Now showing items 1-5 of 5

    • 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

      Effects of DHA-enriched live food on growth, survival and incidence of opercular deformities in milkfish (Chanos chanos) 

      RSJ Gapasin & MN Duray - Aquaculture, 2001 - Elsevier
      The use of commercial enrichers to improve the nutritional quality of live food in larviculture of milkfish was investigated. Fish were either fed rotifers cultured on Chlorella sp. and newly hatched Artemia nauplii (Control, Trt I) or rotifers and Artemia given DHA enrichment diets (DHA-treated, Trt II).

      Results showed survival was significantly better (P<0.05) in the DHA-treated fish than in the untreated fish after 25-day culture period. Although growth was not statistically different (P>0.05) between the control and DHA-treated fish during the hatchery phase, extensive rearing of the postlarvae (fry) in nursery ponds for another 60 days showed that DHA-treated fish exhibited significantly better (P<0.05) growth than the untreated fish. Opercular deformities in 85-day old milkfish juveniles were also significantly lower (P<0.05) in the DHA-treated fish than the control. Survival after nursery culture, however, was high for both treatments but not significantly different (P>0.05).

      The lack of a viable and reliable method of mass culturing copepods as live food in the hatchery makes the use of off-the-shelf commercial enrichment diets for rotifers and Artemia a practical option in the larval culture of milkfish.
    • 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.
    • Article

      Nutritional evaluation of mysids Mesopodopsis orientalis (Crustacea:Mysida) as live food for grouper Epinephelus fuscoguttatus larvae 

      PS Eusebio, RM Coloso & RSJ Gapasin - Aquaculture, 2010 - Elsevier
      The potential of mysids Mesopodopsis orientalis as live food source for grouper Epinephelus fuscoguttatus larvae was investigated. In comparison with Artemia biomass, a common live food source in larviculture, mysids contained significantly higher levels of protein, total lipid, eicosapentaenoic acid (EPA, C20:5n−3), and docosahexaenoic acid (DHA, C22:6n−3). DHA was not detected in Artemia biomass. Grouper larvae fed mysids from 35 to 55 days after hatching (DAH) had 2-fold and 3-fold higher specific growth rates and survival, respectively, than those fed Artemia biomass. DHA levels increased 6-fold while EPA levels remained constant in mysid-fed grouper larvae. In contrast, DHA and EPA significantly decreased in Artemia biomass-fed grouper larvae. Furthermore, the specific activities of amylase, lipase and protease generally significantly increased (P< 0.05) in both mysid-fed and Artemia biomass-fed grouper larvae from 35 to 55DAH. A marked increase in the specific activity of amylase was seen in mysid-fed than in Artemia biomass-fed grouper larvae. Results of the nutritional evaluation suggest that mysids are superior live food organisms than Artemia biomass for grouper larvae and could significantly improve production of grouper juveniles in the nursery phase.
    • 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.