Now showing items 1-20 of 283

    • Conference paper

      Abalone culture: an emerging aquaculture technology 

      AC Fermin - In Fishlink 2001, 29-31 May 2001, Sarabia Manor Hotel, Iloilo City, 2001 - University of the Philippines Aquaculture Society
    • Conference paper

      Ability of sandfish (Holothuria scabra) to utilise organic matter in black tiger shrimp ponds 

      S Watanabe, M Kodama, JM Zarate, MJH Lebata-Ramos & MFJ Nievales - In CA Hair, TD Pickering & DJ Mills (Eds.), Asia-Pacific tropical sea cucumber aquaculture. Proceedings of an international symposium held in Noumea, New Caledonia, 15-17 February 2011, 2012 - Australian Centre for International Agricultural Research
      Series: ACIAR Proceedings; No. 136
      Due to frequent viral disease outbreaks, a large proportion of shrimp aquaculture in South-East Asian countries has switched from black tiger shrimp (Penaeus monodon) to P. vannamei, an exotic species originally imported from Latin America. One of the causes of disease outbreaks is thought to be poor water and sediment conditions in the shrimp ponds, which may aggravate disease symptoms. To obtain basic information for co-culture methods of black tiger shrimp and sandfish (Holothuria scabra) for possible mitigation of shrimp-pond eutrophication and prevention of disease outbreaks, basic laboratory experiments were conducted at the Southeast Asian Fisheries Development Center—Aquaculture Department in Iloilo, the Philippines. A feeding trial of juvenile sandfish showed that they do not grow well with fresh shrimp feed on hard substrate. Another trial indicated that sand substrate enhances the growth of juvenile sandfish fed with shrimp feed. A feeding trial using shrimp tank detritus, shrimp faeces and Navicula ramosissima (a benthic diatom) as food sources showed that sandfish grew fastest with the faeces, followed by detritus and N. ramosissima. Dissolved oxygen consumption and acid-volatile sulfur levels in the shrimp tank detritus were reduced by sandfish feeding. This suggests that sandfish are capable of growing with organic matter in shrimp ponds, and can bioremediate shrimp-pond sediment.
    • Conference paper

      Acceptability of five species of freshwater algae to tilapia (Oreochromis niloticus) fry 

      JB Pantastico, JP Baldia & D Reyes Jr. - In CY Cho, CB Cowey & T Watanabe (Eds.), Finfish Nutrition in Asia : Methodological Approaches to Research and Development, 1985 - International Development Research Centre
      Unialgal cultures of Oscillatoria quadripunctulata, Chroococcus dispersus, Navicula notha, Euglena elongata, and Chlorella ellipsoidea were fed to tilapia fry for 30 days. Mean weights and survival rates of the fry were highest when given Navicula (105.6 mg, 86%) and Chroococcus (89.1 mg, 90%). Oscillatoria, a filamentous cyanophyte, showed limited acceptability to tilapia fry, possibly because of its larger size in comparison with Chroococcus. Fry fed Chlorella and Euglena did not survive at all.

      C14-labeled algae of the above species were fed to tilapia fry of varying ages. Assimilation rates per fry after 24 hours of feeding with a suitable algal species increased with the age of the fry. Moreover, the same trend as in the growth and survival experiments was observed, i.e., the highest assimilation rates were obtained in 40-day old tilapia fry given Navicula and Chroococcus as natural feeds. On the other hand, negligible amounts of the other three algal species tested were assimilated by tilapia fry.

      The above results were explained in terms of the enzyme secretion of tilapias. There seemed to be no transition stage in the feeding habit of both fry and adult tilapia. The acceptability of plant matter in the diet of even the early larval stages was demonstrated.
    • Conference paper

      Acceptability of selected zooplankton and phytoplankton for growing larvae/fry of bighead carp (Aristichthys nobilis). 

      SF Baldia, JB Pantastico & JP Baldia - In The China Society of Fisheries, 1990 - Proceedings of the Asian Symposium on Freshwater Fish Culture, 11-15 October 1985, Beijing, China
    • Conference paper

      Acetes as prime food for Penaeus monodon larvae 

      P Kungvankij, AG Tacon, K Corre, BP Pudadera, G Taleon, E Borlongan & IO Potestas - 1986 - Asian Fisheries Society
      This paper presents research attempts to develop a suitable artificial diet for shrimp larvae with locally-available materials. Larval rearing experiments using finely ground Acetes tissues conducted under various climatic conditions and hatchery systems were completed. In the dry season, larvae in outdoor tanks fed dry Acetes had the highest survival rate (68%) compared to larvae fed Chaetoceros (48%) or fresh Acetes (39%). In contrast, larvae from an indoor hatchery reared with Chaetoceros had higher survival rate (52%) than those fed with Acetes (35%) and fresh Acetes (24%).

      During rainy months, the survival of larvae reared with Skeletonema , dry and fresh Acetes in outdoor tanks was 72%, 52% and 38% and in indoor tanks 62%, 40% and 23%, respectively.
    • Conference paper

      Acute toxicity of formalin to sea bass (Lates calcarifer) fry. 

      FC Pascual, GT Tayo & ER Cruz-Lacierda - In LM Chou, AD Munro, TJ Lam, TW Chen, LKK Cheong, JK Ding, KK Hooi, HW Khoo, VPE Phang, KF Shim & CH Tan (Eds.), The Third Asian Fisheries Forum. Proceedings of the Third Asian Fisheries Forum, 26-30 October 1992, Singapore, 1994 - Asian Fisheries Society
    • Conference paper

      Acute toxicity of mercury to Oreochromis niloticus fingerlings 

      MLA Cuvin-Aralar - BIOTROP Special Publication, 1991 - SEAMEO BIOTROP
      Fingerlings of Oreochromis niloticus were exposed to the following mercury (as HgCl2) concentrations: 0.005, 0.01, 0.02, 0.03, 0.04, 0.05 and 0.06 mg l-1 Hg of water. Hyperactivity and erratic swimming were the first indications of mercury intoxication. Scoliosis, a curvature in the mid-trunk region, was observed in some fish in the 0.03 - 0.06 mg l-1 Hg tanks. The occurrence of scoliosis is significantly correlated with mercury concentration. The 24 hour LC50 (0.0375 mg l-1 Hg) did not differ significantly with the 96 hour LC50 (0.0350 mg l-1 Hg).
    • Conference paper

      Aeromonas hydrophila in the epizootic ulcerative syndrome (EUS) of snakehead, Ophicephalus striatus, and catfish, Clarias batrachus: quantitative estimation in natural infection and experimental induction of dermo-muscular necrotic lesion 

      Snakehead (Ophicephalus striatus) and catfish (Clarias batraclus) with the Epizootic Ulcerative Syndrome (EUS) were sampled for bacteria. Total bacterial counts of skin and muscle/dermal lesions revealed mean colony forming units (CFU) per gram tissue of 1.22 x 103, 1.40 x 105, 5.31 x 195 and 1.14 x 107 in apparently normal, slightly lesioned, moderately lesioned and severely lesioned snakehead samples, respectively. In catfish, mean CFU per gram tissue were 4.30 x 104 and 2.00 x 105 in apparently normal and slightly lesioned specimens, respectively. Kidney samples likewise revealed the presence of bacteria. Bacteria isolated on trypticase soy agar and Rimler-Shotts medium were predominantly Aeromonas hydrophila occurring in 90% of snakeheads and in 33% of catfish specimens. Infection experiments of A. hydrophila injected intramuscularly into healthy snakehead and catfish induced dermo-muscular necrotic lesions. A dose of at least 106 cells of A. hydrophila was required to induce EUS-like lesions in snakehead and catfish at 21-25 degree C in 24-96 h.
    • Conference paper

      Agar from Gracilariopsis heteroclada from Panay Island, Philippines 

      MTR de Castro - In HP Calumpong & EG Meñez (Eds.), Proceedings of the 2nd RP-USA Phycology Symposium/Workshop, Supplement, 6-10 January 1992, Cebu City, Philippines, 11-18 January 1992, Dumaguete City, Philippines, 1994 - Philippine Council for Aquatic and Marine Research and Development
      This paper aims to determine the optimum NaOH pretreatment strength and duration and also the monthly variations in gel strength, agar yield and sulfate content of agar from Gracilariopsis heteroclada (Zhang et Xia) Zhang et Xia.

      Samples collected from Leganes, Iloilo, Philippines were pretreated with NaOH at different strengths (1,3 and 5%) and duration (30 min and 60 min) at 85-90°C. Agar extractions were done by the method of Nelson et al. (1983) Agar yield was calculated based on Santos (1980). Gel strength and sulfate content were determined using the methods of Aguilar-Santos and Doty (1978) and Jackson and McCandless (1978), respectively. Agar gelling and melting temperatures were analyzed in triplicate (Whyte and Englar, 1976). Viscosity in cps, moisture and ash contents in per percent, were determined using standard methods. Analysis of variance and Duncan’s multiple range test were used to compare the gel strength for the NaOH pretreatment experiment and the different monthly samples. Correlation analysis was carried out to determine the relationship between the different parameters analyzed.

      Highest gel strength (641 gm cm-2 ) and lowest sulfate content (7.66 gm/mg SO4) were obtained following alkaline pre-treatment with 5% NaOH for 30 min with agar yield of 32.4 per cent. Gelling and melting temperatures of agar with the highest gel strength were 40°C and 80°C, respectively, while specific viscosity, moisture and ash contents were 7.5 cps, 12.2% and 4.32%, respectively. Agar yield was negatively correlated with NaOH pre-treatment (P<0.05). Sulfate content was negatively correlated with gel strength (P<0.05).

      Gel strength, agar yield and sulfate content showed monthly variation. Sulfate was highly correlated with gel strength (P<0.05). Agar yield was positively correlated with month, while it is negatively correlated with gel strength (P<0.05).

      The results showed that agar from Gracilariopsis heteroclada has a very good potential for use as raw material for the production of food, drug and industrial grades of agar because of its superior gel strength.
    • Conference paper

      The Agusan Marsh - two years after Pakse 

      JH Primavera - In Proceedings of the Joint Regional Seminar of the Ecotone-SeaBRnet 2007 and the 9th Conference of the China Biosphere … Sustainable Development, Maolan Biosphere Reserve, Libo County, Guizhou Province, P. R. China, 7-12 November 2007, 2008 - UNESCO Office
    • Conference paper

      The Agusan Marsh and the Agusan River Basin: The need for science-based development and management 

      JH Primavera - In MLC Aralar, AS Borja, AL Palma, MM Mendoza, PC Ocampo, EV Manalili & LC Darvin (Eds.), LakeCon2011: Building on the pillars of Integrated Lake Basin Management (Second National Congress on Philippine Lakes), 2013 - PCAARRD-DOST
      Series: Summary of Proceedings No. 1/2013
    • Conference paper

      The Agusan marsh: A situationer with focus on scientific aspects 

      J Primavera & MI Tumanda Jr. - In J Primavera (Ed.), Proceedings of the 1st Scientific Conference on the Agusan Marsh: Butuan City, Agusan del Norte, Philippines, 21-23 May 2007, 2008 - UNESCO Jakarta Office, Philippine Council for Aquatic and Marine Research and Development
      The Agusan Marsh is an extensive floodplain in the middle of the Agusan River Basin in eastern Mindanao where rivers, creeks and tributaries mainly in the provinces of Agusan del Norte, Agusan del Sur and Compostela Valley converge and drain northward to the Agusan River and into Butuan Bay. The main habitats of the Marsh are the freshwater swamp forest (with Terminalia, peat swamp and sago palm forest subtypes), secondary scrub, herbaceous swamp, open water (oxbow/floodplain lakes, pools), and flowing water (rivers, streams). Peat forests have been confirmed in Bunawan and Caimpugan. Over 200 bird species have been known to spend at least part of the year in the Marsh, making it an important site for migratory birds from northern Asia and Siberia. As one of the Philippines' ecologically significant wetlands, the Marsh has been declared a protected site under NIP AS (1994), Presidential Proclamation 913 (1996), and RAMSAR (1999). The Agusan Marsh Wildlife Sanctuary covers -111,540 ha in 8 municipalities of Agusan del Sur. Recently the Agusan Marsh was placed high on the list of Philippine nominations to the World Heritage Natural Sites. Despite all these, very few scientific studies have been conducted on the Marsh but this has not stopped drainage and development for agriculture, construction of dams and reservoirs for irrigation, deliberate or accidental introductions of exotic species, e.g., tilapia, carps, janitor fish, and golden apple snail, and logging in the watershed areas. The latter have been legitimized by Integrated Forest Management Agreements despite the presence of primary forests. The latest proposed intervention is the Agusan River Basin Development Project. There is need for scientific research to provide baseline information on hydrology, sediment dynamics and ecology as prerequisite to any interventions and developments in the Agusan Marsh.
    • Conference paper

      Amino acid and fatty acid profiles in aquaculture nutrition studies 

      LV Benitez - In SS De Silva (Ed.), Fish Nutrition Research in Asia: Proceedings of the Third Asian Fish Nutrition Network Meeting, 6-10 June 1988, Bangkok, Thailand, 1989 - Asian Fisheries Society
      The amino acid profile is an important parameter in the evaluation of protein quality and in requirement studies. Amino acid profiles are usually determined in 2 steps: hydrolysis of the protein to constituent amino acids followed by quantitative analysis of the amino acids in the hydrolysate. The 10 amino acids known to be essential in most animals have been found to be essential in all fish so far studied. The reference amino acid profiles used in the amino acid requirement studies of various fish species include that of whole chicken, egg, fish egg and fish muscle. The amino acid profile of fish muscle provides a useful first approximation of the amino acid requirement of the young, growing fish in which the greatest proportion of weight gain is in the form of muscle.
    • Conference paper

      Anthropological study on the coastal fisheries: harmonization of present and traditional technologies for sustainable coastal fisheries through community-based coastal resources management (CB-CRM): the Philippine experience. 

      EEC Flores - 1996 - Master’s Program in Environmental Sciences, University of Tsukuba
      As an archipelago country, communities in the Philippines grow along the coastal areas, and usually near a river. The main source of food and livelihood of these communities would be from their surrounding aquatic resources. Through the years, some communities grew to become the present day towns and cities or urban centers. With population growth, new communities are formed along the coastal areas along with old communities remaining as such through the years and still depending mainly from the surrounding aquatic resources for food and livelihood.

      This paper will concentrate its presentation on these small communities which are called "barangay", the basic political unit in the Philippines, governed by a Barangay Council headed by a Barangay Captain, who together with its members are elective government officials. The coastal barangay is referred to as the fishing community with its fishers referred to as "municipal" fishermen, or small-scale fishermen. The Philippine Local Government Code defines the fishing area for municipal fishermen as that body of marine water extending 15 kilometers seaward starting from the coastline. Fishing operations with the use of fishing vessels of three gross tons or less can operate in this fishing area or municipal fishing ground.

      Fish production from municipal fisheries have been increasing through the years until 1991 when production continuously decreased up to 1994. Government projections predict the municipal fisheries production up to 1998 at the 1994 level. The main causes for the decrease in municipal fisheries production are illegal fishing operation such as dynamite fishing, "muro-ami" fishing, and cyanide fishing, and overfishing as a result of growing population of fishers and number of fishing communities.
    • Conference paper

      Antibiotic uptake of the giant freshwater prawn Macrobrachium rosebergii by the osmotic infiltration technique. 

      AT Llobrera & DH Lewis - In JL Maclean, LV Dizon & LV Hosillos (Eds.), The First Asian Fisheries Forum. Proceedings of the First Asian Fisheries Forum, 26-31 May 1986, Manila, Philippines, 1986 - Asian Fisheries Society
      Erythromycin and oxytetracycline uptake by the giant freshwater prawn, Macrobrachium rosenbergii , was evaluated by the two-step osmotic infiltration technique. Test prawns were immersed in 7.5% NaCl conditioning (hyperosmotic) solution for 30 min. then transferred to a freshwater (hypo-osmotic) solution containing 10 mu g/ml of antibiotic. Antibiotic uptake was determined in test and control prawns at 5, 10, 20 and 40 min. Maximum concentration of erythromycin was observed in test prawns 10 min. after exposure, whereas the same concentration was not achieved in control prawns until 40 min. Oxytetracycline uptake was similar in treated and control prawns in that maximum tissue levels were observed after 40 min. in both cases. The uptake of erythromycin was significantly greater in prawns treated for 10 min. than in prawns treated for 5, 20 and 40 min. Osmotic infiltration did not significantly enhance oxytetracycline uptake at all time intervals tested.
    • Conference paper

      Antimicrobial resistance in bacteria isolated from aquaculture environments in the Philippines 

      EA Tendencia & CR Lavilla-Pitogo - In Proceedings of the International Workshop: Antibiotic Resistance in Aquaculture Environments, 24-25 February 2005, Chiang Mai, Thailand, 2005 - ASIARESIST
      Antibiotics have been used in aquaculture as feed additives to promote growth and added in water to prevent disease occurrence. Therapeutic doses are used to treat diseases. Long-term use and misuse of antibiotics may result to drug resistant bacterial strains and accumulation of unwanted residues in the cultured commodity upon slaughter and harvest. Some of the antibiotics that have been used in shrimp hatcheries and grow-out ponds are tetracycline, rifampicin, chloramphenicol, nitrofurans, erythromycin, oxolinic acid and furazolidone. Oxytetracycline, furanace, terramycin, Ektecin, chloramphenicol and sulfa drugs have been used to treat fish bacterial infections. Antibiotic resistant bacteria have been isolated from shrimp rearing water, natural bodies of water that received effluents from aquaculture, and from cultured apecies in the Philippines. Resistance to oxytetracycline and furaltadon were reported in bacteria isolated from crab and nearshore sediments. Bacteria from shrimp ponds have been reported to be resistant to oxytetracycline, furazolidone, oxolinic acid and chloramphenicol. Luminous vibrios from shrimp larvae and ponds were resistant to erythromycin, kanamycin, oxytetracycline, Penicillin, streptomycin, sulfadiazine and triple sulfa. Aeromonas sp. from fish, shrimp, and their rearing water were resistant to streptomycin, oxytetracycline and trimethoprim/sulphamethoxazole. Multiple antibiotic resistance has also been reported in bacteria isolated from shrimp, shrimp ponds, luminous bacteria from shrimp post larvae, and Aeromonas hydrophila from fish. Despite the recorded usage, antibiotic residues in cultured food fish have not yet been a problem of the Philippine aquaculture industry as far as trade is concerned. However, chloramphenicol and nitrofurazolidone residues have been detected in shrimp for export using the enzyme link immunoassay (ELISA) technique.

      To minimize the use of antibiotics, different alternative methods to prevent diseases in aquaculture have evolved. Government agencies also issued regulations on the use of antibiotics.
    • Conference paper

      Application of engineering scale-up principles in aquaculture 

      RR Platon - In Report of the National Consultative Meeting on Aquaculture Engineering, 2-5 October 1985, Philippines, 1986 - ASEAN/UNDP/FAO Regional Small-Scale Coastal Fisheries Development Project
      The effects of water movement or agitation on the biological performance of planktonic organisms under intensive culture have been rarely studied quantitatively. Stagnation or minimum values are considered important in the problem of scale-up based on optimum conditions. Near stagnation, inadequate water movement brings about undesirable effects, e.g. accumulation of metabolites, uneven distribution of feed and low dissolved oxygen concentration. An important mechanism associated with water movement at these conditions is the oxygenation process which defines the oxygen transfer rate from the gas to the water.

      Experiments were conducted using potable water to determine the overall oxygen mass transfer coefficient in two types of container geometries: a) cylindri-conical tank and b) oblong-shaped center-partitioned raceway. For each type of container, three geometrically similar sizes were investigated with scale ratio of approximately 1:2:3:5. Agitation was induced by the introduction of air into the system. General correlations for both tank geometries were obtained from experimental data and were expressed in terms of the operating and geometric parameters. The correlations are in the form of dimensionless groups (Froude and Reynolds numbers) making them appropriate for scale-up estimates.

      The general correlations for the overall oxygen mass transfer coefficient were subsequently used to provide the scaling equations to define the operating parameters in different sizes of containers for the culture of brine shrimp in sea water fed with rice bran. The high correlation coefficient obtained for the relationship between total brine shrimp biomass production and the overall mass transfer coefficient applicable to different sizes of both the cylindri-conical tank and the raceway indicates that the overall oxygen mass transfer coefficient is an effective scale-up criterion in brine shrimp culture.
    • Conference paper

      Aqua-mangrove integrated farming: shrimp and mud crab culture in coastal and inland tidal flats with existing reforested or natural growth of mangroves 

      AT Triño - 2000
      Throughout the tropics, mangroves are being destroyed at an increasing rate for the development of aquaculture ponds. In the Philippines, for instance, mangroves were about 400,000 to 500,000 ha in 1918 but were reduced to 100,564 ha in 1987. On the average, about 3,500 ha of mangroves are lost every year in the country to accommodate the aquaculture industry (Baconguis et al., 1990). Loss of mangroves means loss of habitat, fishery, income, and livelihood for many coastal inhabitants. The annual catches of major fishing grounds in the Philippines were positively correlated with the areas of existing mangroves (Bagarinao, 1998). Restoration programs of the government such as mangrove reforestation and afforestation were attempted but could not catch up with the unending destruction. An alternative source of income which is directly supportive of resource management was therefore proposed to mitigate ecosystem degradation with the fisher communities in mind.

      Fishing villages in the Philippines are generally located in the fringes of arable land along coastal plains and are dependent on fishing as a source of income. The common denominator of these villages is the presence of large areas of tidal flats with existing mangroves. To utilize the aquaculture potential of these mangroves, aqua-mangrove integrated farming development projects were introduced to provide alternative livelihood for the fishers in the village. This integrated approach to conservation and utilization of mangrove resource allows for maintaining a relatively high level of integrity in the mangrove area while capitalizing on the economic benefits of brackishwater aquaculture. The projects took off from the concept of co-management, that is, taking into account the partnership between the local community, the local government unit, and the SEAFDEC Aquaculture Department (SEAFDEC/AQD) in the management of the project.
    • Conference paper

      Aquaculture and the coastal environment 

      JH Primavera - In AC Alcala & MC Balgos (Eds.), Management of Nearshore Fishery Resources. Proceedings of the Seminar-Workshop on Management of Nearshore Fishery Resources, 23-25 January 1990, Cebu City, Philippines, 1991 - Philippine Council for Aquatic and Marine Research and Development
      Series: PCAMRD Book Series; No. 10/1991
      Philippine aquaculture production mostly comes from pond culture (brackishwater) constituting 47% of the total 1987 production of 560,970 t followed by mariculture of seaweeds, mollusks and finfishes. Fishponds have increased from around 61,000 ha in 1941 to 210,400 ha at present while the 130,000 ha of remaining mangroves constitute only 13-26% of the original area.

      The effects of aquaculture on the coastal environment are apparent in the decline in nearshore fisheries production and loss of services (typhoon buffer, flood control, soil stabilization). Mangrove conversion into ponds, species introductions and transplantations, spread of parasites, pests and diseases, increased organic nutrient loading, use and release of chemicals, sedimentation, extraction of groundwater, and salinification of soil and water supplies, are the identified aquaculture-related practices that lead to the degradation of nearshore resources. Some ecological effects also have social repercussions.

      Recommended measures to solve these problems include: rationalized use of mangroves and mangrove reforestation; regulation of groundwater extraction, import/ use of chemicals, disposal of organic wastes, and introductions/transplantations; research (bacteriology of aquaculture facilities, effects of organic wastes, effects of sedimentation, effects of chemicals on marine organisms including antibiotic resistance, etc.); training and extension; and improvement of interagency coordination.
    • Conference paper

      Aquaculture industry profile and trends 

      WG Yap - In Fishlink 2001, 29-31 May 2001, Iloilo City, Philippines, 2001 - University of the Philippines Aquaculture Society, Inc.