5.69 cm TL revealed undifferentiated characteristics. Clear indication of oogenesis in females was observed in pikeperch at 7.9 cm TL and 3.47 g, whereas evident spermatogenesis was not observed till the end of the experiment.     

Comparison of stocking time and density on Gulf Killifish growth in freshwater ponds

The Gulf Killifish (Fundulus grandis) is a popular baitfish and a candidate for commercial‐scale production. For inland production, ponds may need to be stocked at different times and densities to meet market demands. Therefore, in Experiment 1, juveniles were stocked into freshwater ponds at a density of 25,000 fish/ha, with two cohorts (mean total length (TL) = 3.92; 3.52 cm) stocked 1 month apart and evaluated for 12 weeks. Cohort 1 had a lower overall survival (40%) than cohort 2 (79%); with no difference between mean final TL (8.46; 8.00 cm); reaching a market size of 6 cm in 22 days and 32 days respectively. In Experiment 2, juveniles (mean TL = 3.16; 3.23 cm) were stocked into freshwater ponds at two densities (25,000 fish/ha and 50,000 fish/ha). Mean final TL was greater in the lower stocking density (8.68 cm) than the higher stocking density (8.20 cm); with no differences in survival between treatments (75; 72%) respectively. Lower stocking and higher stocking densities reached a market size of 6 cm in 29 and 31 days respectively. These results suggest that multiple cohorts can be stocked and grown to market size in one season at a stocking density of 50,000 fish/ha.