Now showing items 1-9 of 9

    • Conference paper

      Aquaculture development in Japan 

      S Mito - In JV Juario & LV Benitez (Eds.), Seminar on Aquaculture Development in Southeast Asia, 8-12 September 1987, Iloilo City, Philippines, 1988 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Along with the growth of the national economy, aquaculture in Japan has steadily developed in recent years. From 1976 to 1985, production of cultured fish and shellfish increased by 28% from 927 thousand mt to 1184 thousand mt. The contribution of aquaculture to total domestic production constituted 22% in value and 9.7% in weight for 1985. Increase in aquaculture production may be attributed to stronger domestic consumer demand for high grade fish products.

      The principal species for culture include sea bream (Pagrus major), black sea bream (Acanthopagrus schelegi), yellowtail (Seriola guinqueradiata), Japanese flounder (Paralichthys olivaceus), pufferfish (Takifugu rubrives), Kuruma ebi (Penaeus japonicus), abalone (Nordicus discus), blood ark shell (Scapharca broughtonii) and edible seaweeds (Porphyra, Undaria, Laminaria). Rapid strides in improved culture techniques have been attained in seed production, grow-out, harvest and disease control in these various species.

      Present trend show increasing reliance on cultured rather than fishery products to meet market demand. In some species, e.g., coho salmon, rainbow trout, oyster and laver, production depends entirely on culture. In other species, production by aquaculture contribute a significant portion to total production. However, to maintain the balance between supply and demand for certain principal aquaculture products, controlled production is now being practised for certain species. In addition to these trends, technical improvements in aquaculture has led to a decrease in the number of management units and area of facilities devoted to production.

      In the future, greater efforts will be directed to diversify the species cultured to suit consumer preference. Emphasis will also be placed on improving taste and texture of cultured products. New types of feed that will not pollute areas around the culture facilities will be developed. Remarkable achievements in biotechnology will also be applied in aquaculture to improve seed quality.

      Parallel with developments in aquaculture, Japan is exerting greater efforts to propagate fishery resources in coastal waters through stock enhancement activities. This is aimed at establishing a multiple fish and shellfish propagation system in the seas surrounding Japan to maintain or increase production from fishery resources.
    • Conference paper

      Biological hazard possibly produced by aquaculture and its control 

      Y Inui - In LMB Garcia (Ed.), Responsible Aquaculture Development in Southeast Asia. Proceedings of the Seminar-Workshop on Aquaculture Development … Southeast Asia organized by the SEAFDEC Aquaculture Department, 12-14 October 1999, Iloilo City, Philippines, 2001 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Blooms of Neterocapsa circularisquama, a novel dinoflagellate, have been causing mass mortality of both wild and cultured shellfish in embayments at the western part of Japan since 1988. Physiological and epidemiological studies suggest that the alga has been partly dispersed with the movement of shellfish in aquaculture activities.

      A recent outbreak of an epizootic iridovirus in red sea bream (Pagrus major) has caused extensive damage to marine fish culture in Japan. A research group at the National Research Institute of Aquaculture (NRIA), collaborating with prefectural fisheries research laboratories and an R&D company, clarified the etiology and developed a diagnostic method and a commercial vaccine.

      Penaeid acute viremia (PAV), a synonym of white spot syndrome, caused catastrophic loses in kuruma shrimp (Penaeus japonicus) culture in Japan. An epidemiological study of the research group at NRIA and the prefectural fisheries research laboratories strongly suggests that the causative virus was newly introduced to Japan from imported shrimp seeds for aquaculture. The group clarified the etiology and established diagnostic methods. Based on their studies, NRIA proposed a protocol to check the virus during larval culture and before seedlings are shipped.
    • Article

      Effect of colored light regimes on the stress response and RNA/DNA ratio of juvenile red sea bream, Pagrus major 

      G Kawamura, TU Bagarinao, K Anraku & M Okamoto - Borneo Journal of Marine Science and Aquaculture, 2017 - Borneo Marine Research Institute, Universiti Malaysia Sabah
      We hypothesized that fish with red-sensitive retina would be stressed by red light and thus inhibited in somatic growth. Red sea bream (Pagrus major) juveniles (total length =3 cm) with red-sensitive retina were chosen to test this hypothesis. We examined the effect of different color lights (red with λmax 605 nm; green with λmax 540 nm; blue with λmax at 435 nm; and white with full spectrum) on unfed juveniles in laboratory tanks. Stress level was measured by the plasma cortisol and glucose concentrations, and nutritional status by muscle RNA/DNA ratio. Under red light, plasma cortisol and glucose, and muscle RNA/DNA were significantly higher than under green, blue, or white light. Our hypothesis was partly supported by previous findings on the effects of the color environment and spectral sensitivity of reared fishes. However, the levels of cortisol, glucose, and RNA/DNA in this study were low compared to published values. It seems that hatchery-bred juvenile red sea bream have adapted to red-rich surface light and are able to cope with the stress of living in surface floating cages which is so different from their deep-water habitats.
    • Article

      Hydrolyzed tuna meat by-product supplement for juvenile red sea bream, Pagrus major, and its effect on growth, enzyme activity, plasma parameters, and apparent nutrient digestibility 

      RE Mamauag, JA Ragaza, S Koshio, M Ishikawa & S Yokoyama - The Israeli Journal of Aquaculture-Bamidgeh, 2014 - Society of Israeli Aquaculture and Marine Biotechnology (SIAMB)
      A growth experiment was conducted on juvenile red sea bream, Pagrus major to investigate the effect of the inclusion in fish diets, of tuna meat by-product hydrolysate which was processed through enzymatic hydrolysis using a commercially available enzyme, derived from Bacillus subtilis. Six experimental diets were formulated in the experiment. Three diets contained 50, 150 and 250 g/kg of TPM-H (tuna meat by-product hydrolysate), and two diets with the unprocessed TPM (tuna meat by-product) at an inclusion level of 50 and 250 g/kg. A control diet was formulated without any addition of the test ingredients. Treatment diets were fed ad libitum to juvenile fish with an initial average body weight of 0.81 ±0.13 g for 56 days. Results of the feeding trial suggest that the inclusion of TPM-H at 250 g/kg in fish diets improved body weight gain rate (3271.58%), feed intake (24.55 g/fish/56 days) and feed conversion efficiency (1.12) of the fish. Apparent nutrient digestibility of hydrolyzed tuna meat by-product improved compared to the unhydrolyzed ingredient. These results suggest that TPM processed as hydrolysates can be efficiently utilized by fish.
    • Conference paper

      Mass larval rearing technology of marine finfish in Japan 

      K Fukusho - In CL Marte, GF Quinitio & AC Emata (Eds.), Proceedings of the Seminar-Workshop on Breeding and Seed Production of Cultured Finfishes in the Philippines, Tigbauan, Iloilo, Philippines, 4-5 May 1993, 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center
      With economic development and increased demand for high price fish, industrial scale marine finfish culture in Japan was started in 1960-1965 for yellowtail Seriola quinqueradiata. Sustainable supply of wild juvenile and development of floating cage with synthetic fiber net have spurred the culture of nearly 30 species and total production in 1991 is 265 x 103 metric tons (nearly 25% of total aquaculture production). Although salmon ranching had been started in 1888, a national project of ocean ranching was only initiated in 1963 with the present target of 26 species of marine finfish. Ocean ranching aims to increase fisheries resources in coastal sea by stocking hatchery-reared juveniles and preservation of environmental capacity and habitat. Therefore, mass production of marine finfish juveniles is being done for the intensive culture in net cage and for stocking coastal sea in Japan.

      Nearly 200 million juveniles are produced by ocean ranching centers (14 national, 49 prefectural, 21 city and town, 53 fishermen's association). The number of target fish is about 60 species (excluding salmon and trout). The main species produced are red sea bream, Pagrus major, flounder, Paralichthys olivaceus, puffer, Takifugu rubrapes, rockfish, Sebastes shlegeli, and mud dab, Limanda yokohamae. More than one million juveniles of these species are produced at one hatchery or ocean ranching center per one fry production season. About 70% of total production of juveniles consist of red sea bream and flounder. Red sea bream could be used to introduce mass larval rearing technology in Japan since its mass production is well developed. The focus of the present paper is the present status and short history of the development in larval rearing technology for red sea bream.
    • Conference paper

      Overview of seafarming and searanching technology in Japan 

      S Umezawa - In F Lacanilao, RM Coloso & GF Quinitio (Eds.), Seminar-Workshop on Aquaculture Development in Southeast Asia and Prospects for Seafarming and Searanching; 19-23 August 1991; Iloilo City, Philippines., 1994 - Aquaculture Department, Southeast Asian Fisheries Development Center
      In 1989, artificial seed production was attained in 37 species of fishes, 16 species of Crustacea, 25 species of shellfishes, and 9 species of other fishery animals in Japan. Eighty species of fishery animal seed, including natural and artificial production, were released in natural fishery grounds during this year. The total mariculture production was 1.3 million tons. This composed of 18% fish, 35% shellfish, 46% seaweed, and 1% of other fishery animals.In recent years, Japan achieved some success in Seafarming and searanching projects. Among these are searanching of Japanese scallop in northern Japan and acoustic habituation system of red sea bream. Searanching of striped jack using artificial seed is also explained.
    • Article

      Semi-mass culture of the dinoflagellate Gymnodinium splendens as a live food source for the initial feeding of marine finfish larvae 

      EM Rodriguez & K Hirayama - Hydrobiologia, 1997 - Springer Verlag
      A technique was developed for the semi-mass culture of the unarmored dinoflagellate, Gymnodinium splendens under laboratory conditions. A maximum cell density of 4600 to 6800 cells ml−1 was observed within 8 to 11 days of culture. An initial feeding test for 8 days with three important marine finfish larvae showed that red spotted grouper, Epinephelus akaara preferred G. splendens fed 200 cells ml−1 with 44% survival. The Japanese stripe knife jaw, Oplegnathus fasciatus, attained 22% survival fed a combination of G. splendens and rotifers (200 cells ml−1 and 5 ind. ml−1, respectively). Red sea bream, Pagrus major larvae did not respond well to the initial feeding of G. splendens alone. Red sea bream were observed to be solely dependent on rotifers (5 ind. ml−1) as initial food. Gymnodinium splendens may be used as a live food in the initial feeding of red spotted grouper larvae (E. akaara) to reduce mortality and to further enhance growth during the critical first few days of rearing.
    • Conference paper

      Status of development and use of alternative dietary ingredients in aquaculture feed formulations in Japan: Recent progress of fish meal replacement study of marine fish 

      S Koshio - In MR Catacutan, RM Coloso & BO Acosta (Eds.), Development and Use of Alternative Dietary Ingredients or Fish Meal Substitutes in Aquaculture Feed Formulation … Ingredients or Fish Meal Substitutes in Aquaculture Feed Formulation, 9-11 December 2014, Nay Pyi Taw, Myanmar, 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Fish meal (FM) reduction in aquafeeds is one of the most important issues in aquaculture in Japan. The progress in research studies on reducing the amount of FM in aquafeeds has been demonstrated in several marine species in recent years. This report summarizes those on three species which are high-valued and intensively cultured in Japan; namely, the red sea bream, the amber jack and the Kuruma shrimp.
    • Conference paper

      Status of resource enhancement and sustainable aquaculture practices in Japan 

      K Okuzawa, T Takebe, N Hirai & K Ikuta - In MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.), Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia: Challenges in Responsible Production … International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia 2014 (RESA), 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Contrary to the rapid increase in the world aquaculture production, fish production in Japan has been decreasing slightly due to the decreasing trend in seafood consumption of Japanese. Aquaculture production is approximately 20% in terms of yield, and 30% in terms of market value, of the country s total fisheries production. In Japan, about 80 species are targeted for release for sea ranching and resource enhancement purposes. The local governments (prefectures) are the main driving force in resource enhancement programs. Chum salmon, Oncorhynchus keta, and scallop Mizuhopecten yessoensisis are examples of successful resource enhancement in Japan. Japanese flounder, Paralichthys olivaceus, and red seabream, Pagrus major, represent intensely released fish species in Japan, and around 10% of the total catch of those species are estimated as released fish. The low price of products and increasing costs of production, such as costs of fuel and fish meal, are the major pressing issues in coastal fisheries and aquaculture in Japan. For aquaculture, the guarantee of food safety, minimization of environmental impact, and management of natural stock populations are highly necessary in order to achieve the sustainability of the industry. For resource enhancement, budget constraint is the major issue, and possible impact on natural stocks caused by released fish should also be considered. The Government of Japan (GOJ) is implementing some measures to rectify unstable business practices of aquaculture and to improve production techniques in aquaculture. For resource enhancement, the GOJ encourages cooperation among local governments (prefectures) for seed production and release of certain targeted species in order to reduce the cost and improve the efficiency of stock enhancement. In Japan, traditionally, the purpose for release was mainly sea ranching, namely harvesting all released animals. Nowadays, actual resource enhancement, i.e. the integrated release program including resource management and development of suitable nursery for released fish, is encouraged by the government. The evaluation and counter measures for the negative impact of stocked fish on genetic diversity of the wild population are also implemented. Recently, marked progress was achieved in seed production technologies of two important tropical fish species, namely coral trout, Plectropomus leopardus, and humphead wrasse, Cheilinus undulatus. These technologies are expected to contribute to the advancement of the aquaculture industry in the South East Asian region.