Now showing items 1-3 of 3

    • Article

      Dietary lipid requirement of whiteleg shrimp Litopenaeus vannamei juveniles cultured in biofloc system 

      A Hamidoghli, S Won, FA Aya, H Yun, J Bae, IK Jang & SC Bai - Aquaculture Nutrition, 2019 - Wiley
      An eight-week feeding trial was conducted to evaluate the contribution of biofloc on dietary lipid requirement in whiteleg shrimp Litopenaeus vannamei. Five diets with graded levels of dietary lipid (45, 60, 90, 120 and 150 g/kg) were fed to juvenile shrimp. Final weight, weight gain and specific growth rate of shrimp fed diets with 60, 90 and 120 g/kg lipid levels were significantly higher than those of shrimp fed diets with lipid levels 45 and 150 g/kg (p < .05). Feed efficiency and protein efficiency ratio of shrimp fed 60, 90 and 120 g/kg were higher than those fed 150 g/kg diet. Plasma total cholesterol and triglyceride levels were lower in shrimp fed 45 g/kg compared with those fed the 90 g/kg (p < .05). Also, lysozyme activity for 90 g/kg group was higher than the 15 g/kg group. Hepatopancreas lipase and amylase activities of shrimp fed 90 and 120 g/kg diets were significantly higher than those of shrimp fed 45 and 150 g/kg diets. Broken-line regression analysis for weight gain indicated that the dietary lipid requirement of whiteleg shrimp juveniles reared in a biofloc system was estimated to be higher than 56 g/kg but <60 g/kg.
    • Article

      Effects of replacing dietary fish oil with beef tallow on growth performance, serological parameters, and fatty acid composition in juvenile olive flounder, Paralichthys olivaceus 

      S Lee, FA Aya, S Won, A Hamidoghli & SC Bai - Journal of the World Aquaculture Society, 2019 - Wiley
      This study evaluated the effects of replacing fish oil (FO) with beef tallow (BT) in juvenile olive flounder, Paralichthys olivaceus (3.93 ± 0.07 g), over 8 weeks. Seven diets, consisting of 0, 25, 50, 75, and 100% replacement of FO with BT and 63 and 75.9% replacement supplemented with docosahexaenoic acid (DHA) at 0.9 and 1.1% of 100 g diet, respectively, were distributed into 21 tanks in a semi‐recirculation system with 15 fish per tank. The replacement of FO with BT at the given levels showed no significant changes (p > .05) in growth performance and whole‐body proximate composition. Fish fed the diet of 75.9% replacement with 1.1% DHA supplementation showed the best performance in these measurements among the treatments. Plasma glutamic pyruvic transaminase, cholesterol, high‐ and low‐density lipoproteins, and total protein were not significantly influenced by the replacement of FO with BT. The FO replacement generally resulted in a reduction of eicosapentaenoic acid, DHA, and n‐3/n‐6 polyunsaturated fatty acid ratio in the whole body, whereas the DHA supplementation recovered the level of DHA and the n‐3/n‐6 ratio to those observed in the group fed the 0% replacement diet. Taken together, BT along with DHA supplementation can potentially be a cost‐effective alternative for FO in olive flounder culture.
    • Article

      Effects of the dietary fermented tuna by-product meal on growth, blood parameters, nonspecific immune response, and disease resistance in juvenile olive flounder, Paralichthys olivaceus 

      FO Oncul, FA Aya, A Hamidoghli, S Won, G Lee, KR Han & SC Bai - Journal of the World Aquaculture Society, 2018 - World Aquaculture Society
      This study evaluated the effects of dietary fermented tuna by‐product meal (FTBM) in juvenile olive flounder, Paralichthys olivaceus. Five diets were formulated to replace fishmeal (FM) with FTBM at 0% (FTBM0), 12.5% (FTBM12.5), 25.0% (FTBM25), 37.5% (FTBM37.5), or 50% (FTBM50). After 8 wk, weight gain, specific growth rate, and feed efficiency of fish fed FTBM0 and FTBM12.5 diets were significantly higher than fish fed the other diets (P < 0.05). Also, mean cumulative survival rates (%) of fish fed the FTBM0 and FTBM12.5 diets were significantly higher than those fed FTBM50 diet at Day 9 postchallenge with Edwardsiella tarda (P < 0.05). Protein efficiency ratio of fish fed FTBM0 and FTBM12.5 diets was significantly higher (P < 0.05) than fish fed diets FTBM37.5 and FTBM50. Broken‐line regression analysis of weight gain showed an optimal FM replacement level of 10.65% with FTBM. Therefore, the optimal dietary inclusion of FTBM in juvenile olive flounder diets could be greater than 10.65% but less than 12.5% without any adverse physiological effects on fish health.