红鳍东方Tun海面网箱养殖若干技术问题

1　生产现状在日本 ,近 2 0年来 ,作为名贵鱼类 ,红鳍东方一直列为重要养殖对象。日本红鳍东方养殖产量已于 1 993年达达 442 7ｔ,与近年一直维持在5 0 0 0ｔ左右。日本红鳍东方养殖主要集中于九州和四国地区 ,养殖红鳍东方主要产地为熊本县、长崎县、鹿儿岛县和爱媛县。在日本 ,红鳍东方养殖一向为海面网箱养殖。在中国 ,近 1 0年来 ,尤其是近几年 ,适应日本和韩国市场需求 ,红鳍东方养殖也已呈现迅猛发展态势。中国养殖红鳍东方对日本出口数量已于 2 0 0 0年达到 3 0 0ｔ左右 ,而于 2 0 0 1年高达7.4ｔ。此外 ,中国养殖红鳍…     

红鳍东方室内水槽越冬健康养殖

1　越冬是红鳍东方养殖重要生产环节在作为我国养殖红鳍东方重要进口国的日本 ,红鳍东方上市规格一般在 60 0 g以上 ,而且 ,规格 1kg以上的大规格红鳍东方备受青睐。一般来说 ,在日本市场 ,1kg左右红鳍东方卖价要比 60 0 g红鳍东方高出 1倍。 2 0 0 2年 ,在大连 ,9     

红鳍东方的健康状态与鱼病诊断

自20世纪90年代起,红鳍东方已逐渐成为我国海水鱼类主要养殖品种,主要出口韩国和日本,取得了良好的经济效益。然而近年来由于水域环境,尤其水质的变化,再加上管理不善,饵料质量不稳定及滥用药物,使得养殖红鳍东方的健康状态恶化,尤其在越冬过程中出现大量死亡。由于养殖过程中乱用药物,出口中被检出抗生素和甲醛类等药物的残留,严重危害养殖红鳍东方的发展,因此掌握红鳍东方的健康状态和鱼病诊断至关重要。1红鳍东方的健康状态诊断健康的红鳍东方其状态可从以下3个外观指标进行粗略判断:一是摄饵状态良好;二是游泳状态良好;三…     

红鳍东方鲀的健康状态与鱼病诊断

自20世纪90年代起,红鳍东方鲀已逐渐成为我国海水鱼类主要养殖品种,主要出口韩国和日本,取得了良好的经济效益.然而近年来由于水域环境,尤其水质的变化,再加上管理不善,饵料质量不稳定及滥用药物,使得养殖红鳍东方鲀的健康状态恶化,尤其在越冬过程中出现大量死亡.由于养殖过程中乱用药物,出口中被检出抗生素和甲醛类等药物的残留,严重危害养殖红鳍东方鲀的发展,因此掌握红鳍东方鲀的健康状态和鱼病诊断至关重要.     

红鳍东方鲀集约化网箱养殖技术

红鳍东方鲀(Fugu rubripes)分布于中国黄海、渤海及日本海域,是鲀科鱼类中可进行养殖的优良品种之一,并已发展成为我国重要的海水养殖精品,全国年成品鱼产量达4000t左右,养殖产量已接近河鲀消费大国日本。红鳍东方鲀大规模集约化网箱养殖是我国近年来新增的养殖模式,它具有养殖成本低、鱼体生长快、鱼肉品质好、养殖管理方便和易于活鱼运输等优点。笔者总结在辽宁大连、山东荣成等地进行红鳍东方鲀的集约化网箱养殖经验,具体结合2002年在山东荣成桑沟湾海区网箱养殖红鳍东方鲀的数据,就集约化网箱养殖红鳍东方鲀技术及体会介绍如下:一、海…     

影响红鳍东方鲀种网箱培育成活率的因素

红鳍东方鲀(Fugu rubripes)俗称黑廷巴,是主要的海水养殖品种之一。红鳍东方鲀鱼种网箱培育是养殖成功的基础。前几年,芝罘湾各养殖单位,鱼种网箱培育成活率不一,低者20％左右,高者达90％以上。 现据本场和周边单位的生产情况,对影响红鳍东方鲀鱼种网箱培育成活率的一些因素浅析如下: 一、鱼种质量 入箱鱼种要求体质健壮,规格整齐,色泽鲜亮,游动活泼,肥满度大,规格大,无畸形。     

红鳍东方鲀海面网箱养殖若干技术问题

1生产现状 在日本,近20年来,作为名贵鱼类,红鳍东方鲀一直列为重要养殖对象.日本红鳍东方鲀养殖产量已于1993年达达4 427 t,与近年一直维持在5000t左右.日本红鳍东方鲀养殖主要集中于九州和四国地区,养殖红鳍东方鲀主要产地为熊本县、长崎县、鹿儿岛县和爱媛县.在日本,红鳍东方鲀养殖一向为海面网箱养殖.     

红鳍东方鲀的人工繁殖试验

采用网箱养殖四年的红鳍东方鲀经过颗粒状的促黄体生成激素释放素(LH-RH)的植埋,促使性腺成熟,再通过注射绒毛膜促性腺激素(HCG)与大麻哈鱼脑垂体混合液诱导排卵,采卵后进行人工授精,得到红鳍东方鲀受精卵,孵化后得到红鳍东方鲀仔鱼。     

土池养殖红鳍东方技术要点

红鳍东方 (Fugurubripes)俗名廷巴鱼 ,是沿海地区养殖的主要品种之一。红鳍东方的养殖是近几年兴起的产业 ,目前各养殖单位或个人在红鳍东方成鱼养殖成活率上高低不等 ,高的达 90 %以上 ,低的只有 5 0 %左右。笔者根据多年的养殖经验 ,就红鳍东方在成鱼养殖上保持成活率达 90 %以上的几个技术要点总结如下 :1　池塘条件池塘面积在 0 .66hm2 ～ 3.33hm2 为宜 ,配备单独的进排水闸各一处 ,每个池配有水泵。池塘要彻底清除污泥 ,特别是多年养殖过的池塘 (旧虾池 ) ,放苗前要严格清除多年积累的腐殖质和硫化氢等有害物质 ,并用消毒药物…     

国外简讯

日本开发河豚养殖新法日本长崎水产中心最近开发了一种养殖红鳍东方纯的新技术。使用该技术,红鳍东方(鱼屯)稚鱼饲养至1公斤以上的二龄鱼,存活率达90%:而用过去的养殖法,这种稚鱼生长至二龄鱼时,成活率不到20%,这是因为在网箱中河豚互相撕咬,造成伤口感染的缘故。该中心推断引起互相撕咬的原因是网箱内的河豚处于紧张状态。因此自     

红鳍东方鲀开口饵料筛选试验

本文选择水产育苗常用的幼体开口饵料──小球藻、轮虫、卤虫幼体、蛋黄对初孵红鳍东方进行开口饵料筛选试验。结果表明：用小球藻和轮虫混合投喂效果最好,其余依次为轮虫、卤虫幼体、蛋黄。     

Effects of water flow velocity and fish culture on net biofouling in fish cages

The effects of water flow, fish feed and cage position on net biofouling was examined in a floating cage fish farm. Fouling of 16 mm mesh net panels suspended inside and outside net cages and exposed to different treatments were monitored weekly until net apertures were completely occluded by the fouling organisms (8 weeks). Results indicate a dramatic reduction in water flow velocity throughout the fish farm due to the cage units themselves and net biofouling. The reduced water flow (<10 cm s^?1) inside net cages promoted rapid net biofouling, while rapid water flow outside the net cages (>25 cm s^?1) kept the net fouling organisms at bay. Although fish rearing in net cages with inputs of commercial pellet feed increased sessile biofouling (222% higher than outside the net cages) and non‐sessile biofouling (570% higher), the type of fish feed used did not significantly affect biofouling development. The study recommends that the geometry of serially arranged net cages, as commonly deployed in tropical tidal estuaries, be reconfigured to improve flow through in order to minimize the impact of fouling.     

A synopsis of smolt production in cages in a coastal freshwater lake in Norway

Abstract. Fish farming activities based on salmonid smolt production in cages were monitored in a coastal freshwater lake in western Norway. Yearly ongrowth in the fish farm increased from 350kg in 1979 to 15150kg in 1985, while maximum biomass of standing stock increased to nearly 14000kg in the same period. Maximum daily mortality observed was 0·37% of total stock in August 1983 due to an Ichthyobodo necator infection.
Except for 1983, between 61 and 73% of annual amount of feed was used in the second half of the year. Total feed amount used in 1979–85 was 77750kg. The phosphorous effluents decreased from 88 to 90% of the feed content to 80·4% in 1984–85.
A set of easily calculated parameters for judging management possibilities and success in cage farming is proposed: annual heat sum; mortality rate; growth rate; feed conversion; and phosphorous retention in fish.     

Efficacy of Sarafloxacin Hydrochloride in Treating Naturally-Induced Edwardsiella ictaluri Infections in Channel Catfish,Ictalurus punctatus

Sarafin (sarafloxacin hydrochloride), a new antibacterial, was evaluated in the field on a naturally induced infection of Edwardsiella ictaluri in channel catfish, -Ictalurus punctatus. Healthy channel catfish (mean weight = 50 g) were stocked into nine cages at 200 fish per cage in a pond with an undergoing E. ictaluri infection. Seven days after stocking, dead fish were observed in the cages with clinical signs of enteric septicemia of channel catfish (ESC). After E. ictaluri was confirmed through isolative biochemical tests, medicated feed was applied for five consecutive days. During this period, fish in three control cages received a commercial 32% protein floating feed, three other cages of fish served as positive controls and were fed Romet, and three cages received the test feed with Sarafin. Both medicated feeds reduced the increase in cumulative percent mortality. In the control cages, cumulative percent mortalities continued to increase throughout the study period. Average daily mortality rates were significantly lower following both treatments of medicated feed, and treatments receiving Sarafin showed the greatest reduction in average daily mortality rates. Average daily mortality rates in the control did not change after the medicated feeding period. Toward the end of the study, temperatures reached 30°C, above the active range of ESC infections, and all mortalities ceased.     

Temporary Sequestration of Fingerling Channel Catfish in Cages as a Means to Improve Production of Multiple-Crop Ponds

Abstract

Two studies were conducted to determine if temporary sequestration of fingerling channel catfish, Ictalurus punctatus, in cages improves production of multiple-crop ponds. In the first study, 0.04-ha ponds were stocked with 295 large (mean weight = 566 g) and 780 fingerling (mean weight = 21 g) catfish. Fingerlings were stocked into cages or open ponds. At 120 days after stocking, fish in cages were released. After an additional 40 days, ponds were clean-harvested to remove large (>500 g) and small (<500 g) fish. In the second study, ponds (0.08-ha) were stocked with 750 large (mean weight = 46 g) and 750 small (mean weight = 20 g) fingerling catfish. Small fingerlings were stocked into cages or open ponds. At 60 days after stocking, fish in cages were released. Market-ready fish were selectively harvested at five and nine months after stocking. Results from the first study indicated that individual weight, weight gain, and yield of both size classes of fish raised in sequestered ponds were significantly greater (P< 0.05) than that of fish raised in open ponds. In addition, total weight gain and yield of fish in sequestered ponds was significantly greater (P< 0.05) than those in non-sequestered ponds. Results from the second study indicated that a significantly greater (P< 0.05) number of market-ready fish were harvested from sequestered ponds than from non-sequestered ponds. Mean yield of sequestered ponds was 31% greater than that of non-sequestered ponds; however, differences were not significant (P> 0.05). Amount of feed fed to fish raised in sequestered ponds was significantly greater (P< 0.05) than amount of feed fed to fish raised in non-sequestered ponds in both studies. It is unclear which factor or factors were responsible for the enhanced production of sequestered ponds; however, temporary sequestration may reduce agonistic behavior and competition for feed between fish size groups.     

Effects of restricted feeding on growth of red sea bream and sedimentation of aquaculture wastes

For improving the economic and environmental sustainability of fish farming, it is necessary to optimize feeding regimes. From this viewpoint, we monitored the growth and mortality of red sea bream (Pagrus major), C and N fluxes and sediment chemistry at 2 commercial fish cages; cage 1 (conventional satiation feeding) and cage 2 (restricted feeding: same feeding frequency but 18% reduction in the feed amount) for 276 days. The similar specific growth rates (0.43% in cage 1 and 0.39% in cage 2) but different feed conversion efficiencies (0.54 in cage 1 and 0.62 in cage 2) and mortality (> 2-times higher in cage 1) between the 2 cages, indicate overfeeding in cage 1 culture. Elemental and stable isotopic analyses of sediment trap materials enabled the quantification of waste feed- and fecal matter-derived organic matter (OM) separately. The results shows that (1) aquaculture-derived OM comprised most of the fish-farm settling OM, excluding the period from January to April, when natural OM often accounted for a half of the bulk OM, (2) there was a difference in the seasonal trend between the fluxes of waste feed and fecal matter, and (3) there were no differences in the percentage compositions and fluxes of waste feed and fecal matter between the 2 cages. The isotopic analysis showed that the waste feed-derived OM in the sediment below cage 2 was 24% less than that below cage 1, suggesting effect of restricted feeding. Determining the relative amount of waste feed and fecal matter in settling and sedimentary OM is an effective method to evaluate the optimum feeding regime.     

海水鱼类网箱养殖水域沉积物有机质的来源甄别

利用稳定碳氮同位素示踪技术,对南沙港网箱养殖水域沉积物中有机质的来源进行了分析研究。结果表明,网箱养殖区(距离网箱边缘100 m范围内)及对照区(距离网箱边缘大于500 m)沉积物的δ13C值分别为(-17.72±1.2)‰和(-12.73±0.38)‰,δ15N分别为(6.44±0.2)‰和(5.61±0.2)‰。网箱养殖区沉积物的有机质来源主要为残饵和鱼类粪便,比例分别占47.70%和27.71%。随着与养殖网箱距离的增加,网箱养殖源有机质(残饵和鱼类粪便之和)的比例降低,变化趋势符合指数方程y=97.167e-0.007 4x(R2=0.848 1),在潮流驱动的沉积物再悬浮及野生鱼类的扰动影响下,网箱养殖源有机质的水平位移可达400 m。鱼类网箱养殖的养殖废物是南沙港水域沉积物有机污染的主要来源。     

鱖鱼人工饲料网箱养殖的生产性试验

本文报告作者近两年在湖北省嘉鱼县和通山县的浅水湖泊、池塘内利用网箱较大规模进行鱖鱼人工饲料驯饲和网箱集约养殖生产性试验的情况。在试验中用1.0～1.4平方米网箱和W91系列鱖鱼配合饲料驯饲2.5～17.5厘米幼鱖4642尾,成功4161尾,驯饲成功率89.6％;用1.4平方米网箱养殖成鱖,养殖76～90天,平均日尾增重0.74～0.85克,每1平方米网箱净产达4.03～6.91公斤,增重速度与活饵鱼网箱养鱖相当;人工饲料系数1.68～1.78,每增1公斤鱖鱼,饲料成本下降一半以上。     

从河鲀鱼精巢中提取DNA-Na的研究

本文首次报道了从河鲀鱼精巢中提取DNA-Na的方法,在对不同的提取方法进行比较的基础上,提出了一条适宜于河鲀鱼精巢的合理提取工艺;由此工艺提取的DNA-Na产品其各项指标均达到了国外同类产品的水平。     

Quality of wild-captured saithe (Pollachius virens L.) fed formulated diets for 8 months

Fish farms may attract wild fish that feed on waste feed from the cages. Saithe, Pollachius virens L., are particularly numerous around salmon cages in northern Europe and may obtain a significant proportion of their diet from waste feed. It has been claimed that these fish are of inferior quality to saithe that feed on natural diets; differences are said to include soft muscle tissue and a different taste. In order to document such changes in quality we performed a feeding experiment. Young wild saithe were collected and fed either a lipid-rich salmon diet or a lean cod diet for 8 months. All fish were individually tagged and growth was monitored throughout the experiment. Parameters related to flesh quality were measured. Diet clearly influenced the growth rate of the fish, and many fish reached a very high hepatosomatic index when fed on a salmon diet. However, many fish had a low feed intake and thus a low rate of growth. There were some differences in skin and muscle colour, pH and in sensory parameters between wild-caught and artificially fed saithe at the end of the experiment. Those fed the cod diet were more similar to wild saithe than those fed the salmon diet.