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Marine crustacean farming: present status and perspectives
- Annie Laubier, Lucien Laubier
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- Journal:
- Aquatic Living Resources / Volume 6 / Issue 4 / October 1993
- Published online by Cambridge University Press:
- 15 February 2007, pp. 319-329
- Print publication:
- October 1993
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For centuries, several species of prawns and crabs have been raised from wild-caught juveniles in coastal brackish-water fish ponds in various countries of south east Asia. The Indonesian "tambaks" are well known examples of such traditional practices. In western countries, since the turn of the century, advances of marine biology and fast increase of marine fisheries enabled the development of large-scale production and release of larval stages of American and European lobsters in a fruitless attempt to restock natural populations. After the Second World War, the increasing demand for crustaceans in United States and Japan was satisfied by opening new prawn fisheries all over the world. A major breakthrough was achieved with the development of hatchery technologies for the penaeid prawn Penaeus japonicus (Hudinaga, 1942 in Japan) and the caridean prawn Macrobrachium rosenbergii (Ling, 1969 in Malaysia), which occurred during the first decades of the second half of this century. Together with the increasing market demand in developed countries for sea food, this led to a considerable interest of both public agencies and private investors in marine shrimp and prawn culture. In western countries, a large number of pioneering commercial ventures, often based on assumptions not scientifically founded, failed. Nevertheless, the aquaculture production of prawns mainly based on wild-caught juveniles increased in South-East Asia and Central America during the 1980s. This overall positive trend should not hide important failures which occurred at a local scale, such as the Taiwanese crisis of 1988 due principally to environmental degradation, resulting in severe disease problems and a near collapse of the farming activity. Following the early period of hatchery technology development, the major scientific achievements were related to food requirements and formulation of compound diets for larvae, juveniles and adults and to a better knowledge of diseases caused by bacteria and several viruses which have been identified from hatcheries and intensive farming ponds. Additional new technological advances have emerged from recent research in the fields of physiology (endocrinology) and genetics. By far, the major part of the world production of marine crustaceans relies on penaeid prawns and, to a lesser extent, on Macrobrachium species. However, some other species of marine crustaceans have potential for aquaculture.
The economic aspects of marine crustacean aquaculture should be considered together with those of the fishing industry: market prices are rather similar, depending on the quality of the product. The balance between market demand and production is an important constraint which, in turn, establishes the success of prawn farming. Since the early 1980s, crustacean aquaculture has increased tremendously in both Asia and America: the world production for 1991 approximated 700,000 tons, with more than 600,000 tons from penaeid prawn culture.
Tissue uptake of radioactive cholesterol in the prawn Penaeus japonicus Bate during induced ovarian maturation
- Akio Kanazawa, Liêt Chim, Annie Laubier
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- Journal:
- Aquatic Living Resources / Volume 1 / Issue 2 / April 1988
- Published online by Cambridge University Press:
- 15 April 1988, pp. 85-91
- Print publication:
- April 1988
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The in vivo distribution and fate of 14C-cholesterol injected in prepuberal female prawns, Penaeusjaponicus Bate, intact (E+) or deprived of their eyestalks (E−), were investigated. Animals were injected at the beginning of the experiment. Three days later, half of them (24 specimens) supported bilateral eyestalks ablation within a 48 hours period. Four days after the ablation, the ovaries of eyestalkless animals were relatively more developed than those of intact animals as seen by the increase in ovarian weight. The total content 14C-cholesterol and/or its metabolic products (total dpm) in whole animals was not significantly different between the two lots of animals and remained nearly constant throughout the experiment.
Distribution of radioactivity (dpm/mg wet weight of tissue) in carcass, muscle, gut, hepatopancreas, eyes and eyestalks and ovaries from E+ and E− after 192 hours of 14C-cholesterol injection indicate that ovaries presented the highest concentration of label (6 to 40 times higher than other organs) while these differences were not statistically significant between E+ and E−. The study of incorporation of 14C-cholesterol in those organs from E+ and E− independent of their volume, expressed as percentage organ radioactivity/whole animal radioactivity, at different time points, indicate that major accumulation was achieved by the carcass and muscle although radioactivity in the muscle progressively increased in inverse correlation with the decrease observed in the carcass. Hepatopanereas, eyes and eyestalks, gut and ovaries showed small incorporation that was kept constant with time in eyes and guts and significantly decreased in ovaries and hepatopancreas. At 192 hours after 14C-cholesterol injection there was an apparent increase in 14C label retention in ovaries from E− compared to E+ that was not statistically significant.
Results indicate that the ovary is presumably the major site of cholesterol metabolism followed by the hepatopancreas. Muscle seemingly is the major site for storage of large amounts of cholesterol and/or its metabolites while eyes and gut have negligeable retention. Furthermore, in our experimental conditions, the requirement for cholesterol in different tissues does not vary significantly with eyestalk ablation suggesting that the phenomenon could be independent of ovarian maturation and moulting.