Now showing items 3228-3247 of 3262

    • magazineArticle

      What do you know about siganids? 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1994 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • magazineArticle

      What needs to be done?: Guide in mangrove reforestation 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The article presents a two-part guideline in mangrove reforestation. The first part is zonation, which is the process of determining what species are particularly suited to plant in a particular site. While, plantation establishment is the second part, it includes guides in the identification of species, selection of planting site, preparation of the planting sites, seed collection, handling and transporting of seeds, and planting.
    • magazineArticle

      What species [of snappers] are marketed? 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1992 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • magazineArticle

      What you need to know about sea bass and sea bass farming 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1988 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • magazineArticle

      What you should know about carp: its origin, varieties, physical appearance, feeding habits 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The article discusses the different varieties of carps, their origin, physical appearance and feeding habits. The species discussed were grass carp (Ctenopharyngodon idella), silver carp (Hypophthalmichthys molitrix), bighead carp (Aristichthys nobilis), catla (Catla catla), rohu (Labeo rohita), mrigal (Cirrhinus mrigala, and common carp (Cyprinus carpio).
    • magazineArticle

      What you should know about seaweeds 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1991 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • Flyer

      What's in a tangab? 

      Anon. - 2008 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The flyer contains information about the tangab, which are large fixed filter nets held open by coconut trunks driven into the sea bed, and are operated in Iloilo Strait between Panay Island and Guimaras Island.
    • magazineArticle

      What's up on carp? 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Bighead carp is preferred among other species for culture because of its fast growth and high survival rate. Pen and cage culture of carps in Laguna de Bay is sustained by the availability of juveniles as a result of improved hatchery technology. Southeast Asian Fisheries Development Center and the Bureau of Fisheries and Aquatic Resources have been conducting research programs to enhance the carp culture industry in the country.
    • Article

      White spot syndrome virus (WSSV) risk factors associated with shrimp farming practices in polyculture and monoculture farms in the Philippines 

      EA Tendencia, RH Bosma & JAJ Verreth - Aquaculture, 2011 - Elsevier
      White spot sydrome virus (WSSV) is one of the most important viral disease of shrimp. Several studies to control the disease have been done. Tank experiments identified WSSV risk factors related to the physico chemical properties of the water. A few studies reported pond level WSSV risk factors. This study identifies the risk factors associated with essentially two different farming systems: polyculture and semi-intensive monoculture of Penaeus monodon. Data were gathered from a total of 174 shrimp farmers in eight provinces of the Philippines using a structured questionnaire. Forty-seven variables related to pond history and site description, period of culture, pond preparation techniques, water management, culture methods, feed and other inputs, and biosecurity measures were investigated. In the analysis for combined monoculture and polyculture farms, feeding live molluscs was identified as important WSSV risk factors. In addition to feeding live molluscs, sharing of water source with other farms, having the same receiving and water source, larger pond size, and higher stocking density were identified as important WSSV risk factors in monoculture farms. Climate, i.e. stocking during the cold months and sludge removal and its deposition on the dikes were identified as WSSV risk factors in polyculture farms. Protective factors, listed in decreasing significance, were feeding with planktons and high mangrove to pond area ratio, both observed in the dataset with both monoculture and polyculture farms, while only the latter was observed in the dataset for monoculture farms only. No protective factor was observed in the dataset for polyculture farms.

      This study confirmed the negative effect of sharing water source with other farms and identified several new factors influencing WSSV infection such as feeding live molluscs increases the risk, while feeding with planktons and high mangrove to pond area ratio reduce the risk.
    • magazineArticle

      Whither aquaculture? 

      NJ Dagoon - SEAFDEC Asian Aquaculture, 2000 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • Article

      Why are Halophytophthora species well adapted to mangrove habitats? 

      EM Leaño, EBG Jones & LLP Vrijmoed - Fungal Diversity, 2000 - Springer Verlag
      Halophytophthora species are commonly isolated from fallen mangrove leaves from early to late stages of decay. In this study we show that these organisms are well adpted to mangrove habitats as they have a wide tolerance to varying levels of pH, salinity and temperature. They also produce, abundant zoospores, and are chemotactically attracted to decaying mangrove leaves, and can readily attach to suitable substrata. In general, the four tested isolates (H. vesicula, H. avicennae, H. kandeliae and H. bahamensis) grew at pH 6-9, with maximum growth recorded at neutral pH. Vegetative growth and sporulation were observed over a wide range of salinities (from freshwater to marine) and temperatures, although optimum requirements varied from species to species. Zoospores of Halophytophthora spp. were chemotactically attracted to mangrove leaf-extracts and some other compounds that are common to the surrounding environment. The zoospores attached and germinated on both artificial (glass coverslips and polycarbonate membranes) and natural (mangrove leaves) substrata. Scanning electron micrographs show that newly attached zoospores, cysts, and germinating cystospores of H. vesicula produced fibrillar adhesive mucilage for attachement as was evident by debris sticking to their tips. More adhesive mucilage was produced by encysted and germinating cystospores on natural as compared to artificial substrata. Cystospores and germlings of H. vesicula and H. avicennae were also found to attach firmly to a perspex disc even after being subjected to a high shear stress of 3.19 Newton per square meter (Nm-2). Enzyme treatment and staining of attached cystospores indicate that the adhesive produced is composed of acidic polysaccharide with α-1, 4 linkages, and with either sulphate or phosphate functional groups. Once the cystospores were attached to the substratum, they could not be readily dislodged, and successful germination and colonization followed.
    • magazineArticle

      Why artificial reefs? 

      Southeast Asian Fisheries Development Center, Aquaculture Department - Aqua Farm News, 1991 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • magazineArticle

      Wild milkfish abound in Australia s north coast 

      AP Surtida - SEAFDEC Asian Aquaculture, 1999 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • Conference paper

      Will microbial manipulation sustain the ecological balance in shrimp (Penaeus monodon) hatcheries? 

      CR Lavilla-Pitogo, LJ Albright & MG Paner - In TW Flegel (Ed.), Advances in Shrimp Biotechnology : Proceedings to the special session on shrimp biotechnology, 5th Asian Fisheries Forum, 11-14 November 1998, Chiengmai, Thailand, 1998 - National Center for Genetic Engineering and Biotechnology
      A shift in preferred methods employed to contain bacterial diseases in the hatchery phase of shrimp culture has resulted largely from the unsuccessful control by and deleterious effects of chemotherapy. Manipulation of hatchery microbial ecology has gained popularity, but for successful implementation, this niche-filling approach requires a thorough understanding of the epidemiology of bacterial diseases in the hatchery. This study examined the responses of Vibrio harveyi populations, (associated with luminescent vibriosis in shrimp larvae) to various physico-chemical factors and various hatchery components. Results showed that V. harveyi had a wider range of tolerance to environmental parameters than larvae of Penaeus monodon, such that control measures based on manipulation of these parameters might not be feasible. However, it was evident from the results that there were components in the shrimp hatchery environment that could be manipulated to control high populations of V. harveyi. The natural microflora of seawater, as well as the microbial flora associated with the diatoms Skeletonema costatum and Chaetoceros calcitrans negatively affected the survival of V. harveyi in experimental mixed cultures. The successful manipulation of such benign microbial components to compete with and exclude potential pathogens is necessary to sustain ecological balance in the shrimp hatchery environment.
    • magazineArticle

      The window-pane (kapis shell) industry 

      RIY Adan - SEAFDEC Asian Aquaculture, 2000 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • Article

      Winter distribution of phytoplankton and zooplankton around some sandbanks of the Belgian coastal zone 

      A M'harzi, M Tackx, MH Daro, I Kesaulia, R Caturao & N Podoor - Journal of Plankton Research, 1998 - Oxford University Press
      The distribution of phytoplankton and zooplankton around three sandbanks (Gootebank, Westhinder and Buitenratel sandbank) off the Belgian Coast was investigated in February 1994. The abundance of phytoplankton taxa was significantly different between the sandbanks. Community analysis using TWINSPAN resulted in a clear separation of clusters corresponding to the different sandbanks. The zooplankton community analysis, on the contrary, showed a rather indistinctive division of the sandbank stations. This was due to the omnipresence of three dominant copepod species (Temora longicornis, Pseudocalanus elongatus and Centropages hamatus). When these species were excluded from the analysis, a clearer distinction between the different sandbanks was found. The observed differences in phyto- and zooplankton species distribution could be explained by the position of the sandbanks. Westhinder is positioned further from the coast than Buitenratel, while Gootebank has an intermediate position. Buitenratel and Gootebank harbour typical coastal plankton communities, while the plankton community over Westhinder is clearly influenced by the Atlantic current penetrating the southern North Sea from the English channel. More phyto-benthic species were found at Buitenratel than at Gootebank, probably because of its limited depth. Thus, the Belgian coastal zone, which is considered as one box in most spatial descriptions of the North Sea plankton, in fact harbours heterogeneous plankton communities at the end of winter.
    • Article

      Withdrawal of exogenous 17-alpha methyltestosterone causes reversal of sex-inversed male grouper Epinephelus suillus (Valenciennes) 

      JD Tan-Fermin - The Philippine Scientist, 1992 - San Carlos Publications
      The protogynous hermaphrodite groupers Epinephelus suillus were given bi-weekly injections of 17 alpha-methyltestosterone (MT) intramuscularly for three to six months. Spermatogenesis occurred after three months of MT treatment while spermiation was observed after five to six months of MT treatment in larger fish. Neither cannulated tissue nor milt was obtained when the remaining fish were sampled four months after withdrawal of exogenous MT. However, vitellogenic eggs (size range = 0.34 to 0.56 mm) were cannulated eight months after termination of MT treatment. Presence of eggs in fish which previously had expressible or cannulated milt indicates that the sex-inversed male E. suillus reverted back to the female condition upon withdrawal of exogenous MT. This information is useful in the line production of functional males which is the limiting factor in induced breeding of groupers.
    • Article

      Women and the question of sustainable development in a Philippine fishing village 

      SV Siar & LM Cañeba - International Journal of Sustainable Development and World Ecology, 1998 - Taylor & Francis
      This paper presents a case study of time use and contribution to the household income of men, women, and children in 12 households in a fishing village in Panay Island, central Philippines. The study highlights the differential impact of poverty on men and women and provides a glimpse of the intrahousehold dynamics within poor fishing households. Findings in previous studies in both industrialized and developing countries that women work longer hours than men were corroborated. Women contribute at least 22% to the household cash income and 40% of the value of unpaid labour. Their contribution to the household cash income becomes larger than that of men's when the value of livestock is computed. Women's daily participation in productive activities, such as fish vending and shucking oyster and mussel, unwittingly puts them in a position of being environmental recorders and verifiers of the state of fishery resources. Because they are burdened with the responsibility of making ends meet, they are also confronted with the challenge of realizing the dream of sending their children to university to enable them to escape poverty. This alone makes women one of the strongest stakeholders in the sustainable development of fishery resources.
    • magazineArticle

      Women do fish! 

      Southeast Asian Fisheries Development Center, Aquaculture Department - SEAFDEC Asian Aquaculture, 1999 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • magazineArticle

      Working together to save shrimp 

      J Carreon-Lagoc - Aqua Farm News, 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center