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Broodstock Diets (broodstock + diet)
Selected AbstractsThe effect of vitamin A supplementation in broodstock feed on reproductive performance and larval quality in Penaeus chinensisAQUACULTURE NUTRITION, Issue 5 2004L. Mengqing Abstract The effect of feeding four semi-purified diets A1, A2, A3, A4, containing different vitamin A acetate levels 0, 20, 40, 60 mg kg,1 diet, respectively, on fecundity, egg hatching rate, larval survival rate and vitamin A content in eggs of Chinese shrimp (Penaeus chinensis) broodstock was compared with a fresh clam diet (control) in a 60-day feeding trial. The broodstock shrimp fed the diet with 60 mg kg,1 vitamin A acetate added exhibited significantly higher fecundity (P < 0.01). Hatching rate was highest with diet A4 (P < 0.05), whereas hatching rates were similar fed diets A1, A2, A3. Increasing levels of vitamin A in broodstock diet resulted in improvement in larval quality. The vitamin A levels in shrimp eggs from broodstock fed with diet A4 were higher compared with those from broodstock fed with diet A1, A2 (P < 0.01). The fecundity and hatching percentages were positively correlated with the vitamin A content in eggs in the present study. The results of this study showed that higher level of vitamin A in broodstock diet may have positive effects on fecundity and larval quality in P. chinensis. [source] Spontaneous Spawning of Captive Red Snapper, Lutjanus campechanus, and Dietary Lipid Effect on Reproductive PerformanceJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2008Nikolaos Papanikos Two experiments addressed the spontaneous spawning of red snapper, Lutjanus campechanus, under controlled temperatures and photoperiods and the effect of broodstock diets supplemented with oils rich in polyunsaturated fatty acids. In Experiment 1, broodfish were fed a standard diet (ST1) and one enriched with menhaden oil (ER1) over a 355-d period. ER1-influenced egg fatty acid profile, however, did not positively influence egg production. Both diets produced highly viable eggs and larvae but results varied within treatments. In Experiment 2, broodfish were fed either a standard diet (ST2) or one supplemented with oils (ER2) rich in docosahexaenoic and arachidonic acid using a 203-d cycle. Both treatments produced eggs but fertilization rates ranged 0,10%. There was no clear influence of the diets on egg fatty acid profiles. These results indicate that red snapper can spawn spontaneously in tanks under controlled environmental conditions and produce viable eggs and larvae when fed diets based on squid, shrimp, and fish. The fatty acid composition of the diets was reflected in the eggs to some degree, but the oil enrichments did not further enhance the reproductive performance and egg quality under the conditions of this study. [source] Effect of different diets on larval production, quality and fatty acid profile of the marine ornamental shrimp Lysmata amboinensis (de Man, 1888), using wild larvae as a standardAQUACULTURE NUTRITION, Issue 5 2009R. CALADO Abstract The present work evaluates the influence of broodstock diets [Marine Cuisine®, MC, MC supplemented with highly unsaturated fatty acid- (HUFA) enriched Artemia biomass , MC + AB, and MC supplemented with squid , MC + S] on larval production, newly hatched and early zoeal stage survival and fatty acid profile of newly hatched larvae of Lysmata amboinensis. These parameters are compared with those from larvae hatched from embryos spawned in the wild. The number (±SE) of larvae produced with MC and MC + S (1077 ± 219 and 1103 ± 184, respectively) was similar to that in broodstock carrying embryos spawned in the wild (1224 ± 111), while those fed MC + AB displayed significantly lower values (1044 ± 161). Larvae produced with MC + AB displayed lower survival for all starvation periods, while larvae spawned in the wild displayed the highest survival. No larvae resisted 144 h of starvation and none moulted to zoea II. The fatty acid comparison revealed that larvae from embryos spawned in the wild displayed the highest levels of DHA, as well as higher DHA/EPA and n -3/n -6 ratios. These results suggest that broodstock diets commonly used to promote ornamental shrimp's maturation (based on mixed frozen components) are far from being optimal. [source] Fatty acid nutritional quality of sea urchin Paracentrotus lividus (Lamarck 1816) eggs and endotrophic larvae: relevance for feeding of marine larval fishAQUACULTURE NUTRITION, Issue 4 2009J.M. GAGO Abstract Sea urchin eggs and larvae have been suggested as potential live prey for marine fish larval feeding. This study evaluated the fatty acid composition of Paracentrotus lividus eggs, prisms and four-armed plutei, obtained from wild and captive broodstocks fed on raw diets: maize, seaweed and a combination of maize and seaweed. Amounts of essential fatty acids (EFA) for marine fish larvae [arachidonic acid (ARA), eicosapentaenoic acid (EPA) and docosahexanoic acid (DHA)] were determined in eggs and endotrophic larvae. ARA ranged from 3.93% in eggs from combination to 18.7% in plutei from maize diets. In any developmental stage, EPA amounts were always lower than 5% for the raw diets, and DHA showed null or trace amounts including the wild diet. Thus, broodstock-prepared diets had to be formulated based on different lipid sources (Algamac, linseed oil, cod liver oil and olive oil) in order to test eggs and larvae EFA enhancement. EFA improvement was possible for all tested prepared diets. Algamac diet lead to superior EFA enhancement mainly in DHA (7.24%, 4.92% and 6.09% for eggs, prisms and plutei, respectively) followed by cod liver oil diet. Only these two lipid sources should be considered for prepared broodstock diets in order to obtain suitable live prey for fish larval feeding. [source] Experimental broodstock diets as partial fresh food substitutes in white shrimp Litopenaeus vannamei B.AQUACULTURE NUTRITION, Issue 4 2002R. WOUTERS In the first experiment, conducted in a research facility, Litopenaeus vannamei broodstock were fed either a 100% fresh food control treatment (FRE, consisting of frozen squid, oyster, mussel and enriched Artemia biomass in a 2.3:1.4:1.3:1 dry matter ratio) or one of the two treatments in which 50% [dry matter (DM)] of the fresh food was substituted with experimental artificial diets: a dry diet based on freeze-dried Artemia biomass (ART) and a control dry diet (CON). In the second experiment, conducted in a commercial hatchery, shrimp broodstock were fed either a fresh ration (FRE, consisting of frozen squid, polychaetes and enriched Artemia biomass in a 2.5:1.5:1 DM ratio) or the same experimental artificial diets (ART and CON) replacing 50% of the DM by elimination of polychaetes and Artemia biomass. In experiment 1 treatments CON and ART produced better results (P=0.05) than treatment FRE in terms of spawn performance and egg production per female. In experiment 2 no differences were detected among treatments FRE and CON whereas treatment ART performed better (P=0.05) in terms of spawning, egg production per female and spermatophore quality. Broodstock survival and offspring quality did not differ between treatments in either experiment. [source] Dietary effects of n-3 highly unsaturated fatty acid levels on egg and larval quality, and the fatty acid composition of the eggs of Chilean flounder Paralichthys adspersus broodstockAQUACULTURE RESEARCH, Issue 12 2009Rodolfo Wilson Abstract The effects of dietary n-3 highly unsaturated fatty acid (n-3 HUFA) on eggs and larval quality were investigated in the Chilean flounder Paralichthys adspersus. Broodstock were fed with three formulated diets with similar proximate compositions but different n-3 HUFA (2.1%, 3.1% or 4.1%) estimated levels from 5 months before and during the spawning period. The diet with an intermediate n-3 HUFA level resulted in a significantly higher (P<0.05) percentage of buoyant eggs (68.2 ± 2.9%), fertilization (92.8 ± 3.9%), normal cell cleavages (93.5 ± 1.9%), hatching rate (87.7 ± 4.1%) and normal larvae (76.3 ± 3.7%) compared with the other two diets. In contrast, high levels of n-3 HUFA produced larvae with a higher survival capacity when subjected to fasting. The diet with the lowest content of n-3 HUFA produces lower quality eggs and larvae. The n-3 HUFA level in eggs increased with an increase in the dietary level, and the n-3/n-6 ratios were 1:1, 2:1 and 3:1. The DHA/EPA and EPA/ARA ratios of 2 and 4 in eggs, respectively, were associated with improved egg and larval quality and were similar to the ratios found in eggs from wild broodstock. Attainment of optimal fatty acid contents in broodstock diets is one of the key factors for producing the high-quality spawning required for managed culture of this flounder. [source] |