Now showing items 1-14 of 14

    • Article

      Diet composition, feed preferences and mouth morphology of early stage silver therapon (Leiopotherapon plumbeus, Kner 1864) larvae reared in outdoor tanks 

      FA Aya, MNC Corpuz & LMB Garcia - Journal of Applied Ichthyology, 2015 - Wiley
      This study examined the diet composition, feeding preferences, and mouth morphology of the silver therapon (Leiopotherapon plumbeus, Kner 1864) larvae under captive conditions. Larvae were reared in outdoor tanks (4 m3) with natural food grown 2 weeks prior to start of larval rearing. Food preference was measured by the Chesson's electivity index (αi). Gut content analysis of larvae sampled between 5 and 25 days after hatching (DAH) showed the dominance in the diet by zooplankton, mainly copepod nauplii, cladocerans and insect larvae. Small fish larvae (5–9 DAH; 3.32–6.29 mm standard length) preferred cladocerans, ciliates and copepod nauplii; whereas older larvae (12–25 DAH; 5.45–19.26 mm standard length) preferred insect larvae over cladocerans and adult insects. The mouth gape size at 5 DAH was 359 μm and increased to 3.75 mm at 40 DAH when body size grew at an average rate of 0.59 mm d−1. The standard length (SL) of L. plumbeus larvae was strongly associated with mouth size (r2 = 0.98, P < 0.05), indicating a progressive increase of ingested prey size of the fish larvae. These results clarified the early life feeding ecology of this species, which is essential in developing effective hatchery techniques.
    • Article

      Dietary P regulates phosphate transporter expression, phosphatase activity, and effluent P partitioning in trout culture 

      RM Coloso, K King, JW Fletcher, P Weis, A Werner & RP Ferraris - Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology, 2003 - Springer Verlag
      Phosphate utilization by fish is an important issue because of its critical roles in fish growth and aquatic environmental pollution. High dietary phosphorus (P) levels typically decrease the efficiency of P utilization, thereby increasing the amount of P excreted as metabolic waste in effluents emanating from rainbow trout aquaculture. In mammals, vitamin D3 is a known regulator of P utilization but in fish, its regulatory role is unclear. Moreover, the effects of dietary P and vitamin D3 on expression of enzymatic and transport systems potentially involved in phosphate utilization are little known. We therefore monitored production of effluent P, levels of plasma vitamin D3 metabolites, as well as expression of phosphatases and the sodium phosphate cotransporter (NaPi2) in trout fed semipu diets that varied in dietary P and vitamin D3 levels. Mean soluble P concentrations varied markedly with dietary P but not with vitamin D3, and constituted 40–70% of total effluent P production by trout. Particulate P concentrations accounted for 25–50% of effluent P production, but did not vary with dietary P or vitamin D3. P in settleable wastes accounted for <10% of effluent P. The stronger effect of dietary P on effluent P levels is paralleled by its striking effects on phosphatases and NaPi2. The mRNA abundance of the intestinal and renal sodium phosphate transporters increased in fish fed low dietary P; vitamin D3 had no effect. Low-P diets reduced plasma phosphate concentrations. Intracellular phytase activity increased but brushborder alkaline phosphatase activity decreased in the intestine, pyloric caeca, and gills of trout fed diets containing low dietary P. Vitamin D3 had no effect on enzyme activities. Moreover, plasma concentrations of 25-hydroxyvitamin D3 and of 1,25-dihydroxyvitamin D3 were unaffected by dietary P and vitamin D3 levels. The major regulator of P metabolism, and ultimately of levels of P in the effluent from trout culture, is dietary P.
    • Article

      Genotype environment interaction in the response of three strains of Nile tilapia to poor nutrition 

      MRR Romana-Eguia & RW Doyle - Aquaculture, 1992 - Elsevier
      Experiments were conducted to determine the effects of poor nutrition on the growth of three Oreochromis niloticus strains fed protein-deficient diets. Four-week-old fry from the three "test" strains were paired with a fourth "reference" strain of tilapia (red) of the same size and stocked in 60-1 aquaria. The treatment lasted 6 weeks, with fish being fed commercial fish feed crumbles for the first and last 2-week periods and rice bran during weeks 3 and 4. Control fish were fed commercial diet throughout. Both control and treatment fish were fed at 20% of fish biomass per day. Lengths and weights were measured every 2 weeks.

      Significant strain effects were noted when the growth of test fish over the whole experimental period was analysed by analysis of covariance using the reference fish growth as a concomitant variable. The relative growth of the three test strains differed at each feeding phase. The NIFI strain grew best during the commercial feed phases, the Israel strain performed best during the rice bran phase while the CLSU strain, regardless of the type of nutritional environment, usually ranked last. Different performance rankings at each feeding phase represent strong genotype X environment interaction among these commercially important lines. This was statistically confirmed by analysis of covariance of the growth of the Israel and NIFI strains during the different feeding phases using the reference strain as a covariate.
    • Article

      Growth, survival and macronutrient composition of Penaeus monodon Fabricius larvae fed with Chaetoceros calcitrans and Tetraselmis chuii 

      E Tobias-Quinitio & CT Villegas - Aquaculture, 1982 - Elsevier
      Penaeus monodon larvae were reared from zoea1 (Z1) to mysis3 (M3) using two different algal feeds, Chaetocero calcitrans and Tetraselmis chuii. Artemia nauplii were added to both treatments at mysis2. Mean survival and growth rates in both treatments were different at 5% level of significance on the second and third day of culture, but did not differ during the mysis stage and the end of the 8-day culture period.

      Z3 and M3 larvae fed with C. calcitrans had a lower crude protein but a higher lipid content than T. chuii-fed larvae. Differences in carbohydrate content were noticed in M3 larvae. The implication of the findings are discussed.
    • Article

      Influence of nutrition on the hepatocytes of Chanos chanos (Chanidae: Teleostei) 

      V Storch, H Segner, JV Juario & MN Duray - Zoologischer Anzeiger, 1984 - Elsevier
      The hepatocytes of milkfish (C. chanos) fry and fingerlings offered a variety of diets differ considerably as was shown by means of transmission electron microscopy. For fry it was shown that a 7 day starvation period results in a heavily altered hepatocyte ultrastructure but that even in this stadium fast regeneration was possible. Chlorella turned out to be the worst diet, among the artificial diets, the trout diet provoked the best regeneration. In fingerlings a prolonged starvation period was necessary to affect hepatocytes. In some cases considerable indications of liver cell degeneration were found after feeding certain diets for 2-3 months. Even dried lumut and lab-lab did not create optimal hepatocyte ultrastructure. Feeding with cod liver oil did not result in deposition of lipid droplets in the hepatocytes of fingerlings, what is in contrast to milkfish fry hepatocytes.
    • Article

      mRNA expression patterns for GH, PRL, SL, IGF-I and IGF-II during altered feeding status in rabbitfish, Siganus guttatus. 

      FG Ayson, EGT de Jesus-Ayson & A Takemura - General and Comparative Endocrinology, 2007 - Elsevier
      Feeding time is a major synchronizer of many physiological rhythms in many organisms. Alteration in the nutritional status, specifically fasting, also affects the secretion rhythms of growth hormone (GH) and insulin-like growth factor-I (IGF-I). In this study, we investigated whether the expression patterns for the mRNAs of GH, prolactin (PRL) and somatolactin (SL) in the pituitary gland, and insulin-like growth factor I and II (IGF-I and IGF-II) in the liver of juvenile rabbitfish (Siganus guttatus) follow a rhythm according to feeding time and whether these hormone rhythms changes with starvation. Hormone mRNA levels were determined by real time PCR. The daily expression pattern for the mRNAs of GH, PRL and SL was not altered whether food was given in the morning (10:00 h) or in the afternoon (15:00 h). The daily GH mRNA expression pattern, however, was affected when food was not available for 3 days. In contrast, the daily expression pattern for IGF-I mRNA reaches its peak at roughly 5–6 h after feeding. This pattern, however, was not observed with IGF-II mRNA. During 15-day starvation, GH mRNA levels in starved fish were significantly higher than the control fish starting on the 9th day of starvation until day 15. The levels returned to normal after re-feeding. In contrast to GH, PRL mRNA levels in starved fish were significantly lower than the control group starting on the 6th day of starvation until 3 days after re-feeding. SL mRNA levels were not significantly different between the control and starved group at anytime during the experiment. Both IGF-I and IGF-II mRNA levels in starved group were significantly higher than the control fish on the 3rd and 6th day of starvation. mRNA levels of both IGF-I and II in the starved fish decreased starting on the 9th day of starvation. While IGF-I mRNA levels in the starved group continued to decrease as starvation progressed, IGF-II mRNA levels were not significantly different from the control during the rest of the starvation period. The results indicate that aside from GH and IGF-I, PRL and IGF-II are likewise involved in starvation in rabbitfish.
    • Book chapter

      Nutritional diseases 

      EC Amar & CR Lavilla-Pitogo - In K Nagasawa & ER Cruz-Lacierda (Eds.), Diseases of cultured groupers, 2004 - Aquaculture Department, Southeast Asian Fisheries Development Center
      Nutritional diseases of fish may develop as a result of deficiency (undernutrition), excess (overnutrition), or imbalance (malnutrition) of nutrients present in their food. The disease usually develops gradually because animals have body reserves that make up for nutritional deficiency up to a certain extent. Disease signs develop only when supply of any diet component falls below critical level. When there is too much food, the excess that is converted to fat and deposited in fish tissues and organs, may severely affect physiological functions of the fish.
    • 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

      Partial replacement of soybean meal with fermented copra meal in milkfish (Chanos chanos, Forsskal) diet 

      MJS Apines-Amar, RM Coloso, CJ Jaspe, JM Salvilla, MNG Amar-Murillo & CA Saclauso - Aquaculture, Aquarium, Conservation and Legislation, 2015 - Bioflux
      Feeding trials were conducted to determine the optimum partial replacement level of soybean meal (SBM) with fermented copra meal (FCM). Isonitrogenous and isocaloric diets containing 0, 5, 10, 15, 20, and 25% of the locally produced FCM partially replacing SBM protein by 0, 12, 27, 41, 56, and 71%, respectively and fully replacing copra meal were formulated. The diets were fed to the fish with an initial weight of 2.83±0.14 g for 12 weeks. Thereafter, the best diet was further tested in a preliminary feeding trial in brackishwater grow-out ponds to verify the performance of the formulated diet against a commercial milkfish feed in an outdoor grow-out system. The results of the indoor tank feeding trial indicated that weight gain of the fish was significantly better in the group fed diet 2, with 5% dietary FCM but further increase in the FCM inclusion level up to 20% of the diet did not exhibit statistical differences against the control. Moreover in the preliminary pond feeding trial, growth and feed conversion ratio (FCR) of the fish fed the FCM diet were significantly higher than the commercial control diet. Survival and nutrient composition of the fish carcass were not adversely affected by the treatments. Hence, optimum dietary FCM inclusion level was determined at 5% of the milkfish diet replacing 100% copra meal and 12% SBM protein. However, in terms of economics, up to 20% FCM can be included in the diet replacing 56% SBM protein may be possible with growth comparable to the FCM-less control.
    • Article

      Reproductive performance of hatchery-bred donkey's ear abalone, Haliotis asinina, Linne, fed natural and artificial diets 

      MN Bautista-Teruel, OM Millamena & AC Fermin - Aquaculture Research, 2001 - Blackwell Publishing
      Hatchery-bred donkey's ear abalone, Haliotis asinina, Linne broodstock were given diets consisting of natural food, seaweed (SW), Gracilariopsis bailinae, D1; combination of SW and artificial diet (AD), D2; and AD alone, D3. Equal numbers of 1 : 1 female and male abalone were stocked in 24 units, 60 L tanks with eight replicate tanks per dietary treatment. Reproductive performance, e.g. number of spawnings, instantaneous fecundity and egg hatching rates, was monitored over 270 days. The mean number of spawnings was not significantly different among treatments. The mean instantaneous fecundity and percent hatching rates were significantly higher in abalone fed D2 or D3 compared to those given D1. Survival of abalone broodstock fed D1 was, however, significantly higher at 88% than those fed either D2 or D3 at 75%. Fatty acid analysis showed that the n-3/n-6 fatty acid ratios of abalone hepatopancreas reflected those of their diets. Mature abalone ovary had n-3/n-6 fatty acid ratio of 1.3. A higher amount of essential nutrients in the artificial diet such as protein, lipid and the highly unsaturated fatty acids, e.g. 20 : 4n-6, 20 : 5n-3, 22 : 6n-3 in abalone fed D2 or D3, may have influenced the increased reproductive performance.
    • magazineArticle

      Science and future of aquaculture 

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

      Ultrastructure of the anterior intestinal epithelia of the orange-spotted grouper Epinephelus coioides larvae under different feeding regimes 

      YH Primavera-Tirol, RM Coloso, GF Quinitio, R Ordonio-Aguilar & LV Laureta Jr. - Fish Physiology and Biochemistry, 2014 - Springer Verlag
      Enterocytes of the anterior to midsection of the intestine in grouper Epinephelus coioides larvae were compared among different treatments: unfed to the point-of-no-return (PNR), fed natural food only, and co-fed natural food and artificial diet. On day 3, the nutritional condition of unfed grouper larvae regressed with its reduced enterocyte heights which were further degraded on day 4, the PNR, when all the enterocytes were in advanced stages of apoptosis. The apoptosis appeared to be internally directed via the mitochondria. Among day 3 fed larvae, enterocyte heights of those fed artificial diet did not differ from those fed natural food only. Dietary phospholipid deficiency was indicated in larvae co-fed artificial diet on day 3 with an unusually large chylomicron opening into the inter-enterocyte space, and on days 6 and 33 by intestinal steatosis. On day 19, scant to absent lipid droplets in enterocytes of larvae disclosed heightened nutritional requirement preparatory to metamorphosis. As observed in unfed day 3 and premetamorphic day 19 E. coioides, larvae undergoing critical periods and starvation during development employ apoptosis to dispose of degenerated enterocytes that are phagocytosed by adjacent healthy enterocytes without causing inflammatory distress. Upon metamorphosis, grouper larval gut develops better immunity fitness with eosinophilic granule cells observed in the intestinal epithelia of day 33 larvae. Future studies on grouper larval nutrition may consider the appropriate dietary phospholipid levels and larval competence to biosynthesize highly unsaturated fatty acid from linoleic acid vis-à-vis the use of plant ingredients in artificial diet formulations. In vivo challenge tests may validate appropriate dietary nutrient supplementation and lead to better feed formulation, matching the varying energetic demands and digestive capacities of developing E. coioides larvae.
    • Article

      Use of copepod nauplii during early feeding stage of grouper Epinephelus coioides 

      JD Toledo, MS Golez, M Doi & A Ohno - Fisheries Science, 1999 - Japanese Society of Fisheries Science
      Newly-hatched Epinephelus coioides larvae were stocked in five 5-ton tanks at an initial density of 25, 000 ind/tank. Copepod nauplii were propagated in four of these tanks by inoculating various densities (20 to 80 ind/l) of mixed copepodids of Acartia tsuensis, Pseudodiaptomus spp., and Oithona sp. three days before stocking larvae. Rotifers were added in these tanks on Day 7 at an initial density of 5, 000 ind/l. Larvae in the remaining tank were fed rotifers (only) starting Day 2 at 5, 000 ind/l. The feeding incidence, gut content, growth, and survival of larvae were better in tanks with higher density of copepodids (60-80 ind/l). These indices were lowest in larvae given rotifers only. Total n-3 HUFA of copepods was 2 to 3 times higher than rotifers. High percentages of 22:6n-3 (DHA) were detected in the fatty acid composition of Pseudodiaptomus (13%) and Acartia (24%) with DHA/EPA (20:5n-3) values of 1.4 and 2.6, respectively. By providing nauplii of copepods at the early feeding stage, an average survival of 3.4% at harvest (Day 36) was obtained in a pilot scale grouper seed production trial in three 10-ton tanks.
    • Article

      Utilization of feed pea, Pisum sativum, meal as protein source in practical diets for juvenile shrimp, Penaeus monodon 

      MN Bautista-Teruel, PS Eusebio & TP Welsh - Aquaculture, 2003 - Elsevier
      The potential of feed pea meal as an alternative protein source to soybean meal in practical diets for the juvenile tiger shrimp, Penaeus monodon, was assessed in several experiments. Six isonitrogenous diets were formulated to contain 40% protein. Protein from the feed pea meal replaced 0%, 20%, 40%, 60%, 80%, and 100% of the protein from defatted soybean meal in the diets. These values were equivalent to 0%, 5%, 10%, 15%, 20%, 25%, respectively, of the total protein in the diet. A negative control with no protein sources was added to the treatments. Twelve shrimp post-larvae with an average weight of 0.02±0.01 g were randomly assigned in thirty-five 60-l oval tanks equipped with a flow-through seawater system. The shrimp were fed the formulated diets at a daily feeding rate of 20–25% body weight for 90 days in five replicate samples. No significant differences (P>0.05) were observed in weight gain, feed intake, feed conversion ratio (FCR) and protein efficiency ratio (PER) of shrimp fed diets 0 up to the highest level of replacement. Weight gain of shrimp fed the negative control was, however, significantly lower (P<0.05) compared to the rest of the treatments. Specific growth rates (SGR) of shrimp showed likewise no significant differences among treatments except for the negative control. Survival of shrimp for all treatments ranged between 75% and 100%. The apparent dry matter (ADMD) and protein (APD) digestibilities of the dry feed pea in P. monodon were high at 73.38±4.98 and 92.74±2.62, respectively. Digestibility coefficients for dry matter and protein for the feed pea meal-based diets increased with increasing level of feed pea replacement. There were no significant differences in whole body composition (dry matter, protein, lipid, ash, fiber) of shrimp fed the various diets with feed pea replacement. Pellet water stability was similar for all diets even up to the highest level of replacement. The results have demonstrated that feed pea meal has a very good potential as a substitute protein source up to 100% of the protein from defatted soybean meal, which is equivalent to 25% of the total protein in the diet. An inclusion level of up to 42% in the juvenile shrimp P. monodon practical diet did not manifest any adverse effects on growth, feed intake, FCR, survival, body composition, and digestibility coefficients for dry matter and protein of the shrimp.