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1.
Size economies and optimal scheduling in shrimp production: results from a computer simulation model
This paper describes a computer simulation model developed to analyze the economics of shrimp production under different stocking regimes, harvesting schedules, and farm sizes. The operation examined is ‘closed-market’ where all stages of production occur on-site, and the final product, adult shrimp, are sold in the market. The model was parameterized using existing market data and secondary production data collected from experimental units at the Oceanic Institute in Hawaii. Results indicated that a weekly stocking and harvesting regime is more profitable than either a biweekly or 8-week stocking and harvesting regime. Scale economies indicated that the minimum farm size is twenty-six growout ponds and the optimal farm size is 64 growout ponds. 相似文献
2.
Socio-economic impacts of shrimp culture 总被引：8，自引：0，他引：8
J H Primavera 《Aquaculture Research》1997,28(10):815-827
Farmed shrimp contributed 27% of total world shrimp production in 1995 with a volume of 712 000 tonnes. Undoubtedly, the shrimp culture industry earns valuable foreign exchange for developing countries and generates jobs across the industry from fry gatherers to growers and processors. However, grave socio-economic consequences – including conversion, expropriation and privatization of mangroves and other lands; salinization of water and soil; decline in food security; marginalization of coastal communities, unemployment and urban migration; and social conflicts – have followed in the wake of, shrimp farm development in the Philippines and other tropical countries. The paper focuses on mangrove ecosystems: the valuation and cost-benefit analysis of their goods and services, and the mangrove-offshore fisheries connection. Research gaps in these areas and the need to internalize the ecological and socio-economic costs (‘externalities’) of shrimp farming are highlighted. Other recommendations include mangrove conservation and rehabilitation, enforcement of existing legislation, and introduction of environment-friendly aquaculture within the broader framework of community-based, integrated coastal area management, e.g. the traditional, extensive polyculture ponds in Indonesia. 相似文献
3.
Kobayashi Takeshi Taguchi Chihiro Futami Kunihiko Matsuda Hiroko Terahara Takeshi Imada Chiaki Khin Gyi Khin Moe Nant Kay Thwe Thwe Su Myo 《Fisheries Science》2020,86(3):551-560
Fisheries Science - The microbiological properties of Myanmar traditional fermented products were characterized using four different brands of bottled shrimp sauce products sold frequently at a... 相似文献
4.
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. 相似文献
5.
Simulation of inorganic nitrogen dynamics and shrimp survival in an intensive shrimp culture system 总被引：1，自引：0，他引：1
Nitrogenous wastes are major concerns in shrimp production and as a component of total farm wastes that impact the aquatic environment. This study describes a simulation model of the role of heterotrophic and nitrifying bacteria on nitrogen dynamics in intensive Litopenaeus vannamei (Boone) culture systems using different feeds and feeding strategies. The model represents: (i) use and remineralization by heterotrophic bacteria of nitrogen wastes and ammonia excreted by shrimp; and (ii) nitrification. The model was quantified using published and unpublished information. The model is multivariate, deterministic and uses a compartment model structure based on difference equations. Evaluation of the model consisted of simulating two indoor and one outdoor experiment that examined the effects of different feeds and feeding levels on nitrogen dynamics. In summary, the model is capable of qualitatively following inorganic nitrogen dynamics. Simulations investigating the effect of heterotrophic remineralization on total inorganic nitrogen suggested that this process may contribute up to 97% of the inorganic nitrogen in the system. This indicates that strategies to increase production, such as increases in feed protein levels or feeding rates, should be carefully evaluated before they are implemented. Future studies need to address bacterial community role in these systems and inorganic nitrogen toxicity mechanisms. 相似文献
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7.
对虾免疫机能研究概况 总被引：16，自引：0，他引：16
Shrimp farming is an important source of revenue and employment in many developing countries.However, infectious diseases have adversely affected the profitability of shrimp industry. For this reason, disease prevention is a priority and shrimp immunology has become a crucial research area of this field. In this paper, the current importance and problems of shrimp-culture were described and the research advances in shrimp immunological defence mechanisms were summarized. The immunological tools are powerful and useful to evaluate the health state of the shrimp. The immunologies of shrimp mainly consist of cellular immunity and humoral immunity. In regard to cellular parameters, they are composed of haemocyte count (THC), differential haemocyte count (DHC) and reactive oxygen intermediates (ROIs). The immunity ceils exert their defence functions through phagocytizing, enveloping, etc, and the changes of THC and DHC are related to health state of shrimp. The ROIs generated during post phagocytic event which maybe an important marker to evaluate the immunological capability and phenoloxidase activity have been considered as a potential marker which is relevant to the health of the shrimp too. Concerning humoral parameters, prophenoloxidase (ProPO) and phenoloxidase,antimicrobial peptides and proteins, hemagglutinin and plasma proteins were described. The determining methods of immunity parameters were discussed. The response of shrimp to pathogens such as bacteria, virus, etc. and environmental factors such as DO, pH, etc, were also reviewed. It is well-known that the immune responses induced by immunizing crustacean or shrimp are mainly the non-specific immune responses. The potential of immunological parameters, including the changes of THC and DHC, the production of ROIs, phenoloxidase (PO) activity, antibacterial activity of plasma, and so on, to appraise the healthy state of shrimp were partly discussed. The future directions for the evaluation of the immunological capability of shrimp were proposed. 相似文献
8.
Saowanee Traesupap Yoshiaki Matsuda Hidenori Shima 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3):215-221
Abstract A simultaneous‐equation model of the supply and demand of shrimp in Japan is constructed, and sensitivity analyses are conducted to measure the effects of changing exchange rates and the stock holdings of shrimp. Using monthly statistics from January 1990 to December 1997, the Japanese own‐price elasticity of supply is found to be inelastic and has a less important effect than the beginning stocks factor. The Japanese demand for shrimp is also found to be price‐and income‐inelastic. The beginning of stock holdings is more sensitive to Japanese shrimp demand than the import price and income. The result of seasonality analyses shows that Japanese shrimp demand also depends on cultural factors. 相似文献
9.
A 120-acre shrimp farm located in southeast Texas has failed for three years to produce expected yields of shrimp despite intensive management. Data obtained from these ponds are combined with observations from other culture facilities to support the hypothesis that the degree of mixing of pond water is the primary limitation to oxygenation of the benthic biomass in a shrimp culture pond. The implication of this conclusion is that shrimp ponds are advection limited; therefore, rational design of such facilities will require detailed data concerning the impact of interactions of pond size, depth and geometry with wind speed, and aerator placement, upon pond mixing. 相似文献
10.
Water turbidity was monitored daily during a 63-day growth trial with juvenile Penaeus vannamei in indoor laboratory tanks. The tanks contained a 2.5 cm layer of soil substrate collected from 14 ponds representing five shrimp farms in Texas. A linear regression model relating turbidity to estimated shrimp length accounted for 49–83% of the total variation in turbidity for the 14 soil groups. For averages of daily turbidity and shrimp length over the 14 soil groups, the linear regression model yielded an r2 = 0.92. Turbidity increased with shrimp length (75–135 mm), apparently because the elevated locomotory or feeding activity of the larger shrimp increased the suspension of soil particles. These results suggest the potential of using water turbidity as a tool for estimating shrimp biomass in ponds. 相似文献
11.
基于GEM模型的6个要素分析我国对虾产业省际间竞争力的现状,研究表明:广东和福建对虾产业集群竞争力普遍较高,广西和海南对虾产业集群竞争力提升水平较快,而上海和山东对虾产业集群竞争力普遍呈下降趋势。文章的结论是:应加大种苗繁育技术投入力度、整合对虾产业链、保护有限的海洋和土地资源以及构建新型养殖关系,确保我国省际间对虾产业集群竞争力的不断提升。 相似文献
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世界对虾生产及其贸易特征分析 总被引：8，自引：2，他引：6
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。 相似文献
14.
[目的] 为探究我国不同产地传统海虾酱的风味特征，探讨风味形成机理。[方法] 从感官量化描述分析和营养成分分析入手，应用气相离子迁移谱和顶空-固相微萃取-气相色谱/质谱联用对不同产地传统海虾酱的风味特征进行探究。[结果] 不同产地传统海虾酱的挥发性风味有显著性差异，气相离子迁移谱和气质联用可以高效表征气味差异。[结论] 不同产地虾酱的挥发性成分的种类和含量均有显著差异，2-乙基己醇、3-乙基-2,5-甲基吡嗪、二甲胺、二甲基三硫和3-甲硫基丙醛等化合物是海虾酱的特征挥发性化合物。QDA结果显示粤港澳产虾酱样品的色泽与风味评分较好，蛋白质和游离氨基酸含量高于其他样品，但腥味也较明显。虾酱的粗脂肪含量与QDA评分没有明显关联。当水分含量介于18%-28%（w%）时，虾酱的粘稠度评分最高。粤港澳产虾酱的特征香气化合物为吡嗪类，如2,6二甲基吡嗪、2-乙基-6-甲基吡嗪等。三甲胺及二甲胺是传统海虾酱的特征风味物，含硫化合物是发酵水产调料的特征风味化合物，但也有可能源于配料中的葱、蒜等香辛料。 相似文献
15.
Export performance of major cultured shrimp producers in the Japanese and US markets 总被引：1，自引：0，他引：1
Increase in shrimp farming was stimulated by growth in world market for high-value shrimp products in the 1980s. The major cultured shrimp producers are located in Asia-Pacific and Latin American regions. The revealed comparative advantage (RCA) method is used to provide insights into the export performance of nine selected shrimp producers in the Japan and United States markets, separately. Shrimp is marketed in a wide variety of product forms, and prices vary according to various product attributes including species, size, taste, quality and origin. The results show that vertical product differentiation concerning different varieties of a good in terms of both quality and price plays an important role on the relative export competition of shrimp products among major shrimp-exporting countries. As a result of the geographical advantage, Asia-Pacific producers enjoy comparative advantage in the Japanese imported shrimp market. Joint ventures with the United States provide great benefits to Ecuador and Mexico in exporting fresh shrimp into the United States market. 相似文献
16.
Timothy W. Flegel 《Journal of the World Aquaculture Society》2019,50(2):249-266
Aquaculture is the fastest‐growing animal production sector, and shrimp production already exceeds that of the capture fishery. Viruses and bacteria account for the majority of disease losses for shrimp farmers. Viral pandemics in the mid 1990s and, more recently, a bacterial pandemic from 2009 to 2015 have led to the conclusion that future, sustainable shrimp aquaculture will depend on the development of more efficient, biosecure production facilities that cultivate specific pathogen‐free (SPF) shrimp, genetically improved for growth and disease tolerance or resistance. Major requirements for development, maintenance, and use of SPF stocks in aquaculture are effective pathogen surveillance and disease prevention methods. When protective measures fail and diseases occur in production ponds, there are currently only a few approved and practical therapeutic methods available for use with bacterial pathogens and none so far for viral pathogens. To improve existing methods of prevention and therapy and to develop new ones, research is being carried out on the nature of shrimp–pathogen interactions. Promising results have been obtained at the laboratory level for possible applications involving the use of immunostimulants for “immune priming” or “trained immunity” of RNA interference and of endogenous viral elements. Some of these promising new directions are discussed. 相似文献
17.
Donna Brennan Helena Clayton Tran Thanh BE 《Aquaculture Economics & Management (Blackwell Science)》2013,17(3-4):127-139
Abstract Extensive forms of shrimp aquaculture have become an important source of income for farm households in the brackish water region of the Mekong Delta, Vietnam. The economic and production characteristics of farms are discussed in this paper, based on a 1997 farm survey, with particular emphasis on shrimp farming practices. Two types of shrimp fanning practice were observed, one based on natural recruitment of seedstock with few supplementary inputs, and the other based on relatively high cash investments in Penaeus monodon seedstock and other inputs. Households practising monodon culture made significantly more income, but faced high risk associated with shrimp mortality. An investigation of the factors affecting monodon yields indicated that investment in higher quality inputs had a positive effect on yield and income. However, further research is needed on the extent to which management can reduce risk of shrimp mortality by investing in such premium quality inputs. 相似文献
18.
Marcelo Araneda Juan Hernández Roger Domínguez-May Miguel A. Vela 《Aquaculture Economics & Management (Blackwell Science)》2013,17(4):431-457
ABSTRACTThe control and management of production factors have been of great economic interest for the aquaculture industry. In this study, the optimal harvesting time that maximizes the net benefits of shrimp cultured in freshwater was determined using a bioeconomic model fitted to six stocking density strategies (90, 130, 180, 230, 280 and 330 shrimp m?2). A model was constructed which included the size heterogeneity of the culture and the results obtained were compared with the traditional model which assumes size homogeneity for all individuals. The results from both models indicated that the stocking density of 90 shrimp m?2 was the best management strategy for optimizing net benefits. The economic importance of taking into account size heterogeneity in the culture of the white shrimp in freshwater is discussed. 相似文献
19.
内源酶辅助提取虾壳虾青素的研究 总被引：1，自引：0，他引：1
文章探讨了内源酶对虾青素提取效果的影响,并以高效液相色谱法（HPLC）测定样品中虾青素的质量浓度,研究了pH、温度和酶解时间这3个因素对虾青素提取效果的影响,采用正交试验进行优化,以虾壳虾青素的萃取率作为评价提取效果的指标。结果表明,当酶解最佳工艺条件为pH 4.0,温度50℃,酶解时间1.5 h时,虾青素的萃取率最高,可达32.16μg.g-1湿虾壳,比直接超声提取提高28%。通过空白试验可知,外加脂肪酶对虾青素提取无促进作用,仅利用内源酶即可达到较好的提取效果,且经济节约。 相似文献
20.
Luis Fernando Aranguren Caro Hung N. Mai Linda Nunan Joshua Lin Brenda Noble Arun K. Dhar 《Journal of fish diseases》2020,43(4):403-411
White spot syndrome virus has been a threat to the global shrimp industry since it was discovered in Taiwan in 1992. Thus, shrimp-producing countries have launched regulations to prevent import of WSSV-infected commodity shrimp from endemic areas. Recently, cooked shrimp that is infected with WSSV tested positive by PCR. However, there is no study to determine the infectivity of WSSV in cooked shrimp that tested positive by PCR. In the present study, WSSV-infected shrimp were cooked at boiling temperature for different times including 0, 1, 3, 5, 10 and 30 min. Upon exposure to boiling temperature, WSSV-infected shrimp were fed to SPF shrimp (Litopenaeus vannamei). The result showed experimentally challenged shrimp from 0-min treatment (positive control) indeed got infected with WSSV. However, experimentally challenged shrimp that were fed tissues boiled at 1, 3, 5, 10 and 30 min were not infected with WSSV. Mortality data showed that only the positive control (0-min) treatment displayed high mortality, whereas no mortality was observed in any other treatment category. These findings suggest that cooking shrimp at boiling temperature for at least 1 min might prevent any potential spread of WSSV from endemic countries to other geographical areas where WSSV has not yet been reported. 相似文献