Survival and growth of the sea cucumber Holothuria leucospilota Brandt: a comparison between suspended and bottom cultures in a subtropical fish farm during summer

The feasibility of co‐culturing the sea cucumber Holothuria leucospilota Brandt in a subtropical fish farm was investigated in a field study. Sea cucumbers were cultured in the fish farm in cages suspended at 4 m deep (suspended culture) and directly on the seafloor (bottom culture). The survival and growth of the sea cucumbers were monitored twice during the 3‐month, summer experimental period (May 26–August 14, 2010). Results showed that the suspension‐cultured sea cucumbers exhibited excellent survival rate (100%) during the whole study period. There also occurred no mortality in the bottom‐cultured sea cucumbers during the first culture period (May 26–July 13); but all these died from anoxia caused by water column stratification during the second culture period (July 14–August 14). The specific growth rate of the bottom‐cultured sea cucumbers (1.05 ± 0.21 % day^?1) was nearly double that of the suspended culture animals (0.57 ± 0.21 % day^?1) during the first culture period, and the growth rates of the suspended culture sea cucumbers in the second culture periods (0.46 ± 0.24 % day^?1) was only a little lower than that of the first period. The sea cucumbers H. leucospilota could ingest and assimilate sediment with high organic matter content with an average assimilation efficiency of 14.9 ± 3.9%. This study indicated that fish farm detritus can be effectively used as a food source for the sea cucumber and that it can be turned into a valuable secondary crop in the form of the sea cucumber biomass.     

Stage-specific distribution of Japanese sea cucumber <Emphasis Type="Italic">Apostichopus japonicus</Emphasis> in Maizuru Bay,Sea of Japan,in relation to environmental factors

The Japanese sea cucumber Apostichopus japonicus plays important ecological and economic roles in the coastal areas of Japan. Here, we aim to reveal the relation between habitat characteristics and density of juvenile and adult sea cucumbers in Maizuru Bay. Density of adult sea cucumbers was estimated by underwater visual surveys and bottom trawls and that of newly settled individuals by seedling collectors distributed in the bay. The physical environment of the sea bottom was evaluated from median diameter, total organic carbon, total nitrogen, carbon-to-nitrogen ratio, carbon isotope ratio, nitrogen isotope ratio, depth, slope, and distance from the coastline. Adult sea cucumber density was higher in the east side than the west side of Maizuru Bay, the former having a no-take zone for sea cucumbers. Juvenile sea cucumbers were most abundantly collected in the central part of the bay. High organic matter from the sea, short distance from the coastline, and high seabed gradient (steepness) had a positive effect on the density of adult sea cucumbers, and depth had positive effects on their body size. We suggest that sustainable management of sea cucumbers can be achieved by a combination of the establishment of no-take zones and increased protection of nursery habitats.     

Otolith microstructure of chum salmon <Emphasis Type="Italic">Oncorhynchus keta</Emphasis>: formation of sea entry check and daily deposition of otolith increments in seawater conditions

To apply otolith microstructure to examination of age and growth of juvenile chum salmon Oncorhynchus keta inhabiting coastal waters, formation of otolith increments was investigated for juveniles reared in a seawater aquarium and in net pens. In all otoliths examined, a distinctive check was formed at the time of sea entry of the fish. The deposition of otolith increments after the check was daily for rearing both in the aquarium (57 days) and in the net pens (26 days). Check formation associated with sea entry was also observed in otoliths of juvenile salmon collected 1 km off the coast of Shari, Hokkaido, Japan. Transmitted light observation of otoliths of those fish revealed a transition in otolith increment appearance from dark to light. Otolith Sr: Ca ratio remarkably changed from a low to a high level, coinciding with the transition in otolith appearance. It is suggested that the transition was associated with individual sea entry. This study demonstrated that the check and/or transition associated with sea entry are applicable to a benchmark for otolith increment counts of juvenile chum salmon inhabiting coastal waters.     

A successful vaccination of Atlantic salmon, Salmo salar L., against 'Hitra disease' or coldwater vibriosis

Abstract. A Vibrio sp. causing the so-called 'Hitra disease' or coldwater vibriosis affecting brood stock Atlantic salmon, Salmo salar L., in Norway, is described by serotyping. Bacteria collected from moribund Atlantic salmon affected by 'Hitra disease' in various parts of Norway, were shown to represent a homogeneous group of marine vibrio. A formalized bacterin was made from one isolate. Vaccination of Atlantic salmon parr was carried out by direct immersion in a formalized bacterin prepared from a Vibrio sp. associated with 'Hitra-disease.' After 6 weeks the fish were revaccinated and transferred to net pens in the sea. Compared with unvaccinated controls, vaccinated fish demonstrated excellent protection when challenged 6 months later during a natural outbreak of coldwater vibriosis.     

Seasonal fluctuations in the flux of particulate organic matter discharged from net pens for fish farming

ABSTRACT:   Fish farming using net pens consumes large amounts of food for the reared fish, resulting in organic enrichment of the sediment below the fish farm from organic discharge in the forms of fish feces and food residues. Sediment traps were set at a net pen within and outside a fish farm, and organic flux on the sea floor was compared. The year-mean organic flux to the sea floor caused by fish farming from September 2003 to September 2004 was estimated at 2.11 gC/m²/day in total organic carbon (TOC) and 0.26 gN/m²/day in total nitrogen (TN), which were 2.5 times (TOC flux) and 2.2 times (TN flux) larger than that for natural organic flux outside the fish farm. The seasonal fluctuation patterns of organic flux to the sea floor below the fish farm did not necessarily coincide with those for the amount of food spent for the fish farming. The largest organic flux to the sea floor occurred in the autumn, when the vertical mixing of the water had just started. Therefore, organic enrichment of the sediment on the sea floor of a fish farm proceeded during this season.     

刺参与红鳍东方鲀的生态混养效果

为了丰富海参池塘养殖的混养种类,实验对刺参和红鳍东方鲀的生态混养效果进行了研究。结果显示,经过100 d的混养实验,红鳍东方鲀平均日增重率为1.07 g/d,特定生长率为4.06%/d,混养组与单养组红鳍东方鲀没有显著差异;但混养条件下刺参的生长状况显著优于单养条件下刺参的生长状况。与红鳍东方鲀混养组刺参平均日增重率为(0.11±0.04)g/d,特定生长率为(0.67±0.20)%/d。单养组刺参平均日增重率为(0.04±0.02)g/d,特定生长率为(0.35±0.19)%/d。研究表明,刺参池塘混养红鳍东方鲀模式下,红鳍东方鲀在正常快速生长的同时,可以有效促进刺参的生长,研究结果可以为刺参池塘的生态复合养殖提供参考依据。     

玉足海参与凡纳滨对虾的混养效果

在室内条件下进行了玉足海参与凡纳滨对虾的混养实验,分析了单养与混养两种条件下养殖水体营养盐结构以及底质成分的变化,测定了对虾与海参的存活率与生长性能。结果显示,混养海参可以明显改变养殖系统的营养盐结构,可使水体中的磷酸盐和硝酸盐浓度有所升高,同时也可有效地控制系统中氨氮浓度。混养海参也可以大幅度地降低沉积物中有机质和硫化物含量,实验结束时混养组硫化物含量为(7.71±1.33)mg/kg,仅相当于单养组浓度的1/3。混养海参对对虾生长及存活具有明显的促进作用,其中混养组对虾体长特异增长率为(0.69±0.13)%/d,显著优于单养组(0.45±0.06)%/d;混养组对虾成活率可达72.5%±22.9%,显著高于对照组55.0%±17.5%。在混养系统内,对虾不会对海参的生存造成负面影响,海参能够有效地选择摄食和利用沉积物中的营养物质(对食物中有机质的同化率可达36.36%±13.79%),并以较快的速度生长。结果表明,在对虾养殖系统中混养玉足海参具有明显的环境与经济效益。本研究可为我国海水养殖业的可持续发展提供一定的科学依据。     

单一或二元的凡纳滨对虾新鲜养殖废物用于花刺参养殖的研究

评估了单一或二元的新鲜凡纳滨对虾（Litopenaeus vannamei）养殖废物用于花刺参（Stichopus monotuberculatus）养殖的可行性,并研究了其对花刺参成活率、特定生长率、排粪率、排氨氮、排亚硝酸盐、粪便中总有机物（TOM）质量分数相比对应的饲料中总有机物质量分数变化的影响。摄食含80%露天养虾废物和20%室内养虾废物的饲料的花刺参生长最快。在同一处理组中,花刺参的夜间排粪率显著高于昼间排粪率（P〈0.05）。花刺参最高和最低的平均总排粪率分别出现在E（20%露天养虾废物和80%室内养虾废物） 和A（露天养虾废物） 处理组。随着不同饲料中粗蛋白水平的降低,花刺参的平均氨氮生产量和亚硝酸盐生产量逐渐降低。随着不同饲料中w（TOM）的降低,不同处理组花刺参排出的粪便中w（TOM）先升高后降低。在每一个处理组中,花刺参排出的粪便中w（TOM）与对应的饲料中w（TOM）相比,都有不同程度的降低,显示花刺参具有降低养虾废物有机污染的潜能。     

Sea cucumber habitat differentiation and site retention as determined by intraspecific stable isotope variation

Stable carbon and nitrogen isotope ratios (δ¹³C/δ¹⁵N) were assessed as a means to ascertain the recent in situ feeding history of the common New Zealand sea cucumber Australostichopus mollis in relation to nutrient enrichment from a longline green‐lipped mussel (Perna canaliculus) farm in Northern New Zealand. δ¹³C and δ¹⁵N isotopic signatures and the ratios of sea cucumbers sampled from within the impact footprint of the mussel farm were compared with those of sea cucumbers residing on adjacent natural reefs. Sea cucumbers from beneath mussel farming longlines had significantly different δ¹³C stable isotope signatures in comparison with sea cucumbers collected from neighbouring natural reef habitats. This difference supports the hypothesis that sea cucumbers in the same bay maintain distinctly different feeding histories, with those residing beneath mussel farming longlines deriving tissue carbon from sediment impacted by farming activities. This hypothesis is further supported by the finding that the isotope signature of sediment collected from beneath the mussel farm is consistent with the expectation that sea cucumbers were feeding on and consuming sediment enriched with bivalve waste (faeces and pseudo‐faeces). In contrast, the nitrogen stable isotope signature (δ¹⁵N) was found to be similar between sites for both sea cucumbers and assumed food sources. Both findings lend support to the viability of future sea cucumber/green‐lipped mussel farm polyculture systems. Sea cucumbers in different locations (mussel farm, natural reef) possessed distinctly different isotope signatures, suggesting that mixing of sea ranched sea cucumbers with natural reef populations would be negligible or non‐existent. Similarities between the isotope signatures in low metabolic tissue of sea cucumbers residing at the mussel farm site to that of mussel farm‐impacted sediment suggest that cucumbers beneath mussel farms appear to have high rates of retention at the farm site.     

Beneficial co‐culture of jellyfish Rhopilema esculenta (Kishinouye) and sea cucumber Apostichopus japonicus (Selenka): implications for pelagic‐benthic coupling

This study investigated monthly changes of sedimentation and sediment properties in three different culture systems (ponds) – i.e. jellyfish Rhopilema esculenta monoculture (J), sea cucumber Apostichopus japonicus and jellyfish co‐culture (SJ) and sea cucumber monoculture (S) – to verify the feasibility of co‐culturing jellyfish and sea cucumbers. Results showed that jellyfish culture accelerated the settling velocity of total particulate matter (TPM). Average TPM settling velocities in the SJ (75.6 g m^?2 day^?1) and J (71.1 g m^?2 day^?1) ponds were significantly higher than that in the S pond (21.7 g m^?2 day^?1) from June to September during the jellyfish culture period. Average settling velocities of organic matter (OM), total organic carbon (TOC), total nitrogen (TN) and total phosphorus (TP) in the SJ pond increased significantly by 3.0, 2.9, 3.3 and 3.8 times, respectively, compared with those in the S pond. Sediment contents of OM, TOC, TN and TP in the SJ and J ponds were significantly higher than those in the S pond during the jellyfish culture season. The specific growth rate of sea cucumbers feeding on SJ sediment was significantly higher than that of those feeding on S sediment. Co‐culturing sea cucumbers with jellyfish may help alleviate benthic nutrient loading due to the jellyfish and provide a secondary cash crop.     

青、白刺参(Apostichopus japonicus)体壁营养成分的比较分析

通过对相同养殖环境条件下,青、白刺参(Apostichopus japonicus)体壁中营养成分(粗蛋白、粗脂肪、多糖、脂肪酸、氨基酸、微量元素等)的测定,比较两种剌参的营养品质与价值.结果显示,青、白刺参的出皮率,体壁中的水分、多糖和灰分含量差异显著(P＜0.05),粗蛋白和粗脂肪差异不显著(P＞0.05).青、白刺参体壁中均检测出20种主要脂肪酸,脂肪酸总量和多不饱和脂肪酸(PUFA)的含量差异不显著(P＞0.05),而青刺参饱和脂肪酸(SFA)含量显著高于白刺参,单不饱和脂肪酸(MUFA)含量显著低于白刺参(P＜0.05).MUFA中青刺参的花生四烯酸(AA)和二十二碳六烯酸(DHA)含量均显著低于白刺参(P＜0.05).青、白刺参体壁中检测出17种氨基酸,必需氨基酸(EAA)、鲜味氨基酸(FAA)和药效氨基酸(DAA)的含量均无显著差异(P＞0.05).青刺参体壁中天冬氨酸和精氨酸含量均显著低于白刺参(P＜0.05).青刺参体壁中Mn和Cr的含量显著低于白刺参(P＜0.05).重金属元素Pb、Cd、Hg、As的含量均符合相关食品卫生标准.综合评价认为,相同养殖环境条件下,白刺参的出皮率、多糖含量、脂肪酸中不饱和脂肪酸含量、AA和DHA的相对百分含量、氨基酸中天冬氨酸和精氨酸含量以及微量元素中Mn和Cr含量均优于青刺参.     

国内外海参养殖技术研究概况

由于海参具有很高的营养价值和药用价值,被人们视为重要的海珍品,因而具有较高的经济价值。近年来,海参消费需求量的逐年增加导致了世界范围内海参自然资源的过度开发和种群数量的急剧下降,因此,海参的人工养殖也随之发展起来。本文对现阶段国内外海参养殖技术的研究现状进行介绍,以期为海参养殖提供理论依据。     

Interactions between South American sea lions Otaria flavescens (Shaw) and salmon farms in southern Chile

By means of surveys in 48 salmon farms in Chile, and the analysis of fish mortality in 23, the results showed that attacks by the South American sea lion, Otaria flavescens, were periodical at a daily and seasonal scale, and because of their natural nocturnal feeding behaviour, were more frequent at night and in fall–winter seasons. The attacks varied markedly between the farms studied. No relation was found between the intensity of attacks, the distance to the nearest colony of sea lions and the population in the colony. Differences found between farms could be because of the different protective devices used, namely anti‐predator nets, acoustic harassment devices (AHDs) and fibreglass models of killer whales, and the way in which they were used. Of these devices, only the anti‐predator net achieved a permanent reduction in sea lion attacks. Both AHDs and fibreglass killer whales were inefficient in the short term.     

渔用防污材料的研究进展及其在渔业上的应用#br#

海洋生物污损给渔业资源的开发与利用等带来诸多问题,因此,研发应用绿色、长效、经济的渔用防污材料非常重要。主要概述了防污涂料、防污功能金属网衣和复合型防污材料3种渔用防污材料的性能、研究进展及其在渔业上的应用情况,分析了渔用防污材料的防污机理与发展前景,可为高性能渔用防污材料的研发提供参考。     

Preliminary Study of the Dietary α‐Tocopherol Requirement in Sea Cucumber,Apostichopus japonicus

This study was conducted to evaluate the dietary α‐tocopherol (vitamin E) requirement in juvenile sea cucumber, Apostichopus japonicus. Sea cucumbers averaging 1.48 ± 0.07 g (mean ± SD) were randomly distributed into 18 rectangular plastic tanks of 20 L capacity in a recirculating system (20 animals per tank). Six semi‐purified experimental diets with average protein and crude lipid levels (dry matter) of 29.7 ± 0.36% and 4.39 ± 0.23% (mean ± SD), respectively were formulated to contain 0 (E4), 15 (E12), 30 (E23), 60 (E44), 120 (E77) and 600 (E378) mg α‐tocopherol/kg diet, supplied as dl‐α‐tocopheryl acetate. Diets were analyzed for α‐tocopherol content by HPLC and the α‐tocopherol levels were 4.01, 12.4, 23.1, 44.3, 77.4 and 378 mg α‐tocopherol/kg diet for E4, E12, E23, E44, E77 and E378 diets, respectively. Casein and defatted fish meal were used as the protein sources in the diets while wheat flour was the carbohydrate source. Sea cucumbers were fed each of the six experimental diets in triplicate groups. At the end of the 14‐week feeding trial, weight gain (WG), specific growth rate (SGR) and feed efficiency (FE) of sea cucumbers fed on E23, E44, E77 and E378 diets were significantly (P < 0.05) higher than those of animals fed on E4 and E12 diets. However, there were no significant differences in WG, SGR and FE among sea cucumbers fed on E23, E44, E77 and E378 diets or among those fed on E4 and E12 diets. Survival of sea cucumbers fed on E44, E77 and E378 diets were significantly higher than those of animals fed on E4, E12 and E23 diets. However, there were no significant differences among sea cucumbers fed on E4, E12 and E23 diets or among those fed on E44 and E77 diets. Whole‐body vitamin E concentration increased with α‐tocopherol content of the diets. Broken line analysis of WG showed an optimum dietary α‐tocopherol requirement of 41 mg α‐tocopherol/kg diet in sea cucumber. These results indicated that the optimum dietary α‐tocopherol requirement in sea cucumber in the form of dl‐α‐tocopheryl acetate could be higher than 23.1 mg α‐tocopherol/kg diet but lower than 44 mg α‐tocopherol/kg diet.     

Influence of diet on growth,reproduction and lipid and fatty acid composition in the sea cucumber Cucumaria frondosa

The suspension‐feeding sea cucumber Cucumaria frondosa is widely distributed in cold waters and is commercially exploited in the North Atlantic. While the species is considered to have potential for aquaculture, its feeding and reproductive biology differs markedly from that of currently cultivated sea cucumbers. Here, for the first time, the influence of food sources on the condition of C. frondosa was experimentally tested. Individuals were fed with either diatoms or fish eggs for 3 months. Specific growth rate (SGR), organ indices, fecundity, gonad maturity and profiles of lipids and fatty acids (FA) in tissues were compared among treatments and with sea cucumbers collected from the field. Individuals fed with fish eggs showed higher SGR and organ indices than all other treatments. The highest proportion of large oocytes was also found in gonad tubules of females from the fish egg treatment, although individuals fed with diatoms were the only ones in which spontaneous spawning occurred. Moreover, gonad and muscle tissues of sea cucumbers from the fish egg treatment presented the highest levels of lipids and essential FA. In contrast, non‐fed sea cucumbers showed negative SGR, relatively low female fecundity and low concentrations of lipids and FA in tissues. While the fish egg diet presented several obvious benefits, phytoplankton remains an important source of carotenoids, which are vital for vitellogenesis in echinoderms. This indicates that mixed diets rich in lipids, essential FA and carotenoids can be further investigated to optimize growth and reproductive output of this species in captivity.     

Catch me if you can: How to recapture lumpfish using light as an attractant

The use of lumpfish in salmon farming allows the removal of sea lice all year round, without the use of chemicals or mechanical treatments. In Norway alone, around 31 million lumpfish are currently put into sea pens whereas no efficient method to re-catch these fish once they no longer are efficient salmon lice grazers (from 300 g) exists. At present, collecting lumpfish in sea-cages is a labour- and time-consuming process and, if these fish are to be harvested, an efficient method for collecting lumpfish is urgently needed. In this study, we tested coloured light as an attractant to lure lumpfish into passive traps (pods). Three small-scale pilot experiments both demonstrated the highest re-capture rate when a blue light-source was used, whereas red and yellow light gave the lowest re-capture rate. A subsequent large-scale trial failed to demonstrate significant re-catch of lumpfish. It is concluded that although blue light clearly attracted lumpfish in laboratory trials, further studies are needed in order to exploit this attribute commercially.     

Effects of Jerusalem artichoke powder on the growth performance,nonspecific immunity,and gastrointestinal microbiota of sea cucumber

This study investigated how Jerusalem artichoke powder (JAP) affected the growth, immunity, and gut microbiota of the sea cucumber, Apostichopus japonicus Selenka. Animals were fed diets containing antibiotic (1 ppm) or five levels of JAP (0, 2.5, 5, 10, and 15 g/kg). After the feeding trial, three sea cucumbers were sampled per tank to assay for immunity and gut microbiota composition. Dietary supplementation of 2.5 g/kg JAP significantly improved the growth rate and phenoloxidase activity of sea cucumbers. The diet containing 5 g/kg of JAP increased the survival rate and phagocytic activity, and the diet containing 15 g/kg of JAP increased the growth rate and total coelomocyte count of sea cucumbers. Moreover, exposure to antibiotics significantly changed the microbiota of sea cucumbers, while the JAP supplementation stimulated the development of microbiota communities, which could be more homogeneous. Supplementing the diets with 15 g/kg of JAP increased the growth of Rhodobacterales, and this may underlie the higher growth rate of sea cucumbers in this treatment. Considered together, our results suggest that supplementing the diet of sea cucumber with JAP may be beneficial for nonantibiotic farming of sea cucumber.     

The Effect of Diet on the Energy Budget of the Brown Sea Cucumber,Stichopus mollis (Hutton)

This study investigated the ability of the brown sea cucumber, Stichopus (Australostichopus) mollis, to grow on diets made from aquaculture waste. Weight‐standardized rates (ingestion, assimilation, respiration, ammonia excretion, and fecal excretion) of small (juvenile), medium (mature), and large (mature) sea cucumbers were measured and energy budgets constructed to quantify their growth rates when offered three different diets at 14, 16, and 18 C. Three types of diet were offered: uneaten abalone food (diet A) and two types of abalone feces, one where abalone were fed 50% Macrocystis pyrifera and 50% Undaria pinnatifida macroalgae (diet B) and the other where abalone were fed 25% M. pyrifera, 25% U. pinnatifida, and 50% Adam & Amos Abalone Food, where the latter is an industry standard diet (diet C). The organic contents of the diets were much higher than natural sediments and varied such that diet A (76.40%) > diet B (54.50%) > diet C (37.00%). Diet had a significant effect on S. mollis ingestion rates, assimilation efficiencies, and consequently energy budgets and growth rates. Greater quantities of organic matter (OM) from diet A and diet B were ingested and assimilated by the sea cucumbers compared with the OM in diet C. The energy budgets indicated that after taking routine metabolism into account, all sizes of sea cucumbers had energy to allocate to growth when offered diet A and diet B, but only juveniles had energy to allocate to growth when offered diet C. Fecal excretion rates when offered diet A and diet C at 14 C were greater than those at 18 C, but neither was significantly different from that at 16 C. Ammonia excretion rates increased nonlinearly with temperature for small and medium sea cucumbers but not for large sea cucumbers. Weight‐standardized respiration rates increased with temperature and unexpectedly with animal size, which may have been because of the narrow weight range of test animals biasing the results. These results suggest that industry standard type abalone waste lacks sufficient energy to meet the metabolic requirements of mature sea cucumbers but that growing juveniles on these wastes appears to be feasible and warrants further investigation.     

海参在加工过程中的组分与食品结构变化

海参是我国传统的滋补海洋食品与重要的经济水产品。海参极易自溶的食品原料学特性决定了绝大部分海参原料需要经过加工才能进入市场流通与消费,使得加工成为海参产业链的关键环节。明确海参在加工过程中的组分与食品结构变化,是阐释海参产品品质形成机理的核心,对设计开发海参高品质加工新技术具有重要的理论指导意义,是关乎海参产业发展的关键科学问题。本文概述了海参的组分及食品结构特征,归纳了海参的关键加工环节,以此为背景着重梳理了海参在水煮、干燥、复水、酶解、即食海参加工等过程中组分及食品结构变化的相关研究进展,提出了深入研究的建议,以期加速上述科学问题的解答、推动海参产业的高质量发展。