Now showing items 1-6 of 6

    • Article

      Drug assimilation in the tissue of European sea bass (Dicentrarchus labrax) fry delivered orally through bioencapsulation 

      RSJ Gapasin, HJ Nelis, M Chair & P Sorgeloos - Journal of Applied Ichthyology, 1996 - Wiley-Blackwell
      Assimilation levels of the antibacterials trimethoprim (TMP) and sulfamethoxazole (SMX) in sea bass (Dicentrarchus labrax) fry tissue administered orally were investigated. A 1:5 TMP and SMX combination incorporated in an oil emulsion (Selco) at 20 % and 40 % concentrations (w/w) were bioencapsulated in Artemia (Instar II) nauplii. Chemotherapeutics-loaded ('medicated) nauplii were fed to the sea bass fry and drug concentrations in the tissue were analysed by high-performance liquid chromatrography (HPLC). Fish fed 40 %'medicated Artemia assimilated significantly higher levels of chemotherapeutics compared with those fed 20 %'medicated' Artemia. Chemotherapeutics given at 40 % reached peak levels (19.3 μg TMP/g DW and 23.31 μg SMX/g DW) within 2 h while those at 20 % peaked (8.74 μg TMP/g DW and 6.73 fig SMX/g DW) after 5 h. TMP persisted in the tissues longer (up to 72 h) than SMX (12–16 h), suggesting a more efficient uptake and retention of the former and/or faster metabolism and elimination of the latter.
    • Article

      Enrichment of live food with essential fatty acids and vitamin C: effects on milkfish (Chanos chanos) larval performance 

      RSJ Gapasin, R Bombeo, P Lavens, P Sorgeloos & H Nelis - Aquaculture, 1998 - Elsevier
      The effects of essential fatty acids (EFA) and vitamin C-enriched live food on growth, survival, resistance to salinity stress and incidence of deformity in milkfish larvae reared in tanks were investigated. Larvae were either fed rotifers cultured on Chlorella sp. and newly hatched Artemia nauplii (control), highly unsaturated fatty acid (HUFA)-enriched rotifers and Artemia nauplii or HUFA+vitamin C-enriched rotifers and Artemia nauplii. Milkfish growth in outdoor nursery ponds was also assessed to compare with growth in indoor tanks. Milkfish fed rotifers/Artemia enriched with HUFA (32–48 mg dry weight, DW) or HUFA+vitamin C (33–45 mg DW) exhibited significantly (P<0.05) higher growth than those given unenriched live food (24–27 mg DW) after 40 days of culture. Growth of milkfish in nursery ponds (albeit lower in stocking density) showed similar trends as those reared in tanks. When subjected to salinity stress (Day 25), mortality of the HUFA+vitamin C-treated fish and HUFA-treated fish were significantly lower (P<0.05) than the control fish. Survival of 26-day old milkfish, however, did not differ significantly (P>0.05) among the treatment groups. Forty-day-old milkfish fed HUFA+vitamin C-enriched live food had significantly lower (P<0.05) incidence of opercular deformity (mainly cleft branchiostegal membrane) (8.4–14.7%) compared with those given HUFA-enriched (15.8–23.5%) or unenriched (27.3–33.5%) live food. Results demonstrated the effect of HUFA enrichment in enhancing milkfish larval growth and resistance to salinity stress but not overall survival. Moreover, HUFA and ascorbate supplementation decreased but did not totally eliminate incidence of opercular deformity in milkfish larvae.
    • Conference paper

      Oral administrations of chemotherapeutics via the bioencapsulation technique: A tool for therapeutic treatment in larviculture 

      RSJ Gapasin, HJ Nelis & P Sorgeloos - In CL Marte, GF Quinitio & AC Emata (Eds.), Proceedings of the Seminar-Workshop on Breeding and Seed Production of Cultured Finfishes in the Philippines, Tigbauan, Iloilo, Philippines, 4-5 May 1993, 1996 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The application of the bioencapsulation technique as a tool for curative treatment in fish larvae was investigated. Antibacterials, trimethoprim (TMP) and sulphamethoxazole (SMX), incorporated in an oil emulsion (SELCO, Artemia Systems N.V., Ghent, Belgium) were bioencapsulated at different concentrations (20% and 40%) in Artemia (Instar II) nauplii. Chemotherapeutics-loaded nauplii were fed to European sea bass (Dicentrarchus labrax) larvae only once at 5 individuals/ml. Larvae were sampled after feeding at time intervals 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 12, 16, 20, 24, 36, 48, 60, 72 h. Drug concentrations in the larval tissue were analyzed by high-performance liquid chromatography (HPLC). Results indicated that larvae fed 40% "medicated"-Artemia assimilated significantly higher levels of chemotherapeutics in the tissue as compared with those fed 20% "medicated"-Artemia. Chemotherapeutics given at higher concentration (40%) reached peak levels (19.3 µg TMP/g DW, 23.32 µg SMX/g DW) in the larval tissues within 2 h while at lower concentration (20%) peak levels (8.74 µg TMP/g DW, 6.73 µg SMX/g DW) were observed within 5 h. Moreover, TMP persisted longer (>72 h) in the tissues than SMX (12-16 h) suggesting a more efficient uptake and retention of TMP and/or faster metabolism and elimination of SMX.
    • Article

      A simple semi flow-through culture technique for the controlled super-intensive production of Artemia juveniles and adults 

      P Dhert, RF Bombeo, P Lavens & P Sorgeloos - Aquacultural Engineering, 1992 - Elsevier
      A simple semi flow-through Artemia culture unit is described for possible integration in marine fish and shellfish hatcheries as source of a cheap nursery diet. The system does not require the use of feeding pumps and involves minimal care. Food preparation and addition to the feeding tank is reduced to one or two manipulations per day during the meta-nauplius stages (day 1–3) and the juvenile stages (day 4–14), respectively.

      Biomass productions are superior to those reported for stagnant culture systems and are comparable to those demonstrated for flow-through culture units. This simple rearing technique offers the possibility of producing brine shrimp populations with a uniform size. Furthermore, by varying the feeding regime with the Artemia density at the start of the culture, specific Artemia prey sizes corresponding to the daily physical requirements in shrimp and fish hatcheries can be obtained.
    • Article

      Successful inoculation of Artemia and production of cysts in man-made salterns in the Philippines 

      C Delos Santos Jr., P Sorgeloos, E Laviña & A Bernardino - SEAFDEC Aquaculture Department Quarterly Research Report, 1979 - Aquaculture Department, Southeast Asian Fisheries Development Center
      The authors report on inoculation experiments of Artemia nauplii and young adults of the San Francisco Bay strains in earthen fish ponds. The test inoculated proved successful where water salinity ranges from 20 to 32 ‰ during the start of the rainy season in the Philippines.
    • Article

      Vaccination of European sea bass fry through bioencapsulation of Artemia nauplii 

      M Chair, RSJ Gapasin, M Dehasque & P Sorgeloos - Aquaculture International, 1994 - European Aquaculture Society
      European sea bass (Dicentrarchus labrax) fry vaccinated orally via bioencapsulation in Artemia nauplii or by bath method exhibited better performance than control fish in terms of growth, food conversion and resistance to stress. The comparable survival between vaccinated and non-vaccinated animals suggests that vaccination methods are not stressful. The present study shows that oral vaccination can be used to enhance growth in fish fry.