大黄鱼生态冰温保活技术的初步研究

为优化大黄鱼(Larimichthys crocea)活体运输的条件,对大黄鱼的生态冰温进行探索。分析鱼水质量比和暂养时间2个因素对大黄鱼保活时间的影响,在此基础上设计3因素3水平的正交试验,以期找到大黄鱼保活的适合条件。研究结果显示:大黄鱼的生态冰温为-2℃～7℃;鱼水质量比及暂养时间对大黄鱼保活时间均有显著影响(P0.05);在温度为5℃～7℃、鱼水质量比为1∶4、暂养时间为48 h的条件下进行保活,保活时间可超过19 h。本研究结果可为大黄鱼活体运输提供参考。     

珍珠龙胆石斑鱼气调保活工艺的研究

为探讨保活条件对珍珠龙胆石斑鱼无水保活时长的影响，分别以O₂、CO₂、N₂ 3种气体的配比、保活温度、保湿材料进行单因素试验筛选最佳条件范围，正交试验优化气调保活条件，并对不同保活阶段的肌肉成分、血液生化指标进行测定。试验结果表明，气体配比为V(O₂)∶V(CO₂)∶V(N₂)=85∶0∶15、保活温度为15℃、保湿材料为海绵时，珍珠龙胆石斑鱼无水保活时间最长，保活12.5 h其存活率为100%。珍珠龙胆石斑鱼的体质量损失率随保活时间的延长逐渐升高，复水12 h后累积体质量损失率达(6.49±0.15)%。背肌水分含量无显著变化(P>0.05),灰分含量略微升高，粗蛋白、粗脂肪含量逐渐降低。血糖含量、皮质醇含量随保活时间的延长呈曲线变化，尿素氮含量，谷草转氨酶、谷丙转氨酶、酸性磷酸酶活性明显升高，甘油三酯含量、碱性磷酸酶活性有所下降。综上所述，气调保活中珍珠龙胆石斑鱼肾脏、肝脏、免疫系统均受到一定程度的损伤，但复水之后均有所恢复，且保活时间长于纯氧环...     

氨氮对罗非鱼保活试验的影响

正保活运输是保持水产品最佳鲜度,满足消费者对水产品高品质追求的最有效方式。近年来,诸多学者对水产品保活的运输方式、保活温度、时间、密度、供氧方式等主要因素进行了研究,而对保活过程中氨氮的来源及对保活效果的影响研究较少。本项目组经过反复多次试验,发现氨氮是罗非鱼保活过程中的重要指标之一,水体中氨氮含量过高,将直接导致保活过程中罗非鱼死亡,然而其来源并非与养殖中氨氮来源一致。本文以罗非鱼为对象,研究保活过程中氨氮对罗非鱼保活     

淡水鱼碳酸休眠法无水保活运输技术

采用碳酸休眠法,考察碳酸、温度及氯化钠对活鱼无水存活时间的影响.以挥发性盐基氮、乳酸含量等指标评判即杀鲫鱼的品质.结果表明,碳酸法能有效延长活鱼的无水保活时间,显著提高存活率.当碳酸含量在700 mg/L,温度10℃,氯化钠含量0.2%时,鲫鱼的无水保活时间达15 h,比对照组多7 h.无水保活至14 h时鲫鱼的挥发性盐基氮TVB-N值为14.30 mg/100g,仍处于Ⅰ级鲜度.     

MS-222对鳊鱼麻醉保活运输效果的研究

为研究MS-222对鳊鱼保活运输的影响,分析比较了在不同质量浓度MS-222(0、20、40、60、80、100 mg/L和120 mg/L)、不同水温(2、7、15、20℃)和不同鱼水质量比(2∶1、1∶1、1∶3、1∶5)下鳊鱼的存活率,从而确定及筛选最佳的保活运输条件,并检测和分析在保活运输试验中水质指标和鱼体生化指标的变化和影响。试验结果显示,当MS-222质量浓度为60 mg/L、水温7℃、鱼水比1∶3时,保活时间最长,鱼体存活率最高;随着保活时间的延长,水体指标中氨氮含量、微生物、pH均呈上升趋势,而溶解氧水平则呈下降趋势;在鱼体指标中,肌肉中糖原、pH下降,乳酸含量上升;在血液指标中乳酸脱氢酶、谷草转氨酶、血糖、尿素和肌酐均显著增加(P0.05),说明随着保活时间的延长,鱼体肝脏和肾脏组织代谢水平受到一定的影响,但其变化幅度均小于对照组。研究结果表明,在鳊鱼保活过程中可适当使用MS-222麻醉剂以延长存活时间和提高存活率。     

高值贝类保活运输车与鲍鱼应用效果分析

针对当前市场对高值贝类保活运输的需求,研制了现代化的高值贝类保活运输车,可实现保活运输过程中对水温、溶氧和水质等关键存活参数的控制需求,保证优良的保活运输效果。高值贝类保活运输车采用冷却海水喷淋的保活方式,海水采用梯度降温模式,该保活运输车具有制冷、循环水喷淋、增氧、杀菌和水质净化等功能。结合保活运输车相关参数,综合评价了其保活环境控制性能,包括喷淋海水的温度、溶氧浓度及海水流率控制等。利用高值贝类保活运输车开展了保活运输鲍鱼的试验,并与传统的保活运输车进行了存活率和经济性能比较。试验结果表明,高值贝类保活运输车相比传统保活运输车,保活运输7 d,鲍鱼的平均存活率为96.57%,提高了0.76%;宁德往返大连运输120 t鲍鱼的年总费用降低了23.07%,具有较好的经济效益。     

丁香酚麻醉斑点叉尾鮰在不同无水保活温度下的生理生化变化

为寻求丁香酚麻醉斑点叉尾鮰(Ictalurus punctatus)无水保活的最佳条件,研究了不同无水保活温度(0℃、2℃、4℃、6℃和8℃)下斑点叉尾鮰保活5 h以及复苏24 h后的存活率及各生理生化指标的变化。结果显示,丁香酚麻醉斑点叉尾鮰无水保活5 h的最佳保活温度在2℃～6℃,复苏24 h后存活率≥80%;保活5 h后,血液中谷丙转氨酶(ALT)和谷草转氨酶(AST)显著高于保活前(P 0. 05),复苏24 h后,2℃保活组ALT和AST分别可恢复至12. 52 U/L和16. 13 U/L;肌酐和尿素氮含量显著升高(P 0. 05),尤其在6℃下;鱼肉总蛋白、粗脂肪、硬度、咀嚼性呈下降趋势(P 0. 05)。研究表明,在2℃下无水保活,对鱼肉的生理生化指标影响较小。     

菲律宾蛤仔（Ruditapes philippinarum）低温保活方法的研究↑（*）

本文在菲律宾蛤仔（Ｒｕｄｉｔａｐｅｓ ｐｈｉｌｉｐｐｉｎａｒｕｍ）生物学研究基础上，对菲律宾蛤仔在 ２７． ０～－１． ７℃范围内不同温度条件下的存活率，失重率及保活过程中的化学变化等进行了系统的分析研究，确定了菲律宾蛤仔的保活工艺和方法。结果表明，（１）菲律宾蛤仔的最肥季节为每年的 ３～ ７月，出肉率（干物计）最高可达 １０％；（２）最低保活温度为－１．７℃；（３）－１．０～－１．７℃可保活１３天，存活率９１％；（４）－１．０～１．７℃保活，保活时间最长，失重率也低，主要化学成分无显著变化。     

菲律宾蛤仔低温保活方法的研究

本文在菲律宾蛤仔生物学研究基础上，对菲律宾蛤仔在２７．０￣－１．７℃范围内不同温度条件下的存活率，失重率及保活过程中的化学变化等进行了系统的分析研究，确定了菲律宾蛤仔的保活工艺和方法。结果表明，（１）菲律宾蛤仔的最肥季节为每年的３￣７月，出肉率（干物计）最高可达１０％；（２）最低保活温度为－１．７℃；（３）－１．０￣－１．７℃可保活１３天，存活率９１％；（４）－１．０￣１．７℃保活，保活时间最长，     

微波-超声协同强化NaCl改性沸石对罗氏沼虾模拟保活中水质氨氮去除的研究

为提高罗氏沼虾(Macrobyachium rosenberqii)保活的存活时间和存活率,通过正交试验确定微波与超声波协同强化NaCl溶液改性沸石工艺的最佳条件,测试水质氨氮质量浓度与pH、沸石投放量与吸附时间对其吸附性能的影响,研究罗氏沼虾保活过程中存活率与水质指标的变化并对改性沸石进行表征分析。结果显示:以粒径为1～2 mm的沸石进行先微波(230 W、10 min)后超声(560 W、28 kHz、50 min)强化氯化钠(NaCl)溶液(摩尔浓度0.8 mol/L)改性,在氨氮质量浓度为20 mg/L、pH为7.0的水体中投放30 g/L的改性沸石,吸附1 h的水质氨氮去除率相比未改性沸石提高20.88%;表征发现,沸石改性后比表面积增大,晶格未造成破坏,Na~+交换率显著提高,沸石硅铝比升高,能较好维持其电荷平衡;应用于罗氏沼虾模拟保活,使其存活率显著提高,其水质指标均得到有效控制。微波-超声波协同强化氯化钠溶液改性沸石可有效去除氨氮,可延长罗氏沼虾保活时间、提高存活率。     

鲻鱼亲鱼活体运输试验

本文比较了运输鲻鱼亲鱼的几种方法。试验结果表明，用活鱼运输车进行循环洒水运输，运输量大，操作简单，运输效果最好，是较为实用的一种方法。     

Trouble on the reef: the imperative for managing vulnerable and valuable fisheries

Reef fishes are significant socially, nutritionally and economically, yet biologically they are vulnerable to both over‐exploitation and degradation of their habitat. Their importance in the tropics for living conditions, human health, food security and economic development is enormous, with millions of people and hundreds of thousands of communities directly dependent, and many more indirectly so. Reef fish fisheries are also critical safety valves in times of economic or social hardship or disturbance, and are more efficient, less wasteful and support far more livelihoods per tonne produced than industrial scale fisheries. Yet, relative to other fisheries globally, those associated with coral reefs are under‐managed, under‐funded, under‐monitored, and as a consequence, poorly understood or little regarded by national governments. Even among non‐governmental organizations, which are increasingly active in tropical marine issues, there is typically little focus on reef‐associated resources, the interest being more on biodiversity per se or protection of coral reef habitat. This essay explores the background and history to this situation, examines fishery trends over the last 30 years, and charts a possible way forward given the current realities of funding, capacity, development patterns and scientific understanding of coral reef ecosystems. The luxury live reef food‐fish trade is used throughout as a case study because it exemplifies many of the problems and challenges of attaining sustainable use of coral reef‐associated resources. The thesis developed is that sustaining reef fish fisheries and conserving biodiversity can be complementary, rather than contradictory, in terms of yield from reef systems. I identify changes in perspectives needed to move forward, suggest that we must be cautious of ‘fashionable’ solutions or apparent ‘quick fixes’, and argue that fundamental decisions must be made concerning the short and long‐term values of coral reef‐associated resources, particularly fish, for food and cash and regarding alternative sources of protein. Not to address the problems will inevitably lead to growing poverty, hardship and social unrest in many areas.     

The U.S. Wholesale Market for Marine Ornamentals

The market for marine ornamentals encompasses all live marine species (fish and invertebrates) destined for the aquarium trade. In 1998, U.S. imports and exports were valued at approximately US $1.5 billion at the border (all dollar values cited in this paper are $US). In Florida, cultured freshwater and collected saltwater species accounted for $70 million and $4 million, respectively, in annual dockside revenue. To help explain Florida's marine landings and provide suggestions for future resource management and market campaigns that reflect the perceptions of the industry, a survey of wholesalers was initiated in 1999. Preliminary results indicate that there are several intermediate wholesale markets. Florida firms are closer to the supply as many also collect. Wholesalers in other states handle more freshwater product, are larger, and tend to import a larger share of their inventory. Consolidation is expected to continue, but niche markets for eco-friendly firms are expected to grow. In Florida, marketing strategies should focus on the observed higher survival rates and increasing supply of the popular invertebrate species. Many wholesalers are concerned about additional regulations that could reduce the number of collectors and thereby increase supply variability, a noted weakness of the Florida industry.     

Profile of the Marine Aquarium Fish Trade in Hong Kong

A market survey and review of government statistics were carried out to establish imports and exports of marine ornamental fishes into and out of Hong Kong, and to examine the local trade in terms of volume, value and species composition. Official government import figures for marine aquarium fishes were available from 1984 to 1991 and from 1997 and 1998. When compared with net imports, export and re-export volumes over the 15-year period were small, indicating that most imports entered the local market, or were exported unrecorded. The market survey of marine aquarium shops in Hong Kong was carried out between August 1996 and January 1997. From this survey, an annual estimate of 957,563 coral reef fish was calculated for the local trade, valued at HK$57,453,780, with a mean retail price of HK$60 per fish. These figures account for an estimated 2–3% of the global value and volume of marine aquarium fish trade, according to 1992 figures and, compared with government figures, indicate that official declarations of imports are underreported by at least 2–3 fold. A total of 342 marine aquarium fish species, from 49 families, were recorded with about 60% belonging to the families Labridae, Chaetodontidae, Pomacanthidae and Pomacentridae. It was estimated that a large proportion of the trade was in juvenile fishes and almost all fish were less than 10cm in standard length. It was common to see fishes in poor condition, species hard to maintain in captivity, or those listed for conservation concern, on sale. There are no regulations for local traders of live marine fishes other than those relating to either protected species or animal welfare. Licensing of traders in marine fishes could be introduced under existing Hong Kong legislation if fishes were to be re-classified as animals. This is strongly recommended as a step towards regulating and managing the trade in Hong Kong.     

底播虾夷扇贝活品供应链各环节中肠道菌群分析

以鲜活底播虾夷扇贝为研究对象，研究扇贝肠道菌群结构与其生长环境的相似性，并跟踪研究组成供应链的采捕、活水运输、中转、净化Ⅰ、净化Ⅱ及市场等6个环节的活品扇贝的肠道菌群结构变化规律。首先，在扇贝捕捞船现场采集扇贝、海水以及海底沉积物，随后继续对活水运输、中转、净化Ⅰ、净化II及市场等环节跟踪采集扇贝肠道样品；利用基于16S rDNA的PCR-变性梯度凝胶电泳指纹图谱技术对扇贝肠道菌群、沉积物及海水进行分析。变性梯度凝胶电泳指纹图谱分析结明，从即捕扇贝肠道、沉积物及海水中分别获得12、18及20个扩增条带，其中，三者具有9条相同的条带；其余包括活水运输、中转、净化Ⅰ、净化Ⅱ及市场等5个环节的条带数依次为14、16、13、9、22。相似性分析表明，即捕扇贝肠道与海水及沉积物之间菌群组成相似性系数（戴斯系数）分别为66．6％和62．5％；由采捕到市场6环节之间虾夷扇贝肠道菌群相似性系数依次为64．0％、73．3％、69．0％、63．6％及32．3％。采捕后至净化池以及净化后至市场均发生菌群条带的增加，表明采捕后流通环境的改变对扇贝肠道菌群结构有影响；净化处理具有有效的减菌效果；现有捕后处置方式即从采捕至净化Ⅱ，活品扇贝处于比较稳定的胁迫状态，而净化后的产品至消费市场环节的胁迫压力明显，即该零售终端环节对活品质量有重要影响。     

海水鱼的保活运输

常见的水产动物保活运输有增氧法、麻醉法和低温法。而冰温无水保活运输具有运载量大、无污染、质量高等优点，是海水鱼保活运输的发展方向。     

Abdominal puncture as a new method to determine sex in tuviras (Gymnotus sp.)

Tuviras (Gymnotus sp.) are a small fish widely used as live bait in sport fishing. Interest in its culture has increased, but there are still several bottlenecks that need to be solved. For example, the process of sexing in tuviras is difficult since they do not present sexual dimorphism. Thus, the aim of this study was to verify if an abdominal puncture could be used as an inexpensive, fast and reliable technique to identify the sex of adult Gymnotus sp. Before performing the abdominal puncture, five individuals were dissected to determine the exact location of the gonads. Based on this information, the abdominal puncture was performed 6 cm away from the tip of the animal's head and 1 cm below the lateral line with an intravenous infusion set connected to a 5 ml syringe. An abdominal puncture was performed on 24 adult animals that were larger than 20 cm in length. Twenty‐two individuals were sexed correctly, and the accuracy degree was 91.66%. The survival rate of the animals 96 hr after the abdominal puncture was 100%. These results indicate that the abdominal puncture is an easy, simple, fast and inexpensive technique that can be performed in a reliable way.     

Replacing rotifers with a microparticle diet from first feeding in yellowfin seabream,Acanthopagrus latus (Houttuyn), larvae

The possibility to replace or reduce rotifer use with a microparticle diet (MPD) from first feeding in yellowfin seabream larvae was investigated. The experiment consisted of five treatments, a rotifer (100%) control treatment (100R), three experimental treatments, which received a fixed ration of MPD supplemented with 75%, 50% and 25% of the amount rotifer fed in the control treatment (treatments 75R‐MPD, 50R‐MPD and 25R‐MPD respectively), and finally a treatment with the fixed MPD ration only (treatment 0R‐MPD). The results indicated that feeding regimes 100R, 75R‐MPD and 50R‐MPD did not differ significantly in the total length, final survival and stress test resistance. The highest dry weight was achieved in treatments 100R and 75R‐MPD at the end of the experiment compared with treatments 50R‐MPD, 25R‐MPD and 0R‐MPD. The 0R‐MPD treatment showed the lowest growth and survival. Yellowfin seabream larvae were able to ingest inert food directly from the moment of first feeding.     

Shrinking baseline: the growth in juvenile fisheries,with the Hong Kong grouper fishery as a case study

Historic and current information on the grouper fishery from Hong Kong and adjacent waters reveals significant changes in species composition and fish sizes over the past 50 years in this important Asian centre for seafood consumption. Once dominant, large groupers are now rare and small species and sizes prevail in the present‐day fishery. Juveniles comprise over 80% of marketed fish by number among the most commonly retailed groupers, and reproductive‐sized fish are absent among larger species. Current fishery practices and the lack of management in Hong Kong and adjacent waters pose a significant threat to large species with limited geographic distribution such as Epinephelus akaara and Epinephelus bruneus, both now listed as threatened by the IUCN. The heavy reliance on juveniles, not only for groupers, but for an increasing diversity of desired fishes within Asia, potentially reduces stock spawning potential. The ‘shrinking baseline’ in terms of a progressive reduction in fish sizes being marketed in the region can seriously undermine fishery sustainability and recoverability of depleted fish stocks. Fishing pressure on groupers and other valuable food fishes within the Asia‐Pacific is intensifying, the declining long‐term trend of grouper landings in Hong Kong and the increasing focus on juveniles for immediate sale or for mariculture ‘grow‐out’ signal a worrying direction for regional fisheries. Moreover, the common appearance of small groupers for sale will influence public perception regarding what are ‘normal‐sized’ fish. Management attention is needed if these fisheries are to remain viable.