Now showing items 1-20 of 2949

    • Article

      Abdominal segment deformity syndrome (asds) and fused body segment deformity (fbsd) in cultured Penaeus indicus 

      The abdominal segment deformity disease (ASDD) is a new shrimp disease reported only in cultured Penaeus vannamei in Thailand. Shrimp with ASDD have deformed abdominal segment, jagged gut line and bumpy surfaces. Similar signs were observed in cultured P. indicus in the Philippines. However, aside from the signs described for ASDD, some P. indicus showing abdominal segment deformity syndrome (ASDS) had more severe deformities up to the extent that the number of body segments was reduced due to fusion. Shrimp with fused body segment deformity (FBSD) had four instead of five pairs of legs. To account the prevalence of the deformities in P. indicus, shrimp were classified into grossly normal shrimp (NS), shrimp with abdominal segment deformity syndrome (ASDS) and shrimp with fused segments (FBSD). Out of the shrimp sampled, 83.4 ± 5.4% was NS, 10.9 ± 6.2% was ASDS and 5.7 ± 3.0% was FBSD. Morphometric characteristics of the shrimp were measured. There was no significant difference in body weight (BW) among male and female NS, ASDS and FBSD. In both sexes, total length (TL) of FBSD was significantly shorter compared to NS and ASDS. Shrimp samples were also screened to be negative for known infectious viral diseases including white spot syndrome virus (WSSV), infectious hypodermal and haematopoietic necrosis virus (IHHNV), infectious myonecrosis virus (IMNV), P. vannamei nodavirus (PvNV), Macrobrachium rosenbergii nodavirus (MrNV) and Taura syndrome virus (TSV). Occurrence of ASDS and FBSD in post-larvae (PL) produced from captive and wild spawners were also determined. Based on a tank experiment, no significant difference was detected between the percentages of ASDS in PL produced from wild or captive spawners but FBSD was only noted in PL produced from the latter. Deformities generally did not affect the size of P. indicus except for the reduced length of shrimp with FBSD which when coupled with missing pleopods could lead to major economic loss for shrimp farmers if not addressed properly.
    • Conference paper

      Community-based stock enhancement of abalone, Haliotis asinina in Sagay marine reserve: Achievements, limitations and directions 

      ND Salayo, RJG Castel, RT Barrido, DHM Tormon & T Azuma - In K Hajime, T Iwata, Y Theparoonrat, N Manajit & VT Sulit (Eds.), Consolidating the Strategies for Fishery Resources Enhancement in Southeast Asia. Proceedings of the Symposium … Strategy for Fisheries Resources Enhancement in the Southeast Asian Region, Pattaya, Thailand, 27-30 July 2015, 2016 - Training Department, Southeast Asian Fisheries Development Center
      The Sagay Marine Reserve (SMR) under the National Integrated Protected Area System (NIPAS) is one of the many reef areas in the Visayan Sea in the central part of the Philippine archipelago. The SMR covers 32,000 ha or 59% of coastal waters north of the mainland Sagay City. Donkey’s ear abalone is one of the most sought mollusks traded by small-scale fishers in Molocaboc Island located within the SMR. High buying prices in local and international markets compared with other fish catch motivated fishers to target abalone and caused its overfishing. SEAFDEC/AQD, with support from the Government of Japan Trust Fund (JTF), conducted a community-based stock enhancement through a tri-party collaboration between the fisherfolks of Molocaboc Island, the Sagay local government at the village and city levels, and SEAFDEC/AQD. The study showed that the decision and implementation of stock enhancement and the definition of its objectives and relevance involves the strong engagement with stakeholders. For over a period of eight years (2007-2014), we learned that stock enhancement necessarily involve high financial investments and enormous transaction cost over a long period of time which are often not affordable to local governments of coastal communities in Southeast Asia. Thus, community-based collaborations may help achieve enhancement and restocking goals.
    • Conference paper

      Current status of shrimp farming and diseases in Cambodia 

      O Lang & M Sothea - In RV Pakingking Jr., EGT de Jesus-Ayson & BO Acosta (Eds.), Addressing Acute Hepatopancreatic Necrosis Disease (AHPND) and Other Transboundary Diseases for Improved Aquatic … Diseases for Improved Aquatic Animal Health in Southeast Asia, 22-24 February 2016, Makati City, Philippines, 2016 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The farming of penaeid shrimps in Cambodia began in 1989 and has significantly expanded since 1991. Shrimp cultivation has been carried out in the four coastal provinces, i.e. Kampot, Kep, Preah Sihanouk Ville, and Koh Kong. Black tiger shrimp (Penaeus monodon) and whiteleg shrimp (P. vannamei) are the main species being cultured extensively and intensively in brackishwater ponds in Kampot, Kep, and Preah Sihanouk Ville, and Koh Kong, respectively. Extensive shrimp ponds were constructed close to the mangrove areas with some containing mangroves within the pond and stocking density ranging from 5,000 to 20,000 postlarvae/ha. However, the productivity remains low at >100 kg/ ha/ year. On the contrary, intensive culture has a stocking density ranging from 300,000 to 500,000 postlarvae/ha. While high cost of investment for farm establishment, pond construction and farm operation are required, productions of newly established farms have reached 7 to 8 metric tons (MT) /ha per crop.

      The occurrence of white spot disease, monodon baculovirus disease, and yellow head disease was first reported in 1999 among cultured P. monodon in Koh Kong province causing a number of farmers to stop the intensive cultivation of black tiger shrimp. To date, only a small proportion of shrimp farmers have ventured into extensive shrimp farming with approximately 10 ha of shrimp areas currently in operation. To mitigate the negative impacts of shrimp diseases and promote the expansion of the shrimp industry in Cambodia, development of a national reporting system for aquatic animal diseases; capacity building for detection, monitoring and disease surveillance; creation of National Guidelines On Good Shrimp Aquaculture Practices; establishment of subresearch centers and concomitant funding support for marine aquaculture development and extension services; establishment of local shrimp hatcheries and provision of hands-on trainings for farmers; and strengthening collaborations among provincial officers, researchers and farmers network should be accordingly instituted.
    • Conference paper

      Status of acute hepatopancreatic necrosis disease (AHPND) and other emerging diseases of penaeid shrimps in Viet Nam 

      NT Hien, NTL Huong, VD Chuong, NTV Nga, PH Quang, BTV Hang & NV Long - In RV Pakingking Jr., EGT de Jesus-Ayson & BO Acosta (Eds.), Addressing Acute Hepatopancreatic Necrosis Disease (AHPND) and Other Transboundary Diseases for Improved Aquatic … Diseases for Improved Aquatic Animal Health in Southeast Asia, 22-24 February 2016, Makati City, Philippines, 2016 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Acute hepatopancreatic necrosis disease (AHPND), formerly called early mortality syndrome (EMS), was first reported in 2010 among penaeid shrimps cultivated in the Mekong Delta Region of Viet Nam albeit without any laboratory confirmation. The disease subsequently spread to a wide range of shrimp production areas in the same region (Soc Trang: 1,719 ha; Bac Lieu: 346 ha; and Ca Mau: 3,493 ha), so that the Government of Viet Nam requested for technical assistance from the Food and Agriculture Organization (FAO) of the United Nations in 2011. In 2012, FAO supported Viet Nam through the project TCP/VIE/3304 Emergency assistance to control the spread of an unknown disease affecting shrimps in Viet Nam, under which the Department of Animal Health of Viet Nam (DAH) collaborated with the University of Arizona and FAO experts to carry out indepth studies to identify the etiologic agent of the disease. As a result, unique isolates of Vibrio parahaemolyticus was identified as the causative agent of AHPND in 2013. Viet Nam has been vigilant and transparent with regard to aquatic animal diseases through official notifications to the World Organization for Animal Health (OIE) and the Network of Aquaculture Centres in Asia-Pacific (NACA). AHPND outbreaks have no clear temporal pattern with black tiger (Penaeus monodon) and whiteleg (P. vannamei) shrimps showing similar incidence risk. The disease occurs at any stage of shrimp cultivation, i.e. on average about 35 days after stocking. To date, unwarranted outbreaks of AHPND in major shrimp-producing provinces in Viet Nam have been apparently regulated. Aside from AHPND, white spot disease (WSD) has also been a persistent problem responsible for serious economic losses in many shrimp-producing areas in Viet Nam. To prevent and control the further spread of infectious diseases of shrimps including AHPND and WSD, multiple control measures have been implemented including guidance of farmers to improve production conditions, facilities and biosecurity application, active surveillance of shrimp production areas for early warning, screening of broodstock and postlarvae for any OIE listed diseases, regulation on movement of stocks, and collaboration with regional and international organizations in carrying out in-depth epidemiological studies that will be needed in the formulation of pragmatic and holistic disease interventions.
    • Conference paper

      Current status of acute hepatopancreatic necrosis disease (AHPND) and other transboundary diseases of farmed shrimps in Indonesia 

      MS Hastuti & Desrina - In RV Pakingking Jr., EGT de Jesus-Ayson & BO Acosta (Eds.), Addressing Acute Hepatopancreatic Necrosis Disease (AHPND) and Other Transboundary Diseases for Improved Aquatic … Diseases for Improved Aquatic Animal Health in Southeast Asia, 22-24 February 2016, Makati City, Philippines, 2016 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Transboundary diseases have been a constant challenge for the aquaculture industry in Indonesia. In spite of this, Indonesian aquaculture has experienced a steady growth since 2010. Early mortality syndrome (EMS) or acute hepatopancreatic necrosis disease (AHPND) is a serious emerging transboundary disease of cultured shrimp that has not been reported in Indonesia. On the contrary, hepatopancreatic microsporidiosis (HPM) was first detected in 2015. Other previously reported transboundary diseases of shrimp and fish include white spot disease (WSD), Taura syndrome and infectious myonecrosis (IMN), and viral nervous necrosis (VNN) and koi herpesvirus (KHV), respectively. These diseases have been included in the surveillance program conducted in 2016. To avert the spread of these transboundary pathogens in the Indonesian aquaculture facilities and natural waters, competent authorities have been tasked to implement stringent control measures including government policy and regulation, active and passive surveillance, and strengthening farmers and stake holders awareness of the importance of disease control and health maintenance.
    • Article

      Impacts of aquaculture on fish biodiversity in the freshwater lake Laguna de Bay, Philippines 

      MLA Cuvin-Aralar - Lakes and Reservoirs: Research & Management, 2016 - Wiley
      Laguna de Bay is the largest inland water body in the Philippines, being used predominantly for aquaculture and open water fisheries. Aquaculture in the lake began decades ago, with many changes in the lake ecosystem having occurred since that time. Most dominant species for fish culture are introduced species. Other invasive species were also introduced to the lake as escapees from land-based aquaculture facilities. This study was conducted to monitor fish diversity in two adjacent, but distinctly different, sites in the lake, namely an open fishery area (OFS), with no adjacent aquaculture structures, and an aquaculture site (AQS), with cages for the culture of various commodities. Fish traps were installed at both sites, with the traps being sampled at least every 2 weeks from April 2013 to February 2015. The results of pairwise t-tests indicated significantly higher Shannon–Wiener diversity index (H′), evenness (J′), Simpson's similarity index (D) and species richness (s) in OFS than in AQS. In terms of total catch per day, significantly greater fish biomass were obtained from AQS than from OFS. Introduced aquaculture species had a mean dominance of 83% and 47% in AQS and OFS, respectively. However, invasive species introduced from the ornamental fish trade exhibited a mean relative dominance of 10.3% in AQS and 13.5% in OFS. The relative dominance of native species was also significantly higher in OFS (41%) than in AQS (6.5%). The results of this study demonstrated the adverse impacts of aquaculture in regard to the species diversity of fish in localized areas in Laguna de Bay. The dependency of aquaculture on introduced fish species adversely impacted the natural fish population in the lake. Focusing on the culture of commercially important local species for aquaculture, rather than introduced species, will improve fish production of inland waters without accompanying adverse impacts on biodiversity.
    • Conference paper

      Current status of acute hepatopancreatic necrosis disease (AHPND) of farmed shrimp in Malaysia 

      BC Kua, A Iar, A Siti Zahrah, J Irene, J Norazila, NY Nik Haiha, Y Fadzilah, M Mohammed, B Siti Rokhaiya, M Omar & TP Teoh - In RV Pakingking Jr., EGT de Jesus-Ayson & BO Acosta (Eds.), Addressing Acute Hepatopancreatic Necrosis Disease (AHPND) and Other Transboundary Diseases for Improved Aquatic … Diseases for Improved Aquatic Animal Health in Southeast Asia, 22-24 February 2016, Makati City, Philippines, 2016 - Aquaculture Department, Southeast Asian Fisheries Development Center
      A report about a disease problem in cultured whiteleg shrimp (Penaeus vannamei) was first received by the National Fish Health Research Center (NaFisH) in 2011 from Perak State showing signs of white feces and slow death leading to serious mortality rate. Later, in September of the same year, the Malaysian Shrimp Farmers Association (MSFA) reported to Department of Fisheries (DOF) severe mortalities in almost all of the whiteleg shrimp farms throughout Peninsular Malaysia. Sampling of shrimps for disease diagnosis was then conducted by NaFisH. The bacteriological and histopathological examinations revealed respectively the isolation of V. parahemolyticus and massive sloughing of hepatopancreatic epithelial cells. The disease was subsequently identified as acute hepatopancreatic necrosis disease (AHPND). From our 3-year study, the annual prevalence rates of AHPND were 50%, 26% and 73% in 2011, 2012 and 2013, respectively. At present, AHPND still persists in Malaysia but at a lower prevalence. The risk factors associated with the disease were studied, however, varied environmental and management data analyzed were inconclusive to relate any one parameter directly to the disease. To help ensure the early detection of AHPND, an experimental observation study on `gut scorecard was carried out and this was confirmed by PCR and histopathology. Validation of this technique has yet to be carried out to ensure its reliability. We also examined the potential use of some commercial products such as probiotics and disinfectants available in the market but unfortunately results showed that they were not effective in controlling AHPND. Control measures applied by the farmers such as the use of probiotics were also verified but data generated likewise appeared to be inconclusive. On the contrary, our preliminary study on the antibacterial property of the plant extracts, i.e. betel and lemongrass, incorporated in the feed showed some prophylactic and chemotherapeutic potential against AHPND. However, comprehensive in vitro and in vivo trials are still currently being undertaken to elucidate its efficacy and practical applications. To ensure the shrimp industry s sustainability in Malaysia, results of our ongoing and future studies aimed at preventing and controlling unwarranted outbreaks of AHPND and other emerging transboundary diseases of penaeid shrimps will be continually disseminated to shrimp farmers and pertinent stakeholders.
    • Conference paper

      Regional response on AHPND and other emerging shrimp diseases in the Asia-Pacific 

      EM Leaño - In RV Pakingking Jr., EGT de Jesus-Ayson & BO Acosta (Eds.), Addressing Acute Hepatopancreatic Necrosis Disease (AHPND) and Other Transboundary Diseases for Improved Aquatic … Diseases for Improved Aquatic Animal Health in Southeast Asia, 22-24 February 2016, Makati City, Philippines, 2016 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Transboundary aquatic animal diseases are among the major concerns for establishing biosecurity measures and strengthening of aquatic animal health (AAH) management capacity (including emergency preparedness) in the region. In aquaculture, biosecurity and AAH management entails protection of fish or shellfish from infectious agents (viral, bacterial, fungal or parasitic) as well as prevention of disease spread from one area to another. Several transboundary aquatic animal diseases have swept the region over the past 25 years causing massive economic and social losses. These include spread and outbreaks of epizootic ulcerative syndrome (EUS) in freshwater fish, viral nervous necrosis (VNN) in marine fish, viral haemorrhagic septicaemia (VHS) in marine and freshwater fish, and several viral diseases in shrimps (e.g. white spot disease [WSD], infectious haematopoietic necrosis [IHHN]). The spread of these transboundary diseases clearly demonstrates the vulnerability of the aquaculture industry to disease emergence where impacts have been aggravated by the lack of effective preparedness and response when diseases emerge.

      Recently, outbreaks of acute hepatopancreatic necrosis disease (AHPND), popularly known as early mortality syndrome (EMS), among cultured shrimps were reported in China and Viet Nam (2010), Malaysia (2011), Thailand (2012), Mexico (2013) and the Philippines (2014). There have been reports of its spread in South American countries but limited report is available in this regard. This disease caused significant losses in the production of Penaeus monodon and P. vannamei in the affected countries. NACA s regional response to this disease during its initial outbreak in Viet Nam, Thailand and Malaysia signified that improved control on transboundary diseases and emergency preparedness are still needed in the region. In collaboration with international organizations (OIE, FAO), NACA has implemented awareness programs, efficient information dissemination, and emergency regional expert consultation to address this disease problem. OIE and FAO also deployed experts to assess the disease and identify the pathogen involved. All of these efforts, together with subsequent studies on prevention and disease management, have paved the way in preventing further spread of this disease to other shrimp-producing countries so far. However, the risk is still very high that this disease will spread, as transboundary movement of live shrimps within and outside the region is inevitable. In addition, other emerging diseases are now affecting production of major cultured shrimps in the region. These include hepatopancreatic microsporidiosis (HPM) caused by Enterocytozoon hepatopenaei (EHP) with confirmed reports from China, Viet Nam, Thailand, Malaysia and Indonesia (unconfirmed reports from India), and viral covert mortality disease (VCMD) which was reported to be affecting cultured shrimps in China.

      By and large, outbreaks of damaging aquatic animal diseases are likely to continue and the potential consequences are likely to increase with the expansion (intensification) of aquaculture systems and introduction of new species for culture. Consequently, the risks associated with emerging and transboundary diseases are shared - shared water bodies and epidemiological links through trade (especially live movement) - thus, a collaborative approach in dealing with these diseases is therefore warranted and necessary.
    • Article

      Embryonic and larval development of hatchery-reared silver therapon Leiopotherapon plumbeus (Perciformes: Terapontidae) 

      FA Aya, VSN Nillasca, LMB Garcia & Y Takagi - Ichthyological Research, 2016 - Springer Verlag
      The embryonic and larval development of hatchery-reared silver therapon Leiopotherapon plumbeus are described to provide essential information on the early life history of this species. Egg size, larval size at hatching, yolk resorption rate, onset of feeding and development of some morphological characters were examined. Fertilized eggs (430–610 µm in diameter) were spherical, yellowish, demersal and slightly adhesive. First cleavage occurred 6 min post-fertilization and embryos hatched 21–24 h post-fertilization under ambient temperature of 27.5 ± 0.1 °C. Newly hatched larvae [1.79 ± 0.04 mm in total length (TL)] with yolk volume of 0.579 ± 0.126 mm3 had no functional or pigmented eyes, mouth or digestive tract. The eyes became fully pigmented and mouth opened [31 and 36.5 hours post-hatching (hph)] shortly before yolk resorption at 39 hph and when larvae had grown to 2.65 ± 0.14 mm in TL. Some morphological characters such as total length, pre-anal length and eye diameter decreased following yolk resorption, which also coincided with the development of foraging capacities shortly before exogenous feeding was initiated. L. plumbeus larvae initiated exogenous feeding at 54 hph, indicating a short (15 h after yolk resorption) transitional feeding period. Larval growth at the early stages of development (54–72 hph) was rapid and steadily increased from 288 to 720 hph, when larvae, 12.05 ± 4.02 mm in TL, closely resembled the external characteristics of their adult conspecifics.
    • Conference paper

      OIE initiatives on acute hepatopancreatic necrosis disease (AHPND) and other aquatic animal diseases in Asia 

      H Kugita - In RV Pakingking Jr., EGT de Jesus-Ayson & BO Acosta (Eds.), Addressing Acute Hepatopancreatic Necrosis Disease (AHPND) and Other Transboundary Diseases for Improved Aquatic … Diseases for Improved Aquatic Animal Health in Southeast Asia, 22-24 February 2016, Makati City, Philippines, 2016 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The World Organization for Animal Health (OIE) is an intergovernmental organization established in 1924 responsible for improving animal health and welfare worldwide to facilitate safe international trade of animals and animal products while avoiding unnecessary impediments to trade. OIE, as a reference organization of the World Trade Organization (WTO), works to set and update its international standards (OIE Codes and Manuals) regularly through transparent and democratic procedures. The Aquatic Code defines an OIE list of notifiable aquatic animal diseases according to the criteria for listing, which comprise consequences, spread and diagnosis. To be listed, a disease should meet the criteria of each characteristic defined in the Aquatic Code. The acute hepatopancreatic necrosis disease (AHPND) has been officially included in the OIE-listed diseases since May 2015 and officially enforced since 1 January 2016. To fulfill its overall vision which can be summarized by its slogan Protect animals and Preserve our Future, the OIE Regional Representation in Tokyo, Japan and Sub-Regional Representation in Bangkok, Thailand, are working in concert to provide regionally adapted services to OIE Members so that surveillance and control of animal diseases in the region may be strengthened.
    • Book chapter

      Sustainable milkfish production in marine fish cages through strong government support and effective public-private partnerships: a case study from Panabo City Mariculture Park in Davao del Norte, Philippines 

      FG Ayson, AM Ventura & EG de Jesus-Ayson - In W Miao & KK Lal (Eds.), Sustainable intensification of aquaculture in the Asia-Pacific region. Documentation of successful practices, 2016 - FAO Regional Office for Asia and the Pacific
      This case study presents the successful practice of sustainable intensification of milkfish aquaculture in marine fish cages under semi-intensive grow-out conditions in the Panabo City Mariculture Park (PCMP) in Davao del Norte, Philippines. Established in 2006, PCMP became operational through the promulgation of a City Ordinance declaring 1 075 hectares of municipal waters in Panabo City as a Mariculture Development Zone/Park. The operations of PCMP were so successful that in just five years it became the third largest among the 63 operational MPs in the Philippines during 2011, with 86 private investors-locators operating a total of 322 units of cages. At present, a total of 372 units of fish cages are operating in the mariculture park (MP). A combination of factors contributed to the successful operation of PCMP, but the success is usually attributed to the effective partnership between the government (both local and national) and the private sector. The Comprehensive MP City Ordinance that governs the PCMP is strictly implemented and includes, among others, the tenurial rights and access to locators. Regulations on distances between cages are strictly enforced and security measures in the total area are jointly undertaken by the government and the locators. The national government, through the Bureau of Fisheries and Aquatic Resources-National Mariculture Center (BFAR-NMC), provides technical support in all aspects from stocking to harvest during the production cycle. BFAR-NMC staff conduct regular periodic sampling of the stocks and compute feeding rates for the stocks which are implemented by the technicians/caretakers. Likewise, BFAR-NMC staff regularly monitor the water quality of the MP and the health status of the stocks. Since it became operational in 2006, the PCMP did not report a single incident of mass fish kill, which indicates that the technical guidelines of MP operations are strictly followed. Workers are trained and organized into groups by BFAR-NMC such as caretakers, cage framers, netters, harvesters, fish processors, and others, and actively participate in discussions related to MP operations to ensure protocols are properly followed. Harvests of stocks are done by skilled workers trained by BFAR-NMC, all done in the “Bagsakan Center” or fish landing area and are well-coordinated. The support facilities in the fish landing area are provided by both the local and national government and the PCMP Producers Association. The operators provide complete data for their operations to BFAR-NMC for record keeping. The strong partnership between the national government through BFAR-NMC, the local government unit, the investors, as well as the acceptance and support from the community for the PCMP is the hallmark of its success.
    • Conference paper

      Latest research on acute hepatopancreatic necrosis disease (AHPND) of penaeid shrimps 

      I Hirono, S Tinwongger, Y Nochiri & H Kondo - In RV Pakingking Jr., EGT de Jesus-Ayson & BO Acosta (Eds.), Addressing Acute Hepatopancreatic Necrosis Disease (AHPND) and Other Transboundary Diseases for Improved Aquatic … Diseases for Improved Aquatic Animal Health in Southeast Asia, 22-24 February 2016, Makati City, Philippines, 2016 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Acute hepatopancreatic necrosis disease (AHPND) is caused by unique strains of Vibrio parahaemolyticus (VPAHPND) and V. harveyi that have transferrable plasmid carrying the virulent PirAB-like toxin genes. The genomes of VPAHPND strains and V. harveyi from Thailand and Viet Nam, respectively, have been characterized by our group. The genome of VPAHPND strains from Mexico, Viet Nam, and China have also been studied by other groups. We have developed a conventional polymerase chain reaction (PCR) and loop-mediated isothermal amplification (LAMP) methods for the detection of AHPND using a primer set that targets the PirAB-like toxin genes of VPAHPND. We have characterized the toxin genes of VPAHPND strains and also constructed a recombinant plasmid (broad host range) carrying PirAB-like toxin genes. Non-VPAHPND strain N7 which does not carry the plasmid and strain FP11 which is carrying a plasmid not coding for the toxin genes were transformed with the plasmid carrying PirAB-like toxin genes. As a result, the transformed N7 and FP11 strains became virulent and killed whiteleg shrimp (Penaeus vannamei) similar to or at par with the virulence of VPAHPND strain. We then fed the whiteleg shrimp with commercial feed containing the formalin-killed VPAHPND strain. After 2 days of feeding, all of the whiteleg shrimp died. These results clearly indicate that the PirAB-like toxin is the virulence factor of VPAHPND.

      We have been investigating the virulence mechanism of the PirAB-like toxin produced by VPAHPND strains. First, we calculated the copy number of plasmid encoding the PirAB-like toxin genes of several VPAHPND strains. The copy number of the plasmid varied, ranging from 1 to 36 copies. Interestingly, VPAHPND strains carrying low copy number of plasmid were more virulent than VPAHPND strains carrying high copy number of the plasmid. These results imply that the copy number of toxin genes is not an important factor responsible for the degree of virulence of the VPAHPND strains. We are also studying other factors associated with the virulence of PirAB-like toxin. Likewise, we are developing prevention methods against AHPND including the use of formalin-killed cell vaccine, IgY additive in feed, and nano-bubble treatment of rearing water. This paper summarizes the current R&D on the disease.
    • Conference paper

      Acute hepatopancreatic necrosis disease (AHPND) of penaeid shrimps: Global perspective 

      MG Bondad-Reantaso - In RV Pakingking Jr., EGT de Jesus-Ayson & BO Acosta (Eds.), Addressing Acute Hepatopancreatic Necrosis Disease (AHPND) and Other Transboundary Diseases for Improved Aquatic … Diseases for Improved Aquatic Animal Health in Southeast Asia, 22-24 February 2016, Makati City, Philippines, 2016 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The Organization for Economic Cooperation and Development (OECD) and the Food and Agriculture Organization (FAO) of the United Nations Agricultural Outlook 2015-2024 reported that fisheries production worldwide is projected to expand by 19% between the 2012-14 base period and 2024, to reach 191 million metric tons (MT) and the main driver of this increase will be aquaculture, which is expected to reach 96 million MT by 2024, 38% higher than the base period (average 2012-14) level. Among the 7 key uncertainties that affect gains in productivity, the potential of animal disease outbreaks to affect aquaculture production and subsequently domestic and international markets are once again highlighted, although for the first time in this outlook. Another milestone document, the Blue frontiers: managing the environmental costs of aquaculture identified a number of fish health issues, including increased risk of the spread of pathogens and diseases with intensification, through increased movement of aquatic animals, inter-regional trade and introduction of new species and new strains, and through the use of trash fish or live feed; concerns on residues and development of drug resistant pathogens brought about by the abuse on the use antimicrobials and other veterinary drugs; limited availability of vaccines; environmental stressors that compromise the immune system; difficulties faced by developing countries in implementing international standards; and the need for legislation, enforcement and capacity building. The issues identified then and now are almost the same.

      Addressing animal health issues in aquaculture is very challenging because the sector is highly complex (with a wide range of diversity in terms of species, systems, practices and environment, each presenting different risks), its fluid environment, and the transboundary nature where fish is considered as one of the most traded commodity, aquatic animals require more attention in order to monitor their health: they are not visible except in tank holding conditions; they live in a complex and dynamic environment and feed consumption and mortalities are hidden under water.

      This paper looks at the status of a newly emerging disease of cultured shrimp, acute hepatopancreatic necrosis disease (AHPND), which has been recognized as the most important non-viral disease threat to cultured shrimp. In particular, this paper presents the highlights of the International Technical Seminar/Workshop: EMS/AHPND: Government, Scientist and Farmer Responses held from 22-24 June 2015 in Panama City, Panama, which was organized under the auspices of an FAO inter-regional project TCP/INT/3502: Reducing and Managing the Risks of AHPND of Cultured Shrimp, being participated by 11 countries, namely: Colombia, Ecuador, Guatemala, Honduras, Mexico, Panama and Peru from Latin America and the Caribbean (LAC) region and India, Iran, the Philippines and Sri Lanka from the Asian region. The Panama EMS/AHPND June 2015 event aimed to provide a platform to improve the understanding of the disease through the lens of governments, scientists and producers and collectively generate practical management and control measures. More than 100 stakeholders from 21 countries representing the government, academe and producer sectors participated in the event. The highlights contain the latest available information at that time (June 2015) about AHPND including the current state of knowledge about the causative agent, the host and geographical distribution, detection methods, risk factors, management and actions of regional and international organizations.
    • Conference paper

      Status of shrimp health management in Myanmar 

      LPW Saw & MM Than - In RV Pakingking Jr., EGT de Jesus-Ayson & BO Acosta (Eds.), Addressing Acute Hepatopancreatic Necrosis Disease (AHPND) and Other Transboundary Diseases for Improved Aquatic … Diseases for Improved Aquatic Animal Health in Southeast Asia, 22-24 February 2016, Makati City, Philippines, 2016 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Extensive cultivation of the black tiger shrimp (Penaeus monodon) started in the 1970 s in Myanmar using trap and hold method. P. monodon postlarvae (PL) were trapped into the ponds measuring approximately 50 to 100 hectares (ha) during high tide. Because these large ponds have no inputs in terms of pond preparation, eradication of predators, water fertilization, and feeding, production volume during the early years of the shrimp industry in the country provided some lucrative income for the farmers. With this promise, a 3-year project aimed at developing the shrimp culture systems into extensive, extensive plus and semi-intensive was implemented by the Department of Fisheries (DoF), Ministry of Livestock and Fisheries (MLF) in 2010. Unfortunately, in that same year, an outbreak of white spot disease (WSD) caused by white spot syndrome virus (WSSV) occurred in ponds stocked with imported postlarvae and devastated the shrimp industry of the country. Moreover, P. monodon samples from Ayeyarwaddy Division (western part of Myanmar) were also found positive for Taura syndrome virus (TSV) and infectious hypodermal and haematopoietic necrosis virus (IHHNV) by polymerase chain reaction (PCR) method in 2010. In addition, yellow head virus (YHV) was also detected in shrimp samples for export in 2014. Fortunately, acute hepatopancreatic necrosis disease (AHPND) has not yet been detected in cultivated shrimps in Myanmar. Because of disease problems, majority of the shrimp farmers have shifted to extensive or traditional shrimp farming. The Aquatic Animal Health and Disease Control Section (AAHDCS) of the DoF formulates the action plans for aquatic animal health and disease control. Thus to keep abreast with the novel techniques used for the detection and management of previously reported and newly emerging diseases of penaeid shrimps, upgrading of laboratory equipment and facilities, and improving the capacity of the departmental personnel on aquatic animal health management are currently being undertaken.
    • Conference paper

      Fishery resource enhancement: An overview of the current situation and issues in the southeast Asian region 

      MJH Lebata-Ramos & EF Doyola-Solis - In K Hajime, T Iwata, Y Theparoonrat, N Manajit & VT Sulit (Eds.), Consolidating the Strategies for Fishery Resources Enhancement in Southeast Asia. Proceedings of the Symposium … Strategy for Fisheries Resources Enhancement in the Southeast Asian Region, Pattaya, Thailand, 27-30 July 2015, 2016 - Training Department, Southeast Asian Fisheries Development Center
      The total global production from capture fisheries has plateaued since the mid 90s. This stagnation in production or reduced productivity of the world’s coastal and marine wild fisheries is caused by overfishing and degradation of habitats through coastal development and destructive fishing methods. Reports have shown that if the current fishing trends continue, all of the commercial fisheries will have collapsed by 2050. To boost production, scientists, fisheries managers, government agencies, and NGOs have been looking at ways of enhancing fish stocks. Replenishing depleted stocks may be done by regulating fishing effort, restoring degraded nursery and spawning habitats or through resource enhancement. Resource enhancement using individuals reared in aquaculture facilities or seed stocks abundant in the wild is becoming a popular method of supplementing depleted stocks. It is one of the many strategies that could help address the decreasing fisheries production in the wild. A brief history of resource enhancement, the aquatic species released in the different countries in the region, the reasons for releasing stocks, and the issues involved, are discussed briefly in this paper. Among the main reasons for resource enhancement are to increase production or enhance stocks and increase food supply and/or family income. Other reasons include protection of endemic and maintenance of endangered species, rehabilitation of degraded natural habitats and for recreation fisheries, among others. Age or size of seeds, seed quality, genetics, governance, economics, biodiversity conservation, politics, and the introduction of exotics are among the resource enhancement issues identified in the region.
    • Conference paper

      SEAFDEC/AQD stock enhancement initiatives: Release strategies established 

      MJH Lebata-Ramos, EF Doyola-Solis, R Sibonga, JB Abroguena, A Santillan & M Dimzon - In K Hajime, T Iwata, Y Theparoonrat, N Manajit & VT Sulit (Eds.), Consolidating the Strategies for Fishery Resources Enhancement in Southeast Asia. Proceedings of the Symposium … Strategy for Fisheries Resources Enhancement in the Southeast Asian Region, Pattaya, Thailand, 27-30 July 2015, 2016 - Training Department, Southeast Asian Fisheries Development Center
      SEAFDEC/AQD’s Stock Enhancement Program started in 2001 with the first stock enhancement initiative on 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 with seahorses Hippocampus spp., giant clam Tridacna gigas, abalone Haliotis asinina, and sea cucumbers Holothuria spp. as priority species. This paper discusses the release strategies that have been established for giant clam, abalone and mud crab.
    • Conference paper

      Status of aquatic animal health activities in Lao PDR 

      V Dalasaen & BV Amnath - In RV Pakingking Jr., EGT de Jesus-Ayson & BO Acosta (Eds.), Addressing Acute Hepatopancreatic Necrosis Disease (AHPND) and Other Transboundary Diseases for Improved Aquatic … Diseases for Improved Aquatic Animal Health in Southeast Asia, 22-24 February 2016, Makati City, Philippines, 2016 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Lao PDR s National Strategy for Fisheries stipulates the expected outcomes, work plan, and framework aimed at attaining the implementation of current plans and long-term projects up to 2020. Government estimates percent per capita consumption of aquatic animals and aquatic animal products at 15 kg per annum, i.e. accounting for about 40% of the animal protein intake, and targets to increase its per capita availability of fish to 23 kg by the year 2020.

      Lao PDR does not have areas for shrimp culture but researches on the migration pattern and reproductive biology of indigenous shrimp species found in the rivers have been undertaken. Inspection of documents for import, transit and export of live aquatic animals at international checkpoints before entry into Lao PDR has been likewise implemented. With regard to importation, permission of import-export (final destination and origin country), certificate of pedigree, and certificate of sanitary quality are being required. In addition, disease-free status (especially those notifiable to the World Organization of Animal Health [OIE]) of imported shrimps and other aquatic organisms is mandatory at international checkpoints before entry into Lao PDR. For shipments suspected to harbor diseases, samples are sent for analysis at the Namxouang Aquaculture Development Center (NADC), Department of Livestock and Fisheries, Ministry of Agriculture and Forestry, Vientiane, Lao PDR.
    • Article

      Colour preference and colour vision of the larvae of the giant freshwater prawn Macrobrachium rosenbergii 

      G Kawamura, T Bagarinao, ASK Yong, IMX Jeganathan & LS Lim - Journal of Experimental Marine Biology and Ecology, 2016 - Elsevier
      This paper reports on the innate colour preference and colour vision in the hatchery-reared larvae (10–16 days old, stages IV–VIII) of the giant freshwater prawn Macrobrachium rosenbergii (De Man) based on their response to coloured beads in a grey-walled tank under natural illumination. Plastic beads (4.1 mm in diameter) of different colours (dark blue, light blue, light green, yellow, red, white, black, and grey) in various combinations were suspended in the water 5 cm from the water surface and 12–20 cm from the tank walls where the larvae rested in the absence of aeration. The larvae swam head first straight toward the beads and gathered around them. The number of larvae was highest around the dark blue, light blue, and white beads; lowest around the black, red, and light green beads; and moderate around the yellow bead. Tests with different colours in combination with three shades of grey indicated that the larvae of M. rosenbergii discriminated colours by chromaticity. The preference for blue seemed to be an innate rather than a learned ability since the larvae did not prefer the yellow and red beads that were more similar to the colours of the egg custard and the Artemia nauplii on which they had been reared.
    • Article | Short report

      Early appearance of the retinal tapetum, cones, and rods in the larvae of the African catfish Clarias gariepinus 

      G Kawamura, T Bagarinao, J Justin & CY Chen - Ichthyological Research, 2016 - Springer Verlag
      In the retina of the African catfish Clarias gariepinus, the pigment epithelium and the tapetum were formed in newly hatched larvae, the cones developed within 2 days, and the rods within 3 days after hatching. The retinal tapetum shone under surface light under a light microscope; the shine was located in the apical projections of the pigment epithelial cells. Early appearance of the retinal elements enables African catfish larvae to see and feed well even in dim light.