海水对虾工厂化循环水养殖系统模式分析

对虾养殖由于受到水资源和虾病的困扰,工厂化循环水养殖已经成为今后对虾养殖的一个重要方向。对虾工厂化循环水养殖系统的结构包括了养虾池、水处理技术、消毒杀菌、增氧技术、水温调节装置等。目前,典型的养殖模式有美国德州跑道式对虾养殖系统、台南室内自动化循环水养虾系统、美国佛罗里达三阶段养殖系统和美国夏威夷基于微藻的循环水对虾养殖系统。文中对这4种典型的对虾工厂化循环水养殖系统的养殖试验情况进行分析比较。     

硇洲岛周围水域虾拖网虾渔获组成

根据2005年渔业资源监测船生产调查资料和现场取样数据,运用数理统计方法分析了虾拖网虾渔获组成、生物学特征以及月份变化等。结果表明:硇洲岛周围水域虾拖网捕获的虾类主要是沿岸性底栖虾类,渔获中优质虾种少,幼虾比例高,墨吉明对虾、日本囊对虾、哈氏仿对虾是虾拖网渔业的主捕虾种,虾渔获组成存在明显的月份变化。为合理利用虾类资源和促进虾渔业可持续发展,应根据虾类特性开发适宜广东沿海虾拖网的选择性捕捞技术,减少幼虾兼捕量。     

熟制与贮藏对凡纳滨对虾挥发性成分的影响

为研究熟制与贮藏对凡纳滨对虾挥发性成分的影响,采用电子鼻及固相微萃取—气相色谱—质谱联用技术分析虾肉的挥发性成分,并采用相对气味活度值和感官评定法评价虾肉风味的变化。结果显示,熟制与贮藏对虾肉中的挥发性成分影响显著。凡纳滨对虾生虾、熟虾、熟虾冷却、熟虾冷却过夜及二次熟制虾分别被检出50、68、63、49和41种挥发性成分。二次熟制后,虾肉中的挥发性成分有所减少,感官上虾的特征鲜香气也略微减弱;一次熟制对虾肉的风味影响不大。生虾肉中检测出的挥发性成分如壬醛和癸醛等对风味有显著性影响;熟虾肉中检测出壬醛、癸醛和十四醛等;二次熟制的虾肉中检测出对风味影响较大的挥发性成分主要是十八醛、二丁基羟基甲苯等。熟虾经过夜(4°C)放置后,其中检测出的挥发性成分种类和总量均减少,但总量差异不显著。研究表明,熟制可显著增加挥发性风味成分种类和总量,二次熟制与一次熟制相比,凡纳滨对虾的关键风味物质种类和含量显著降低;熟虾冷却后4°C贮藏12 h风味差异不显著。     

Reduction of the Phosphate Soaking Time Required for Shrimp Products Using Pulsed Vacuum Condition

Pulsed vacuum (PV) was used to reduce the phosphate soaking time for raw and cooked shrimp, without reducing its quality. The shrimp was soaked in a phosphate solution under cycles of vacuum pressure (15 kPa, 7 min) and atmospheric (ATM) pressure (101 kPa, 3 min). PV-soaked shrimp reached stable absorption faster than ATM-soaked shrimp. At equilibrium absorption, no differences in moisture or phosphate contents were observed between PV- and ATM-soaked shrimp. After cooking, PV-soaked and ATM-soaked shrimp showed no differences in product yield or texture. Therefore, PV soaking reduces soaking time but does not affect the yield of cooked shrimp, increasing production capacity. Moreover, this study suggests that to maximize the yield of raw-soaked shrimp, shrimp should be soaked until the moisture content reaches equilibrium. In contrast, cooked shrimp should be soaked until the phosphate content stabilizes, to produce the highest yield with the lowest soaking time.     

日本沼虾黑鳃病的可溶性蛋白质分析

应用聚丙烯酰胺凝胶电泳的方法，分析了患黑鳃病日本沼虾（Macrobrachium nipponense)肌肉、肝胰腺、心脏和鳃等组织、器官的可溶性蛋白质，结果显示：可溶性蛋白在组织、器官间存在明显差异，患黑鳃病后表现出缺失或增加现象。病虾较健康虾肌肉新增4条谱带，同时减少了3条谱带、肝胰腺新增1条谱带，同时减少了3条谱带；心脏新增3条谱带，同时减少了2条谱带，鳃减少了3条谱带。     

对虾工厂化养殖的系统结构

对虾工厂化养殖是在人工控制条件下,利用有限水体进行对虾高密度养殖的一种生产方式,它依托一定的养殖工程和水处理设施作为技术支撑,融合无公害生产的管理模式,是一种高效的环境友好型养殖。文章就构建对虾工厂化养殖平台中的各系统环节及该种生产模式的概况作系统综述。     

Stimulating effects of pond water on digestive enzyme activity in the Pacific white shrimp, Litopenaeus vannamei (Boone)

Crude enzyme extracts were obtained from the digestive glands of Pacific white shrimp, Litopenaeus vannamei (Boone), reared in oligotrophic well water and eutrophic shrimp pond water to compare digestive enzyme activity between the two groups. Specific activities of serine protease, collagenase, amylase, cellulase, lipase and acid phosphatase were significantly higher (P < 0.01) in pond water‐reared shrimp (PW shrimp) than in well water reared‐shrimp (WW shrimp). For most enzymes assayed, specific activity was more than two times higher in PW shrimp, and cellulase activity was over six times higher. In contrast, chitinase activity was significantly higher (P < 0.001) in WW shrimp. Higher specific activity of most digestive enzymes in PW shrimp was probably due to natural productivity in the pond water that served as a source of organic substrates, and this increased activity may contribute to the growth‐enhancing effect of shrimp pond water.     

Apoptosis does not play an important role in the resistance of 'immune' Penaeus japonicus against white spot syndrome virus

We previously demonstrated that kuruma shrimp, Penaeus japonicus, exposed to white spot syndrome virus (WSSV) became resistant ('immune' shrimp) to subsequent challenge with the virus. The present study investigated the role of apoptosis in the 'immune' shrimp during a secondary challenge with WSSV. When naive kuruma shrimp were intramuscularly injected with WSSV at a high or low dose, apoptosis was often detected by TUNEL assay in the lymphoid organ (LO), mainly in the early stage of the infection. A significantly higher incidence of apoptosis was observed in the LO of the shrimp injected with the high dose of WSSV (cumulative mortality: 100%) than in the shrimp injected with the low dose (cumulative mortality: 0%). When 'immune' and naive shrimp were injected with an equal dose of WSSV, the incidence of apoptosis was significantly lower in the 'immune' shrimp than in the naive shrimp. This difference is assumed to result from a substantial reduction of the virus by humoral neutralizing factor in the 'immune' shrimp. These results suggest that apoptosis is not a principal protective factor in 'immune' shrimp.     

Decrease of Lipid Oxidation for Dried Shrimp (Acetes chinensis) Preservation Using Alkaline Lipase Hydrolysis Technology

ABSTRACT

In this study, the degreasing technology using alkaline lipase hydrolysis for Chinese dried shrimp (Acetes chinensis) was investigated, with the purpose of decreasing lipid oxidation during dried shrimp preservation. The salt, moisture, and lipid contents of the shrimp were 6.01, 32.51, and 2.95%, respectively. The optimum enzymatic hydrolysis condition for effective decrease of shrimp lipid was obtained: lipase concentration 40 U/mL, pH 10, soaking time 60 min, soaking temperature 30°C, and shrimp/liquid ratio 1:20 (w:v). Under this optimum condition, the residual lipid of the shrimp was reduced to 2.28%, and the degreasing rate reached 49%. During 30-day preservation, the thiobarbituric acid-reactive substances (TBARS) value (0.185 mg/kg of dried shrimp and 0.131 mg/kg of degreased dried shrimp at Day 30) of degreased shrimp was lower than the shrimp without degreasing, indicating alkaline lipase hydrolysis could effectively prevent lipid oxidation and inhibit oxidative rancidity during dried shrimp preservation.     

世界对虾生产及其贸易特征分析

文章利用统计数据分析了近20年来世界对虾生产和贸易的主要特征。结果表明,随着对虾养殖业的迅猛发展,世界对虾生产出现了从捕捞到养殖的巨大变化,对虾贸易规模也呈现稳步增长的态势;对虾贸易具有典型的由发展中国家流向发达国家的特点,2006年从发展中国家向发达国家的对虾净出口额不低于98．7亿美元;出口商品结构以冷冻虾为主,制作保藏虾的比例稳步上升;对虾进口主要集中在欧盟、美国、日本3大市场,而对虾出口以东南亚和美洲国家为主,但出口国间的竞争优势差异较大,中国对虾出口竞争力较其它东南亚主要出口国明显要弱。     

中国对虾产业现状及相关研究综述

中国对虾产业在国际上具有重要地位,但近年来中国对虾出口形势面临从未有过的巨大挑战,因此,了解我国对虾产品、产业的现状,加大我国对虾产品与产业的研究,对我国对虾产业增强竞争能力和可持续发展具有一定意义。     

Comparison of microbial community structures in intensive and extensive shrimp culture ponds and a mangrove area in Thailand

ABSTRACT:   A pelagic bacterial community structure was examined in experimental intensive shrimp culture ponds that have a shrimp–mangrove complex aquaculture system, an extensive shrimp culture pond and a mangrove area in Thailand by denaturant gradient gel electrophoresis analysis of polymerase chain reaction amplified partial 16S rRNA genes. Bacterial community structure in the intensive shrimp culture ponds was distinguishable from that of the mangrove area. In the extensive shrimp culture pond, the bacterial community structure resembled that in the mangrove area, but bacterial abundance was as great as that in the intensive shrimp culture ponds. Among the intensive shrimp culture ponds, the bacterial community structure was different between a closed culture system and a shrimp–mangrove complex culture system. Moreover, the bacterial community structure in mangrove planted ponds was close to those in the intensive shrimp culture ponds when shrimp culture was conducted, but it was close to those in the mangrove areas without shrimp culture. These results suggest that intensive shrimp culture with shrimp feed input affects the bacterial community structures in pond water.     

Formation of Glycated Products and Quality Attributes of Shrimp Patties Affected by Different Cooking Conditions

ABSTRACT

The objective of this study was to firstly investigate the impact of the cooking conditions, including boiled, baked, and microwaved treatments, in the presence of 3% powdered sugar and 1% NaCl on the changes of quality attributes and the formation of glycated products in shrimp patties. The levels of carboxymethyllysine (CML), furosine, and fluorescent intensity in boiled shrimp patties were much lower than that in baked shrimp patties and microwaved shrimp patties. Addition of powdered sugar alone in baked shrimp patties and microwaved shrimp patties increased the level of furosine and fluorescent intensity. Furthermore, sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) analysis showed a notably decreased intensity in the band with MW of 17–22 kDa in boiled shrimp patties and microwaved shrimp patties, and a stronger intensity of band, with MW of 75–100 kDa, in baked shrimp patties. Principal components analysis (PCA) further confirmed that the changes of quality attributes and glycated products in shrimp patties caused by cooking methods were greater than that caused by the addition of powdered sugar or NaCl.     

Effects of Diet and Water Source on the Nursery Production of Pacific White Shrimp Litopenaeus vannamei

Penaeid shrimp reared in eutrophic pond water grow significantly faster than shrimp in clear well water, and this growth enhancement is especially pronounced in postlarval shrimp. The objective of this study was to determine if the nutritional benefits of pond water could supplement a lower protein feed for postlarval Pacific white shrimp Litopenaeus vannamei . Sixteen 230-L tanks were stocked with 10-d postlarvae at a density of 350 shrimp/tank. Four treatments (four replicates/treatment) were tested for 6 wk and consisted of: 1) shrimp grown in well water and fed a commercially available 45%-protein feed (W/45); 2) shrimp grown in pond water and fed the same 45%-protein feed (P/45); 3) shrimp grown in well water and fed a commercially available 52%-protein feed (W/ 52); and 4) shrimp grown in pond water and fed the same 52%-protein feed (P/52). At the end of the experiment. mean weight gain (± SE) for shrimp in pond water (1.85 ± 0.03 g) was significantly greater ( P > 0.0001) than shrimp in well water (0.98 ± 0.10 g). Mean weight gain for shrimp fed the 52%-protein feed (1.56 ± 0.13 g) was significantly greater ( P > 0.0001) than shrimp fed the 45%-protein feed (1.26 ± 0.20 g). In addition, there was a significant interaction effect between water source and feed ( P > 0.0001). Mean weight gain for shrimp in the W/52 treatment (1.23 ± 0.04 g) was 68% greater than shrimp in the W/45 treatment (0.73 ± 0.03 g). However, mean weight gain for shrimp in the P/52 treatment (1.90 ± 0.03 g) was only 5% greater than shrimp in the P/45 treatment (1.80 ± 0.04 g). These results suggest that organically rich pond water provides postlarval shrimp with sufficient nutrients to compensate for nutritional deficiencies associated with a lower protein feed.     

Optimizing multi-stage shrimp production systems

Multi-stage penaeid shrimp grow-out systems have considerable advantage over conventional single-stage grow-out systems. A multi-stage shrimp grow-out system has more than one production stage wherein the shrimp stocking density changes as the shrimp grow in size and are moved from one production stage to the next. The shrimp stocking density (shrimp/m²) is at its highest when the shrimp post larvae enter the first production stage and is reduced each time the shrimp are transferred to subsequent stages. The use of multi-stage instead of single-stage production systems has been considered by numerous authors. This paper presents a methodology by which to select the optimum number of stages for a production system and, using available data, demonstrates that optimum efficiency can be achieved, in most cases, by using a two-stage production system consisting of a prolonged nursery stage followed by a grow-out stage.     

对虾细胞培养的研究现状

对虾的细胞培养，是研究对虾不同学科和领域的重要工具之一，至今，国内外已有不关于对虾细胞培养的研究报道，本文综述了不同作者对不同对虾细胞原代培养的结果，比较了其培养方法和培养条件的异同；描述了研究尝试多种方法对原代细胞的传代培养，其中一些方法对对虾细胞系的建立起到了积极的作用，介绍了利用细胞培养技术在对虾不同领域的应用状况，尤其是对对虾病毒性疾病的研究方面应用较多。     

低盐海水罗氏沼虾养殖技术

就河口低盐海区罗氏沼虾幼虾培育及商品虾养成技术进行了综合阐述，包括池塘条件及准备，虾苗运输与放养，饲料投喂技术，隐蔽物设置，低盐海水水质调节技术，虾病防治及商品虾捕捞等。     

Effect of a size-based selection program on blood metabolites and immune response of Litopenaeus vannamei juveniles fed different dietary carbohydrate levels

Blood metabolites in wild and seventh-generation cultivated shrimp were measured to determine how size-based selection could alter the nutritional and immunological conditions of Litopenaeus vannamei. Wild L. vannamei juveniles and a sample of seventh-generation cultured shrimp were acclimated under identical conditions. During 55 days, shrimp were fed a high (HCHO: 44%) or a low (LCHO: 3%) carbohydrate diet for 55 days. Wild shrimp showed a direct relation between dietary CHO and lactate, protein and hemocyte levels indicating that dietary CHO was used for protein synthesis via transamination pathways. In seventh-generation cultured shrimp these parameters were inversely proportional to dietary CHO level, indicating the capacity to synthesize protein from dietary CHO was repressed in cultured shrimp. Farmed shrimp showed a limited capacity to respond to LCHO diets demonstrating high protein dependence in their metabolism and immune response. These results demonstrate that during size-based breeding programs other metabolic process than CHO catabolism can be selected. The incapacity of shrimp to use dietary CHO could limit protein reduction of diets and limit the efforts of the shrimp industry to be ecologically and environmentally profitable.     

Effects of inter‐country aquaculture technology diffusion rates on international shrimp market shares

Abstract

Technology innovation and diffusion in shrimp aquaculture has resulted in increased quantity and supply of shrimp to satisfy expanding consumer demand. Logistic growth curves are estimated to depict the rate of diffusion of shrimp aquaculture technology throughout the major shrimp producing countries. A time series/cross sectional model is applied to 1985–1991 and 1995–1999 production data to evaluate factors influencing shrimp production growth rates. Calculated market shares for each country indicate that operating costs, lagged shrimp price, number of hectares in production, lagged export quantity of shrimp, and market structure influence the aquaculture technological diffusion rates and shrimp produced, and suggest that countries that incorporate technologies into their production system benefit the most from increased market share.     

Using Experimental Microcosms in Shrimp Research: The Growth-Enhancing Effect of Shrimp Pond Water

After preliminary six week experiments showed that shrimp pond effluent from an intensive culture growout pond had the capacity to nearly double shrimp growth in laboratory tanks, an 18 day experiment was designed to determine if similar results occurred in the presence of high quality feeds. The results presented here corroborate the hypothesis that autochthonous factors in shrimp pond water stimulate shrimp growth. These results revealed that performance of currently available shrimp feeds is greatly improved in the presence of pond effluent, regardless of feed quality. Increased feed performance did not appear to be an artifact of supplemental feed availability in pond effluent. The implications from these experiments are that, even in intensive culture systems (above 40 shrimp per m²), in-situ sources of nutrition play an important role in shrimp growth.