Organized by SEAFDEC Aquaculture Department with funding from the Government of Japan, the 3-day International Workshop on Resource Enhancement and Sustainable Aquaculture Practices in Southeast Asia aims to promote and augment regional initiatives on resource enhancement and sustainable aquaculture practices, and to contribute to poverty alleviation, livelihood and food security.

Recent Submissions

  • Book | Conference publication

    Resource enhancement and sustainable aquaculture practices in Southeast Asia: challenges in responsible production of aquatic species : proceedings of the international workshop on resource enhancement and sustainable aquaculture practices in Southeast Asia 2014 (RESA) 

    MRR Romana-Eguia, FD Parado-Estepa, ND Salayo & MJH Lebata-Ramos (Eds.) - 2015 - Aquaculture Department, Southeast Asian Fisheries Development Center
    The conference was held in order to promote and augment regional initiatives on resource enhancement and sustainable aquaculture practices, and to contribute to poverty alleviation, livelihood and food security in Southeast Asia. The contributions of the selected participants during the conference which are contained in this volume are cited individually.
  • Conference paper

    Current status of sustainable aquaculture in Cambodia 

    O Lang - 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
    In Cambodia, the extension of technologies in fish aquaculture is a vital activity that contributes to improving the daily livelihood of the rural poor farmer communities. Technology extension was introduced since 1994 through a project of the Asian Institute of Technology (AIT) and other local non-government organizations (NGOs) or international organizations (IOs) in some fish production deficient provinces. Prior to the introduction of such activities, wild fish were still abundant. From then to date, aquaculture extension is being done under the Freshwater Aquaculture Improvement and Extension Project Phase II of Japan International Cooperation Agency (FAIEXII-JICA), and Department for International Development/Danish International Development Agency (DFID/DANIDA) Projects.

    Recently, aquaculture extension is one of the national policies under the National Rectangular Strategy Policies of the Government. There are several different freshwater aquaculture systems including floating cage/pen culture, earthen pond culture and rice-fish culture, and other fish culture in smallwater bodies or aquaculture-based fisheries in Cambodia as practiced in over 20 provinces and cities, with less development focused on coastal aquaculture.

    Freshwater aquaculture production continued to grow over the past two decades and increased from 1,610 tons in 1984 to 20,760 tons in 2004, representing 11.9 times increase or growth of 16.3% per year This further increased to 74,000 tons in 2012, representing 11.9 times increase or a growth rate of 15% per year. However, aquaculture development in Cambodia is in its infancy stage compared to other countries in the region. It has encountered some problems and constraints during its development, which include inadequate and unreliable supply of good quality seed; lack of capital, fund or credit for aquaculture investment; inadequate knowledge of aquaculture technology; inadequate manpower for aquaculture extension service; and climate change, which have adversely impacted aquaculture development in Cambodia.

    In order to achieve the goal of supplying the nation s future fishery requirements through aquaculture, the Cambodia Fisheries Administration (FiA) published the Strategic Planning Framework (SPF) for Fisheries (2010-2019). Within this framework, the scenarios for future fish demand-supply for 2019 suggest that aquaculture production will increase by 15% per year to 185,000 tons by the end of 2019.
  • Conference paper

    Inland fisheries resource enhancement and conservation practices in Myanmar 

    H Thein - 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
    Myanmar has impressive freshwater capture fisheries. Inland freshwater bodies cover 8.1 million ha of which 1.3 million ha are permanent while the rest are seasonally inundated floodplains. There are repeated references to the crucial importance of fish and fish products in the nutrition of the Myanmar people. Over the past few decades, inland fisheries resources have increased pressure from overfishing, use of destructive fishing gear/methods, pollution and environment changes. In order to make a sustainable inland capture fisheries and conservation of aquatic biodiversity as well as nutritional security and improved rural livelihoods, fisheries resource enhancement and conservation measures have long been adopted in Myanmar since 1967, initiated through a seed replenishment program in natural waters, such rivers, lake, dams, even rice fields, etc. However, the institutional, policy, legislative and financial environments under which enhancement and capture fisheries regimes exist are not conducive to the interests of the fishers. Strong tools for valuation of ecosystem goods and services, enabling governance arrangements and estimation of environmental flows are needed. Fishing communities need to be organized into strong co-management/participatory/community regimes in order to ensure that all stakeholders take part in decision-making process and the benefits accrued are shared equitably by all.
  • Conference paper

    Abalone aquaculture for stock enhancement and community livelihood project in northern Palawan, Philippines 

    BJ Gonzales - 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
    One of the interventions to feed the poorest of the poor fisheries sector in the country is the provision of livelihood in the form of mariculture of high value marine species. In the Philippines, livelihood in rural areas is largely linked to resource depletion, hence it is wise not only to provide livelihood to the community but also to encourage them to conserve and enhance the resources. As part of the revised R&D program, the Western Philippines University partnered with NGO and existing projects to embark on a community-based environment-concerned livelihood project, using hatchery bred abalone, although top shell was also considered for stock enhancement. This is in an on-going project thus, preliminary phases such as abalone production and cage-based grow-out as well as subsequent project plans will be discussed. The objectives of this study were to: (a) share the implementing experiences in this project, (b) identify success and failure drivers of the project, (c) explain the conceptual framework for the MPA-based stock enhancement to be used in this project, and (d) give recommendations to improve the implementation and ensure the success of the project.

    The following activities have thus far been conducted: (a) development of criteria for cage micro-site selection; (b) writing of proposal and provision of financial assistance for hatchery juvenile production through a partnership MOA; (c) presentation of site survey results to beneficiaries and stake holders; (d) conduct of trainings on abalone grow out culture to POs; (e) development and improvement of training module; (f) signing of conservation agreement; (g) giving of cage materials and juveniles to people s organizations; (h) on site coaching; and (i) partial monitoring. The next activities include improvement in juvenile production, conduct of researches on abalone nutrition, and development of market and value chain flow analysis. The conceptual framework for community-managed stock enhancement will follow that of the Department of Environment and Natural Resources-ICRMP, of which the stock enhancement project is anchored on the management of marine protected areas or MPAs.

    The steps in all the activities were documented and while the project was in progress, performance of the participants in training were measured, the training module was improved, the training approaches were revised according to needs, and the growth and survival of juvenile abalone were monitored. The problems identified were low production of juveniles, insufficient food for grow-out, political squabbles, social preparation, and delay in implementation schedule. Recommendations to improve or resolve the problems encountered were also presented in this paper.
  • Conference paper

    Hatchery management techniques for tiger-tail seahorse (Hippocampus comes) 

    SMB Ursua & T Azuma - 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
    Seahorse culture has been practiced throughout the world to meet the demand for global trade and reduce the pressure on wild stocks through overexploitation. Development of culture techniques for seed production of seahorses is one of the most effective measures to avoid such anthropological repercussions on the wild stocks, and is currently being conducted at SEAFDEC/ AQD with the aim to produce seed for stock release to protect these internationally threatened and overexploited species in Southeast Asia. This paper describes the breakthroughs in seahorse breeding and nursery rearing. So far, we have developed water and feeding management schemes that resulted in improved reproductive performance of broodstock and higher survival and growth rates in newborn and juvenile seahorses.

    We highlight the concern of providing desirable food organisms and maintenance of suitable water quality in order to maintain maximum efficiency in the management of the seahorse hatchery. Newborn seahorses fed with formalin-treated food organisms and reared in UV-treated seawater had significantly higher survival and daily growth rate based on stretched height and body weight than those fed with untreated food organisms and reared in both chlorinated and sand-filtered seawater. Broodstocks fed with mysid shrimps showed higher brood size and shorter parturition interval. Thus, improved reproductive performance as well as survival and growth of newborn seahorses were largely influenced by refinement of hatchery management techniques.
  • Conference paper

    Reproductive biology of christian crabs (Charybdis feriatus, Linnaeus, 1758) in San Miguel Bay, Philippines 

    PM Nieves, NR Olfindo & AM Macale - 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
    The reproductive biology of Charybdis feriatus was investigated from April 2012 to March 2013 to determine gonad maturity, gonado-somatic index (GSI), fecundity, breeding cycle and size at first maturity. Every month, samples of 30 specimens were randomly collected. Gravimetric and volumetric methods were used to estimate fecundity. Results showed that Charybdis feriatus breeds continuously with a distinct period of reproductive activity during the northeast monsoon. Spawning peaks in January where higher values of GSI, mature, and berried female crabs were observed. Female gonad (ovary) weights range from 0.5 to 18.1 grams while mean GSI of female and male were 7.35% and 6.27%, respectively. Berried females were present year round, the highest occurring in December (50%). Fecundity ranged from 1,513,660 to 6,357,133 eggs. The smallest reproductively active female was 8.3 cm. Fecundity was highly correlated with size (r2=0.92).

    In view of these observations, the following options are recommended for crab fishery resource management: (1) to set a closed season for crab fisheries, (2) to regulate catches by not taking egg-bearing swimming crabs, and (3) to allow egg-bearing crabs to release its eggs and the larvae in fishing grounds and/or marine protected areas.
  • Conference paper

    Reaching the poor through aquaculture: The case of technology adoption in rural communities at west central Philippines 

    DB Baticados - 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
    Aquaculture is promoted for food security and poverty alleviation in developing countries. This study examines the socio-economic impact of aquaculture technologies extended to calamitystricken rural communities in Nueva Valencia, Guimaras, representing the marine water fishery and in Dumarao, Capiz, representing the inland freshwater fishery at west central Philippines. The adoption pathway employed in both sites was community-based and participatory. The survey was conducted among cooperators and non-cooperators, randomly selected in equal numbers in two sites with 60 respondents each per site using a pre-tested interview schedule.

    Results showed that aquaculture is an acceptable technology both for cooperators and noncooperators. The venture is a profitable business either done individually or collectively through an association, if managed properly. Milkfish cage culture, however, needs big capital that technology adoption among local fisherfolk (Guimaras) is limited. In contrast, tilapia cage culture enables small farmers/fishers in Dumarao to venture on their own. Dumarao growers were able to innovate using local materials like bamboo poles to make their cages afloat instead of drums or plastic containers as buoys. There were, however, environmental, technological and institutional issues deterring technology adoption in both sites. Climate change and institutional issues were the more prevalent concerns of Dumarao growers. The technological issues like fluctuating market price, cost of feeds, and fry supply were more enunciated in Guimaras.
  • Conference paper

    Community-based shrimp stock enhancement for coastal socio-ecological restoration in the Philippines 

    J Altamirano, H Kurokura, ND Salayo, D Baticados, JG Suyo & S Ishikawa - 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
    The reality of declining quality of coastal areas has been evident for many developing countries, especially in Southeast Asia. In the Philippines, rural coastal zones and estuaries are now being characterized by declining wild fisheries resources and degrading environment. This paper presents, as an example, the typical rural coastal towns of New Washington and Batan in Aklan province, Philippines and showcases how the concept of shrimp stock enhancement can provide incentives to restore the environment and provide sustainable fishing livelihood in the area.

    The New Washington-Batan Estuary in northeast Panay Island, Philippines was a productive fishing ground that has been in a state of degenerating brackishwater fisheries and estuarine environment. Average daily catch composed of various species decreased from 24 kg in 1970s to 0.7 kg at present. Shrimp fisheries, the most important livelihood, declined in quality and quantity. The highly-priced and once very abundant tiger shrimp Penaeus monodon was replaced with smaller-sized and lower-priced species like the Metapenaeus ensis. These can be attributed to the conversion of 76% of mangroves to culture ponds in the past 50 years and more than 400% increase in fishing gears since the 1990s. The need to reduce fishing structures and rehabilitate mangroves is evident. However, these drastic changes directly affect fishers livelihood. This paper explores the prospects of P. monodon stock enhancement as positive reinforcement for the estuary s rehabilitation. Number of gears per fisher may have to be reduced but shrimp catches will be relatively high-priced. Simulations with additional tiger shrimp caught due to stock enhancement show that fishers can increase income by more than 4 times from their current PhP 34 gear-1 day-1. Campaigns on the importance of mangrove especially as shrimp habitat can encourage local communities to reforest the estuary especially in abandoned ponds. With effective management, law enforcement, and sustained support from different sectors, shrimp stock enhancement can be a positive strategy in estuarine rehabilitation and livelihood sustainability in the New Washington-Batan Estuary.
  • Conference paper

    Marker-aided genetic stock management: prospects in Philippine aquatic biodiversity conservation and aquaculture 

    MRR Romana-Eguia, M Ikeda & A Kijima - 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
    With the advent of DNA marker-based technologies and applications, genetic stock assessment incorporating molecular marker information has become an important tool in managing resources both for aquaculture and stock enhancement. Local initiatives toward this end have been undertaken by several research and academic agencies particularly those with access to advanced molecular genetic laboratory facilities both in the Philippines and in collaborating foreign institutions. Funds coming from the Philippine Department of Science and Technology and/or international research grants have supported work on commercially valuable species such as tilapia, shrimp, mud crabs, abalone, milkfish and some high value marine fishes with a view of utilizing and in the process, demonstrating the significance of more scientific microlevel assessment of stocks. Information drawn from marker-aided genetic stock evaluation can contribute to a better understanding of the impact of how proper stock management can be more effectively achieved and how this method can gradually translate to improved yields both from culture and fisheries. This paper covers a review of the status of this technology as applied to ongoing fish conservation and aquaculture production efforts in the Philippines.
  • Conference paper

    Feed formulation for sustainable aquaculture 

    RM Coloso - 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
    As aquaculture production of tropical fish and crustacean species becomes more intensified, practical diets need to be formulated to be cost effective and environment-friendly. Ingredients should be included to satisfy the nutrient requirements of the animal, promote optimal fish growth, and boost the income of small-scale farmers and commercial producers with minimal impacts to the surrounding environment. Feed formulation for sustainable aquaculture should aim at increasing aquaculture system performance and profitability, enhancing the animals disease resistance, increasing attractability, palatability, and digestibility of practical diets, and maintaining environmental quality through sound feeding management and good aquaculture practices. More vigorous research and development efforts need to be supported to generate feed technologies that will ensure a steady and reliable supply of safe and high quality aquaculture products to the public while preserving the environment.
  • Conference paper

    Potential of cowpea (Vigna unguiculata L.) meal as an alternative protein source in diets for giant freshwater prawn (Macrobrachium rosenbergii, de Man 1879) 

    FA Aya, ML Cuvin-Aralar & RM Coloso - 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
    Growth trials were conducted to evaluate cowpea Vigna unguiculata (L.) meal as a potential protein source in diets for giant freshwater prawn, Macrobrachium rosenbergii (de Man 1879), reared in tank and lake-based cages. Five isonitrogenous (approximately 37% crude protein) and isocaloric diets were formulated where fish meal (FM) protein was replaced with 0%, 15%, 30%, 45% and 60% cowpea meal protein (or CP0, CP15, CP30, CP45, and CP60, respectively). Results of an 8-week tank trial showed that the final body weight (FBW), percent weight gain, specific growth rate (SGR) and survival of prawns were not significantly influenced by dietary treatments (P > 0.05), although the highest values, except for survival, were observed with CP45. In a lakebased cage trial that lasted for 16 weeks, prawns fed CP30 and CP45 had significantly higher FBW (13.1 and 14.4 g, respectively) compared to other treatment groups (P < 0.05). SGR (4.52 5.00%/ day), survival rates (53-77%), yield (98.5-116.5 g m-2) and feed conversion ratio (FCR; 2.0-2.7) were not affected by increasing levels of cowpea meal in the diets. Based on these results, cowpea meal can be considered as an alternative protein source in diets for M. rosenbergii.
  • Conference paper

    Seed production of the blue swimming crab (Portunus pelagicus) 

    NS Cabacaba & JE Salamida - 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
    The blue swimming crab, Portunus pelagicus, is becoming a commercially important species in the Philippines. The expanding export market for crabs has led to intensified collection and has threatened the wild stocks. This decline has prompted the need for proper management of the remaining resources, and interest in the establishment of hatchery facilities to produce crablets for reseeding and aquaculture.

    This paper presents the production method for P. pelagicus seedstock at the Guiuan Marine Fisheries Development Center. Experiments to improve larval rearing were conducted as well. For seed production, larvae at the zoeal stage were taken from wild-caught berried crabs hatched in 100-L circular drums filled with sand-filtered seawater (32-34 ppt, 28-30°C). Zoeae were stocked at 100 zoea L-1 in rectangular tanks and fed rotifers at 30 ind ml-1 for the first 4 days. Newlyhatched Artemia were given at 1-2 ind ml-1 at zoea 3, and increased to 5 ind ml-1 at zoea 4 to the megalopa stage. Chlorella sp. was maintained in the rearing tanks at 50,000 cells ml-1 as food for rotifers and for water conditioning. Water exchange was done daily at 30-50%, except for the first 5 days of rearing. The development from zoea 1 to megalopa and megalopa to the first crab instar took 10-12 and 4-6 days, respectively. Longer larval development was observed at lower temperature (<26°C). Cannibalism and deteriorating water quality were identified as major causes of mortality. Survival of zoea 1 to megalopa was higher in chlorinated seawater (7.5+2.58%) compared to UV-treated (6.5+1.73%) and sand-filtered (4.0+2.58%) seawater. Trials involving the use of different tank background colors showed that the survival of larvae was highest in black tanks (9.0+1.00%) as compared to those white tanks (1.5+0.58%).

    In nursery rearing, megalopae were stocked at 1-2 ind ml-1 in wide tanks or concrete pond. Strategies to reduce cannibalism were done by providing shelters and sand substrate (>10 cm). As soon as the megalopa molted to crab instars, they were given minced fish, shell meat, Acetes and formulated crab feeds twice daily, ad libitum. After 21 days, crablets were collected manually after partially draining the water in concrete pond. The crablets produced were released in identified fish sanctuaries and marine protected areas region-wide for resource enhancement and for aquaculture research purposes.
  • Conference paper

    Sustainable aquaculture and resources enhancement in Indonesia 

    S Soetardjo & I Adhitya - 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
    With a human population of 230 million and a huge potential for marine and fisheries resources development, Indonesia promotes aquaculture as a major sector to accelerate economic growth for rural communities. There are recent initiatives to improve the country's legal framework to mitigate the adverse impacts of aquaculture and make the aquaculture more sustainable.

    The Directorate General of Aquaculture under the Ministry of Marine Affairs and Fisheries (MMAF) has the mandate to develop the aquaculture sector of Indonesia. Aquaculture has an important role in the development of its national economy and play a key role in rural development. As aquaculture production expands, there is also a growing concern over the impacts on sustainability of aquaculture and resource enhancement as well as food quality and safety requirements of fish products.

    For this reason, there is a need to improve aquaculture technology and its management system in Indonesia to address the need for eco-friendly production process and food safety concerns while maintaining the sustainability of the country's aquaculture sector. The Indonesian Fisheries Act No. 31 (2004) Amendment No. 45 (2009) mentioned that, among others, the Indonesian fisheries management strategies should include the creation job opportunities, improvement of the welfare of fishers and their communities, and ensuring the sustainability of the country's fishery resources and aquatic environment.

    The most critical factors to achieve sustainable aquaculture in Indonesia are the availability of good quality seed, good practice in grow-out systems, healthy aquaculture environment, fish health management, good-quality products, strategic marketing, and improving marketing and stock enhancement. In addition, it is also a concern that the products from aquaculture should meet the quality standard and product safety. This paper presents a review of Indonesian aquaculture in relation to sustainable practices and management schemes to preserve the aquaculture environment, food safety requirements for aquaculture products, food security and to enhance the biodiversity of fishery resources. A policy that was recently established is the development of the marine and fisheries sector based on the principles of the Blue Economy program of the Indonesian government.
  • Conference paper

    Shrimp metabolism: The roles of lactate dehydrogenase (c31), glycogen phosphorylase (c34) and protein kinase (PK) as revealed by RNA interference 

    MVR Tare, H Kondo, I Hirono & MBB Maningas - 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
    Energy metabolism is well-studied in vertebrate systems, providing insights on the genes and mechanisms involved in different pathways necessary for the survival of an organism. Yet, such studies are still lacking in invertebrate systems much more in shrimp. An earlier study has showed several contigs from the black tiger shrimp to be homologous to white spot syndrome virus (WSSV), a devastating pathogen in shrimp, including contig 31-WSSVORF82 (c31) and contig 34-WSSVORF21 (c34). This study aims to unveil the roles of three genes: c31, c34 and protein kinase (PK) in the shrimp system and its possible role in WSSV-infection. Rapid amplification of cDNA ends-polymerase chain reaction or RACE-PCR was used to obtain the full-length sequence of c31 and c34, followed by in vivo gene silencing using RNAi technology, and intramuscularly injecting dsRNA to WSSVchallenged Macrobrachium rosenbergii and Penaeus (Marsupenaeus) japonicus. Gene expression followed for healthy shrimps and dsRNA-treated shrimps.

    Mrc31 was revealed to be the enzyme lactase dehydrogenase (LDH), commonly released during tissue damage and is a marker for disease. The most parsimonious tree pictured Mrc31 to be sister clades to LDH of other shrimp species, Penaeus monodon and P. vannamei, supported with 100% and 72% bootstrap values, respectively. Mrc34 was highly homologous to the glycogen phosphorylase (GP) enzymes of other organisms including that of another shrimp, M. japonicus, bearing a bootstrap value of 99%. For PK, phylogenetic analysis revealed that the three open reading frames (ORFs) from P. monodon, M. rosenbergii and P. japonicus have 30% homology to WSSV-PK supported by a 98% bootstrap value. Mortality data from dsRNA-treated and WSSV-infected shrimps showed that treatment with dsRNA-LDH, GP and PK had significantly higher survival rates compared to that of the controls, Phosphate Buffered Saline (PBS) and Green Fluorescent Protein (GFP). Silencing the three genes in the shrimp has rendered some protective effect against the virus. Gene expression showed that all three genes are present in immune-related organs such as the gills, hepatopancreas and hemocyte. This study is the first to report the possible identities and functions of contigs 31, 34 and PK providing valuable data on the shrimp's genome.
  • Conference paper

    Growth performance of brackishwater enhanced selected tilapia (BEST) reared in brackishwater ponds 

    AV Labastida, CQ Jumawan, AA Abogado, RB Palma & JJ Sabillo - 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
    Tilapia culture contributes greatly to world aquaculture production. Several tilapia strains have been developed locally and one of these has been developed for brackishwater aquaculture. BEST or the Brackishwater Enhanced Selected Tilapia was developed by the Bureau of Fisheries and Aquatic Resources with the aim of promoting brackishwater culture of this commodity to further improve tilapia production in the Philippines. This study will determine the growth performance of BEST reared in organically fertilized brackishwater ponds at three different stocking densities.

    The study was conducted in nine (9) units of 200m2 ponds. Pond preparation was done following standard procedures that include drying, liming, teaseed application and fertilization. Stocking was done after twenty days when primary productivity in the ponds was noted. Three culture systems were used, namely: extensive (Treatment 1 or T1), semiintensive (Treatment 2 or T2) and intensive (Treatment 3 or T3) systems. The study was conducted for 120 days. Results showed that fish in ponds in treatment T1 had an average body weight (ABW) of 52.1g, T2 stocks with ABW of 223.1 g and T3 stocks with an ABW of 214.5 g. Meanwhile, T1 stocks had a survival rate of 91.9% while stocks under T2 and T3 had survival rates of 80 % and 84% respectively. T1 results showed losses amounting to P382 since total revenue of P958 is smaller than total cost of P1,340. T2 harvest on the other hand registered a total revenue of P 10,368 and total cost of P 4,375 hence net return of P 5,634. T3 also had total revenue of P 21,419 with a total cost of over P 8,498 giving a net return of P12, 471. T2 showed a return on investment (ROI) of 128% and a payback period of 0.77 year. T3 had an ROI of 139% and payback period of 0.71 year. Average feed conversion ratio (FCR) in two runs for two treatments are the same at 1.1 Water parameters like DO, salinity, temperature; water level and pH were also taken. Water level in the ponds ranged from 70 to 74 cm, salinity at 6.3-6.9 ppt, DO at 1.5-1.7ppm, temperature at a constant 29°C, monthly pH ranges were from 7.1 to 8.0 and transparency of 34-47 cm.
  • Conference paper

    First record of Laem-Singh virus in black tiger shrimp (Penaeus monodon) in the Philippines 

    CAM Cruz, PC dela Cruz, PCD Alcala, FGM Tagle, ES Santos, MD Santos & MBB Maningas - 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
    Laem-Singh Virus (LSNV), a single-stranded RNA virus that causes growth retardation in Penaeus monodon, is also known as Monodon Slow-Growth Syndrome (MSGS) virus. Black Tiger shrimps afflicted with this virus exhibit unusual dark color, a weight gain of less than 0.1 g in 1 to 2 weeks, unusual yellow markings, bamboo-shaped abdominal markings and brittle antennae. It was first detected in Thailand and the virus quickly spread to neighboring Asian countries such as Malaysia and Singapore. The shrimp economy of countries where infections have occurred experienced losses in the export of live shrimps and broodstocks. An earlier study in 2009 reported that LSNV was not present in the Philippines. However, since no follow-up researches were done in the succeeding years, this study was conducted to detect the presence of virus in selected sites of Luzon. Results based on biased sampling method and RT-PCR data indicated that LSNV is indeed present in the country. This is further supported by DNA sequence data, showing 100% identity with LSNV India isolate. Phylogenetic analysis showed that the Philippine isolate clustered closely with other LSNV isolates. The outcome of this study might have implications in the current practices in the Philippine shrimp aquaculture industry.
  • Conference paper

    A preliminary study on the diagnosis of coral reef healthiness and establishment of coral replenishment technology 

    T Azuma, JJR Tan, J Zarate, J Altamirano, J Gatus & F Sotto - 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
    Field surveys for coral reef through line-intercept-transect (LIT) and temperature profiling using data-loggers were done at three layers of 5, 10, and 15 m depths in coral reef areas, Nogas Island, Anini-y, Antique, Philippines. Preliminary data based on the LIT survey showed that both coverages of substrates by any type of organism and by Scleractinia decreased in the deeper layers. For Scleractinia, Porites sp. occurred predominantly in all the depth layers with the occurrence decreasing with depth. Temperature fluctuation was largest in the 5 m depth layer, where effects of tidal level were also confirmed. While the average temperature decreased with depth, this did not differ beyond 1°C between 5 and 15 m layers during November 2012 to March 2013. Fragments of the Porites sp. and Acropora sp. were sampled and transferred to aquaria at the Tigbauan Main Station of SEAFDEC/AQD. Acropora sp. sampled from the deepest layer alone showed bleaching and thereafter, a part of the fragments regained the color. Experimental trials to clarify the effects of ocean acidification and warming on the health of the coral using the live fragments of Porites sp. showed decreasing trends in both photosynthetic rates and daily growth rates in acidic condition (pH = 7.6), while decrease of zooxanthellae density was observed under warmer conditions (31°C ) for one month. A new methodology for the determination of density of zooxanthellae was established using the fragments of Porites sp. In this study, the need for studies on several coral communities as well as further basic research on coral biology, particularly, responses to the changing environments are discussed for diagnosis of coral reef healthiness and establishment of effective coral replenishment technology.
  • Conference paper

    Utilization of sensors and SMS technology to remotely maintain the level of dissolved oxygen, salinity and temperature of fishponds 

    RC Munoz, RP Calderon, RC Flores, SC Masangcap & JP Angeles - 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
    Due to the occurrence of fish kills in various fish producing areas in our country, millions of pesos and opportunities for the Filipino people had been put into waste. Bataan Peninsula State University (BPSU) collaborated with the Central Luzon Association of Small-scale Aquaculture to devise strategies to address the said problem and prevent further losses.

    More often than not, a fish kill can be attributed to the low level of dissolved oxygen (DO) in the water, decrease or increase in salinity and sudden increase in temperature, which usually occur after heavy rainfall, flooding or high tide, or high levels of ammonia due to decomposing organic matter and high temperature during summer.

    For these reasons, BPSU researchers tested the use of radio frequencies and installed sensors in different areas of the fishpond at various depths to remotely monitor the levels of DO, salinity and temperature of the water. Once these reach critical levels, the installed system which comes with a specific program, will send an alarm through radio frequencies via Short Messaging Services (SMS) technology on the cellular/mobile phone of the caretaker or the fishpond operator. Upon receiving the alarm, caretakers were able to adjust the levels of dissolved oxygen, salinity and temperature of the water by remotely switching on the air compressor or the electric water pump using their cellular/ mobile phone, thus preventing losses due to fish kills.
  • Conference paper

    SEAFDEC/AQD stock enhancement initiatives: release strategies 

    MJH Lebata-Ramos, EF Doyola-Solis, R Sibonga, J Sumbing, JB Abroguena, A Santillan & M Dimzon - 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
    The Aquaculture Department of the Southeast Asian Fisheries Development Center (SEAFDEC/AQD) started its Stock Enhancement Program more than a decade ago with the first stock enhancement initiative on the mud crab Scylla spp. funded by the European Commission. This was followed by another stock enhancement program in 2005 supported by the Government of Japan Trust Fund. In preparation for its implementation, a Regional Technical Consultation on Stock Enhancement of Species Under International Concern was convened in Iloilo City, Philippines in July 2005 to identify species for stock enhancement. During the meeting, seahorses Hippocampus spp., giant clam Tridacna gigas, abalone Haliotis asinina, and sea cucumbers Holothuria spp. were among the priority species for stock enhancement work.

    Stock enhancement, restocking and ranching are management approaches involving the release of wild or hatchery-bred organisms to enhance, conserve or restore fisheries. This paper reports SEAFDEC/AQD release activities and some of the release strategies that have been established for mud crabs, giant clams and abalone.
  • Conference paper

    Larval rearing of silver therapon (Leiopotherapon plumbeus) in outdoor tanks 

    FA Aya, VSN Nillasca, MNC Corpuz & LMB Garcia - 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
    Silver therapon (Leiopotherapon plumbeus, Kner 1864), locally known as ayungin, is an important freshwater food fish species found in Laguna de Bay, the largest lake in the Philippines. Its market price is twice that of other most sought after freshwater fishes such as tilapia and milkfish. However, intense fishing pressure on the species has significantly reduced the wild stock in Laguna de Bay. Studies to develop hatchery techniques for this indigenous freshwater fish species are therefore needed to produce seedstock for possible culture and wild stock rehabilitation.

    This study highlights the successful larval rearing of silver therapon in outdoor concrete tanks. Larvae reared in outdoor tanks with natural food (grown two weeks beforehand) reached the juvenile stage (40 days after hatching (DAH)), suggesting the presence of some suitable live food organisms in pre-conditioned rearing water. However, larval survival rates were low (11.58 ± 6.56% at stocking density of 0.9 larvae l-1), which is probably linked to the density of food items, particularly during the onset of exogenous feeding or due to high stocking density of larvae. To improve the availability of natural food for the larvae, fertilization of the rearing water in the outdoor tanks stocked with larvae at two densities (0.4 and 0.6 larvae l-1) was performed. Larval growth and survival were improved at stocking density of 0.4 larvae l-1 than at 0.6 larvae l-1. Diet composition of first-feeding silver therapon larvae in outdoor tanks inoculated with cultured microalgae (Chorella sorokiniana) and zooplankton was also determined. Larvae were able to consume rotifers and some phytoplankton beginning at 2 DAH and larger preys such as cladocerans and insect larvae starting at 12 DAH.

    The efficacy of raising silver therapon larvae in outdoor tanks using ambient lake water was also evaluated. Larvae reared in ambient lake water grew well but survival (48.44 ± 7.85%) was significantly improved in treatments where tropical almond or talisay Terminalia catappa leaves were added during the first two weeks of larval rearing.

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