Now showing items 1-5 of 5

    • Conference paper

      Cage culture of Kappaphycus alvarezii (doty) doty and Epinephelus sp. 

      AQ Hurtado-Ponce - In PM Aliño (Ed.), Proceedings of the Second National Symposium in Marine Science, 5-7 November 1992, Mindanao State University, Tawi-tawi, Philippines, 1994 - University of the Philippines, Marine Science Institute
      Kappaphycus alvarezii seedlings were cultured in cluster, vertically and horizontally using nylon monofilament rope attached to a bamboo raft installed inside a 5 x 5 m floating cage. Juveniles of Epinephelus sp. were stocked as biological control to grazers.

      Specific growth rate (% increase in weight day-1) and production (g m-1 line-1) of Kappaphycus were determined every 45 days and production of Epinephelus was determined after 120 days. Specific growth rate of Kappaphycus alvarezii was significantly affected by the culture technique used. An average specific growth rate of 3.7 %, 3.8 % and 5.3 % was recorded when K alvarezii was cultured in clusters, vertically and horizontally in that order. Horizontal technique of culturing K alvarezii was significantly different from vertical and cluster techniques (DMRT = 0.05). Production (g m-1 line-1) of K. alvarezii ranged from 766 to 1,970, (in clusters), 1,110 to 1975 (vertically) and 1,204 to 1,533 (horizontally). These values were significantly affected by the culture month but insignificantly affected by culture technique (DMRT = 0.05). After 120 days of culture, mean weight of Epinephelus sp. was 297 g; % weight gain cage-1 was 233; survival rate = 68 %; fish production = 5 kg; and FCR = 6.
    • Conference paper

      Kappaphycus and Gracilariopsis meal as binders for diets of tiger shrimp 

      V Peñaflorida & N Golez - 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Two locally grown seaweeds, Kappaphycus alvarezii and Gracilaria heteroclada, were tested as binders in diets for shrimp juveniles to minimize the use of wheat flour, a common binder. The seaweeds were washed, dried, ground, and made into paste. Seaweed meals were added to an isonitrogenous diet containing 5% flour at 5, 10 and 15%. The control diet contained 15% flour (no seaweed meal). The diets were fed to juvenile Penaeus monodon for 56 days to assess the acceptability of the seaweed meals in terms of shrimp growth, survival and feed conversion ratio (FCR). Seven dietary treatments, each with three replicates, were arranged in a completely randomized design. Treatment means were compared by analysis of variance and Duncan's multiple range test.Growth of shrimp fed diets with 5% and 10% G. heteroclada, and 10% K. alvarezii did not differ significantly but was higher than the rest of the treatments. Only those fed 10% G. heteroclada had growth similar to those fed the control diet. Diets with 5% and 10% K. alvareziii and 10% G. heteroclada had the best FCR. Shrimp survival decreased as the level of G. heteroclada increased. Survival was not affected by the level of K. alvarezii in the diet.Water stability of the diets was assessed in 4 h. High water stability was observed in the diet with 10% G. heteroclada (91%), 5% G. heteroclada (90%) and the control (90%). The rest of the diets were 87-89% stable. Thus, 10% G. heteroclada or 10% K. alvarezii could be used to supplement 5% flour as binders in shrimp diets with no adverse effect on growth and survival.
    • Conference paper

      Research on seaweeds and mollusks 

      AQ Hurtado-Ponce - In TU Bagarinao & EEC Flores (Eds.), Towards sustainable aquaculture in Southeast Asia and Japan: Proceedings of the Seminar-Workshop on Aquaculture Development in Southeast Asia, Iloilo City, Philippines, 26-28 July, 1994, 1995 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Research on seaweeds focused on the carrageenan-producing Kappaphycus alvarezii and the agar-producing Gracilaria spp. Growth of K. alvarezii was better on horizontal lines than on vertical or cluster lines from bamboo rafts. All morphotypes (brown green, and red) grew faster at 50 cm than at 100 cm below the water surface, but the green morphotype showed better carrageenan properties. A socioeconomic survey of K. alvarezii farming in Panagatan Cays, Antique revealed that a farmer has an average annual production of 3 tons/ha (dry) with the fixed bottom and hanging longline methods.

      Three species of Gracilaria in natural beds in lloilo showed monthly variations in biomass and agar quality; G. heteroclada had the highest biomass and gel strength. When this species was grown in tanks, growth and agar sulfate content were influenced by the interaction of light, salinity, and nutrients. Enriched and unenriched stocks of G. heteroclada differed in agar quality. When G. heteroclada was grown with the tiger shrimp Penaeus monodon in extensive ponds, the highest growth rate and production were obtained at the seaweed stocking density of 250 g/m2; this was in November when average water temperature, transparency, and salinity were low. Salinity tolerance varies among Gracilaria species.Oyster (Crassostrea iredalei) and mussel (Perna viridis) farming in Western Visayas were assessed in 1992 in terms of the culture methods, socioeconomics, marketing, and profitability. A more localized survey of oyster and mussel fanning was conducted through rapid rural appraisal in two coastal towns in 1993. A farmer-participatory study followed in 1994 for the culture of oysters, mussels, seaweeds, and rabbitfishes in a river mouth in Dumangas, lloilo. Green mussel, brown mussel (Modiolus metcalfei), and seaweeds transplanted to Dumangas from Capiz have reproduced. In another study, the green mussel was tested as a biological filter in tiger shrimp ponds; shrimps stocked with mussels grew better than those without.

      A nationwide survey on the Placuna placenta fishery in 1993 showed 27 remaining 'kapis' beds; many others have been depleted due to excessive gathering, pollution, siltation, and trawling. Broodstocks are being developed to produce 'kapis' seed for grow-out and restocking. For the first time at AQD, adult donkey-ear abalone Haliotis asinina from the wild spawned naturally in laboratory tanks.

      Juvenile abalones can be successfully grown on Gracilaria or abalone diet.
    • Conference paper

      Status of seaweed farming in Region 6 

      RST Hablo - 2002 - Aquaculture Department, Southeast Asian Fisheries Development Center
    • Conference paper

      Status of seaweed farming in Region 9 

      HH Kalbi - 2002 - Aquaculture Department, Southeast Asian Fisheries Development Center