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1.
The aim of this study was to evaluate the effects of Artemia nauplii enriched with different concentrations of highly unsaturated fatty acids (HUFAs) on the lipid metabolic response, peroxidation, and antioxidant defence status of the lined seahorse (Hippocampus erectus) juveniles. Twenty‐day‐old juveniles were fed Artemia nauplii enriched with four different concentrations (0.0 µL/L [control, A], 13.5 µL/L [B], 27.0 µL/L [C], and 54.0 µL/L [D]) of HUFAs (two thirds DHA and one third EPA) for 30 d. The activities of lipase and lipoproteinlipase of the juveniles significantly increased with increasing HUFA concentration; however, the activities of malate dehydrogenase and lactate content decreased with increasing HUFA concentration. Alkaline phosphatase activity and pyruvic acid content were not significantly different among the three treatments and the control. Malonaldehyde content was significantly negatively related to the enrichment concentrations (in Treatments A, B, and C); however, it increased significantly in Treatment D. The activities of superoxide dismutase in Treatments A and B were significantly higher than that in Treatments C and D. Catalase activity increased significantly from the control to Treatment C, then decreased significantly in Treatment D. Glutathione peroxidase activities increased significantly with increasing concentration of HUFAs, and peaked in Treatment D. The results indicate that dietary HUFAs are able to modify some enzymatic activities, and moderate dietary HUFA supplementation significantly promotes lipid metabolism and reduces lipid peroxidation products by enhancing antioxidant defence in the juveniles. However, excess HUFAs may result in adverse effects on the enzymatic activities in the juveniles, which might be related to oxidative stress.  相似文献   

2.
Three commercially available fatty acid enrichment emulsions (DC Selco, DC DHA Selco and DC Super Selco) were used to enrich Artemia nauplii fed to seahorse, Hippocampus sp. fry. The emulsions varied in their n-3 highly unsaturated fatty acid (HUFA) composition. Total n-3 HUFA content ranged from 200 to 450mgg-1 between the three emulsions while levels of eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) ranged between 47–220 and 80–190mgg-1, respectively. Survival and growth of seahorses at the end of the 30 day growth trial were greater in treatments receiving enriched Artemia. Seahorses receiving Artemia enriched with DC DHA Selco and DC Super Selco showed significantly (p < 0.05) greater mean survival (71.6 ± 6.0% and 78.3 ± 6.0%, respectively) than those receiving unenriched Artemia (48.3 ± 6.0%). Mean standard length was also significantly greater (p < 0.05) in fry fed DC DHA Selco and DC Super Selco enriched Artemia (20.2 ± 0.3 and 19.7 ± 0.3mm, respectively) compared to those fed unenriched Artemia (18.1 ± 0.3mm). The results show that dietary n-3 HUFA are essential for optimal growth and survival of Hippocampus sp. and, based on the fatty acid compositions of the enriched Artemia used in this study, indicate that the level of dietary DHA supporting optimal growth and survival is greater than 9.3mgDHAg-1 dry weight.  相似文献   

3.
用3种营养强化剂强化的轮虫和卤虫无节幼体投喂牙鲆仔鱼,研究牙鲆仔鱼的生长、成活、体脂肪酸的组成。结果表明:用强化的轮虫和卤虫无节幼体投喂牙鲆仔鱼,成活率、增重均显著高于对照组(p<0 01),其中V号强化剂的效果最好,成活率为29 34%,比对照组提高100%;增重倍数为217 90,比对照组提高68 61%;这是由于V号强化剂强化的卤虫无节幼体体内含有较多的AA的缘故,饵料中AA含量的提高,可以提高牙鲆仔鱼的成活率、促进其生长。牙鲆摄食强化过的轮虫、卤虫无节幼体后,其EPA、DHA、n-3HUFA、PUFA的含量随着饵料中含量的升高而升高,这也是牙鲆仔鱼生长速度和成活率提高的重要因素之一。  相似文献   

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6.
The palm ruff, Seriolella violacea (Cojinoba), is a potential new species for Chilean aquaculture. To approach Cojinoba larviculture, an experimental Artemia enrichment emulsion, containing docosahexaenoic acid (DHA)/eicosapentaenoic acid (EPA) = 2.5, supplemented with vitamin E, astaxanthin, and β‐glucan, was evaluated in both Artemia and Cojinoba larvae, 30–50 d.a.h. This study tested an experimental enrichment emulsion versus a commercial emulsion, with an integral approach of multicompound emulsions. After 23 h enrichment, experimental emulsion (EE)‐enriched nauplii reached DHA and EPA concentrations of 23.8 and 18.7 mg/g dry weight (dwt), respectively, while in Cojinoba larvae they were 18.4 and 19.7 mg/g dwt. Control emulsion (CE)‐enriched nauplii exhibited lower DHA and EPA (6.1 and 7.7 mg/g dwt), while only DHA decreased in the control larvae (12.6 mg/g dwt). Vitamin E was higher in EE‐enriched nauplii (29.2 mg/100 g dwt) than in the control (8.4 mg/100 g dwt). Larvae fed EE‐enriched Artemia exhibited 8% increase in survival and 19% in growth compared with the control. Astaxanthin was detected only in larvae fed EE‐enriched nauplii. The tumor necrosis factor‐α concentration was not significantly different between larvae fed EE‐ and CE‐enriched nauplii. EE looks promising as an Artemia enrichment and experimental diet to assess palm ruff larval requirements, and has a positive impact on fish larvae performance.  相似文献   

7.
Seahorses are ambush predators that swallow the prey through their tubular snout. In order to better understand mouth growth and its effect on prey preference by juveniles of the seahorse Hippocampus guttulatus, experimental assays were carried out by feeding juveniles (0–30 – d after male's pouch release [dar]) on a mixture of rotifers, Brachionus plicatilis; Artemia nauplii; and copepods; Acartia tonsa. Mouth development in juveniles was accomplished by growth of upper and lower jaws, which were linearly correlated with juvenile length, whereas mouth width (MW) and height (MH) grew exponentially with juvenile size. Additionally, MW and MH were exponentially correlated, so that the transversal section of the mouth increased linearly with juvenile age and length. Gut content and Ivlev' selectivity index demonstrated a permanent rejection of rotifers for the whole experimental period and a clear preference of juveniles for copepods from 0 to 15 dar and for Artemia nauplii afterwards. Results also suggest that juveniles are able to ingest larger prey than those provided as the limiting factor in prey ingestion was not MW, as for many marine fish larvae, but mouth area. A tentative feeding schedule to successfully feed H. guttulatus juveniles from 0 to 30 dar is proposed.  相似文献   

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9.
The present study examines the effect of four semi‐purified diets (casein–gelatin based) where the source of fatty acids was free (esterified) oleic acid and linoleic acid (LA) (LOA diet), linseed and olive oil (predominantly LA and linolenic acid) (LO diet), cod liver oil (rich in highly unsaturated fatty acids) (CLO diet), and soybean lecithin (phospholipids; mostly LA) (LE diet) on the growth of juvenile South American catfish (surubim, Pseudoplatystoma fasciatum, Pimelodidae) (0.98 ± 0.04 g individual weight). Fish were fed at a restricted–readjusted feeding rate for 8 wk. At the end of the experiment, LE‐diet‐fed fish grew significantly larger than those of the other three groups (P < 0.05). Considerable cannibalism was observed in all the treatments. It is suggested that the quantitative growth performance may possibly change under other conditions, with less or no cannibalism. Survival did not differ significantly among the fish fed four different diets. Muscle and liver lipid contents did not vary among dietary treatments (P > 0.05), but whole‐body lipid concentrations were affected by dietary treatments. Fish fed LE diet contained significantly lower lipid level than those fed three other diets (P < 0.05). Muscle and liver fatty acid profiles reflected dietary fatty acid composition. Arachidonic acid level was significantly higher in muscle and liver of fish fed LOA and LE diets than in those fed LO and CLO diets. The results suggest that the efficiency of elongation and desaturation of 18C fatty acids depends on the dietary lipid source, and South American catfish has considerable capacity to transform linoleate to arachidonate.  相似文献   

10.
Further development of high‐quality feeds for hatchery‐reared haddock in the North Atlantic would benefit from a standard formulation that can be used as a reference for hatcheries and laboratory studies. A practical microparticulate diet (PMD) developed and evaluated with newly metamorphosed juvenile haddock, Melanogrammus aeglefinus L., postlarvae is proposed. Survival of fish fed PMD was just as high (88–89%; P > 0.05) as those fed a high‐quality imported feed (Biokyowa). Alternatively, fish fed PMD had higher (P < 0.05) final fork lengths (39.5 vs. 35.1 mm), wet weights (851.3 vs. 580.2 mg) and weight gains (1637.2 vs. 1115.7%). No differences (P > 0.05) in whole‐body moisture (846–857 g/kg), ash (17–18 g/kg), or protein (101 g/kg) contents were found. Lipid content of fish fed PMD (26 g/kg) was higher (P < 0.05) than those fed Biokyowa (21 g/kg) despite PMD containing 15 g/kg lower dietary lipid, suggesting higher intake and/or lipid retention. The PMD formulation proved to be a highly suitable weaning diet for haddock postlarvae based on high feed acceptance, survival, and fish growth. Given the economic and logistical difficulties associated with importing commercial weaning feeds, this easily produced practical weaning diet has good potential for use by laboratory researchers and farm managers for hatchery‐based nutrition research with haddock postlarvae.  相似文献   

11.
Anesthetic disposal for fish often results in physiological and behavioral responses. There is limited information involved on the metabolic and behavioral responses of the seahorses. The lined seahorse, Hippocampus erectus, is of great interest in the sciences because of its unusual S‐shaped morphology and male pregnancy behavior. This study found that the lined seahorse could be effectively anesthetized into Stage II at the concentrations of 10 mg/L clove oil or 20 mg/L MS‐222 based on the comparison of six different treatments. The ventilation frequency, oxygen consumption, and ammonia‐N excretion of the seahorses were decreased significantly as soon as they were exposed to the anesthetic agents. A higher O : N ratio was found in seahorses anesthetized by clove oil as compared to those exposed to MS‐222. After the anesthetic treatment, the feeding frequencies of recovered seahorses were low at the beginning and then increased during the 7‐d culture. Moreover, there was no incremental difference of wet weights among the tested seahorses (P = 0.534). The findings indicate that the anesthetic process has few effects on the feeding and short‐term growth of seahorses in spite of the occurrence of physiological and behavioral responses.  相似文献   

12.
Red claw crayfish Cherux quadricarinatus is one of more than a hundred species of Australian freshwater crayfish. However, because of its rapid growth rate, communal and non‐burrowing behavior, ease of spawning, wide temperature and dissolved oxygen tolerance, and no free‐swimming larval stages, red claw may be the best candidate among the Australian crayfishes for semi‐intensive or intensive aquaculture in the United States. The objective of the study was to examine the effects of growth, survival, and fatty acid composition of newly‐hatched red claw when fed four practical diets with or without lecithin and cholesterol. However, little is known of its nutritional requirements or practical diet formulations. An 8‐wk feeding trial was conducted in a recirculating system with newly‐hatched juvenile (mean individual weight, 0.2 g) red claw, each stocked in separate plastic mesh culture units containing their own individual water line. Water was recirculated through biological and mechanical filters. Practical diets were formulated to be isonitrogenous (40% protein) and isocaloric (4 kcal available enerpy/g of diet) and contained menhaden fish meal (25%), soybean meal (35%, except in Diet 4), and shrimp meal (10%, except in Diet 4) as protein sources. Diet 1 had 0.5% lecithin added and 1.0% cholesterol added: Diet 2 contained 0% lecithin and 1.0% cholesterol; Diet 3 contained 0.5% lecithin and 0% cholesterol: and Diet 4 contained 0% lecithin and 0% cholesterol. After 8 wk, juvenile red claw fed diets with 0% supplemental lecithin (Diets 2 and 4) had no significant difference (P >0.05) in final weight and percentage weight gain (5.6 g and 2626%. respectively) compared to red claw fed the control diet (Diet 1) containing 0.5% lecithin. Red claw fed a diet without added cholesterol (Diet 3) had significantly (P 0.05) lower final weight (3.6 g) and percentage weight gain (1,717%) compared to red claw fed the control diet (Diet 1). However, red claw fed Diet 4 (containing 0% added cholesterol and 0% added lecithin) showed no significant (P >0.05) difference in final weight (5.1 g) and percentage weight gain (2254%) compared to red claw fed all other diets. There was no significant difference (P >0.05) among all diets for specific growth rate (SGR) which averaged 5.38%/d. Percentage survival was not significantly different among all treatments and was 76% for red claw fed Diet 1, 64% (Diet 2), 56% (Diet 3), and 80% (Diet 4). These results indicate that red claw fed Diet 4 containing 25% menhaden fish meal, 44.5% soybean meal, 0.5% choline chloride, 2% cod liver oil and 1% corn oil may satisfy the lecithin and cholesterol requirements and that the addition of dietary lecithin and cholesterol may not be necessary for good growth and survival of small (0.2 g) juvenile red claw. This may allow for less expensive diet formulations for use by producers of red claw crayfish.  相似文献   

13.
This investigation examined the intestinal microbial flora among healthy and intestinal‐diseased seahorses Hippocampus trimaculatus, Hippocampus erectus, and Hippocampus spinosissimus by utilizing polymerase chain reaction‐denaturing gradient gel electrophoresis (DGGE) and densitometric analysis. Results demonstrated that 16 disparate DGGE bands belong to six major bacterial groups, which were Vibrionace, Enterobacteriacea, Rhodobacteraceae, Sphingomonadaceae, Flavobacteriaceae, and Alcaligenaceae. It was found that Vibrionaceae was the dominant population among the healthy and intestinal‐diseased seahorses. Vibrio ponticus strain XJ3 and Vibrio neptunius strain WT82, especially V. ponticus strain XJ3 of high abundance, were identified for the first time in seahorses and concluded to be intestinal disease pathogens because of their co‐existence in three intestinal‐diseased seahorse species and other reported fish or oyster. In comparison, uncultured bacterium clone Alcaligenaceae, Vibrio sp., uncultured bacterium clone Rhodobacteraceae, Serratia nematodiphila strain, and Serratia marcescens strain comprised the basic intestinal bacterial flora of all healthy seahorses. This study is the first to report the presence of S. nematodiphila in seahorses.  相似文献   

14.
Growth and survival rates of smallmouth bass ( Micropterus dolomieui ) were compared for fishes reared from larval stages, for three weeks using different feeding regimes. Diets consisted of a commercial dry diet formulated for larval fishes, the dry diet plus Artemia salina nauplii, and Artemia salina nauplii alone. Smallmouth bass on the three diets showed average daily gains of 0.7, 0.7 and 0.5 mm/day and 11.0, 11.4 and 5.2 mg/day, respectively. Condition factors for the three diets were not significantly different ( P > 0.05). Mean survival rates were 39, 85 and 77% respectively.  相似文献   

15.
As algae and their concentrations are important factors for mass culture of rotifer, two experiments were conducted to find the effects of two types of algae, Chlorella sp. and Scenedesmus obliquus, and three concentration of chosen algae (0.1 × 106, 1 × 106, and 10 × 106 cells/mL) on growth and fatty acid composition of freshwater rotifer, Brachionus calyciflorus. The result of the first experiment showed that the maximum density of rotifer was significantly higher when fed with Chlorella sp. (478 individuals/mL) than fed with S. obliquus (328 individuals/mL). Mean population growth rate (r) was 0.61 and 0.44 for rotifer fed with Chlorella sp. and S. obliquus, respectively. The amount of highly unsaturated fatty acid (HUFA) in rotifer fed with Chlorella sp. (3.32%) was relatively more than those fed with S. obliquus (2.65%). Then, Chlorella sp. was selected based on better performance. In the second experiment, the maximum rotifer density of 108 ± 8, 489 ± 47, and 493 ± 51 individuals/mL was reached after 5 d for the respective Chlorella sp. concentrations; at concentration of 10 × 106 cells/mL, the maximum density of 1820 ± 47 individuals/mL was obtained. Mean growth rate at mentioned concentrations was 0.18, 0.42, and 0.51/d, respectively. Increase in algal concentration was associated with a relative increase in HUFA and decrease in monounsaturated fatty acid.  相似文献   

16.
Under production conditions freshwater prawns Macrobrachium rosenbergii are supplied nutrients by a combination of prepared diets and natural pond organisms. For maximum production efficiency and profitability it is important that the nutritional contributions of natural foods be identified and quantified. In this study the relative importance of forage organisms previously identified as important natural foods for prawns in ponds were evaluated under controlled conditions. Juvenile prawns (average weight 1.80 ± 0.06 g) were stocked into 18 37.5-L aquaria at a density of 10 prawns per tank. The six dietary treatments tested were: 1) unfed (negative control); 2) commercially prepared diet (positive control); 3) oligo-chaetes; 4) chironomids; 5) zooplankton; and 6) a combination of the latter three. Each treatment was evaluated in triplicate aquaria for 7 wk. The growth rate of prawns in the unfed treatment was statistically lower than in fed treatments ( P < 0.05). There were no significant differences ( P > 0.05) between growth rates and survivals among prawns in the five fed treatments. Selective retention of arachidonic acid (20:4n-6), eicosapentanoic acid (22: 5n-3), and docosahexanenoic acid (22:6n-3) in unfed prawns likely indicates the relative nutritional importance of these fatty acids. Comparisons of whole-body fatty acid and amino acid concentrations of prawns and food organisms indicate that zooplankton and oligochaetes may have the most appropriate biochemical compositions as prawn food sources.  相似文献   

17.
以18日龄的牙鲆(Paralichthys olivaceus)稚鱼为研究对象,通过11 d 的生长实验,研究了添加不同比例的微藻粉替代鱼油对牙鲆稚鱼生长、存活率和脂肪酸组成的影响。以鱼油组(FO)为对照组,以裂壶藻粉(Schizochytrium sp.)、微绿球藻粉(Nannochloropsis sp.)和橄榄油替代不同比例的鱼油,配制成5组等氮等能的实验饲料,分别命名为鱼油组(FO),50%混合替代组(M50)、100%混合替代组(M100)、100%裂壶藻橄榄油替代组(S100)、100%微绿球藻橄榄油替代组(N100)。结果显示,微藻粉替代鱼油对牙鲆稚鱼的生长无显著影响;含有裂壶藻的各饲料组(M50、M100、S100)成活率显著高于 FO 组和 N100组(P?0.05);微藻粉替代鱼油不影响牙鲆稚鱼主要脂肪酸的组成;Person相关性分析发现,C14:0、C16:1n-7、C18:2n-6、C20:0、C18:3n-3、C22:0、C20:4n-3、EPA、C22:5n-6和 DHA 的百分含量均与其饲料中的百分含量呈显著正相关(P<0.05);总饱和脂肪酸、总单不饱和脂肪酸、n-3多不饱和脂肪酸的百分含量以及 DHA/EPA 比率均与其饲料组成表现出显著正相关(P<0.05)。综上所述,微藻作为脂肪源替代鱼油完全可以满足牙鲆稚鱼的生长和发育,各种脂肪酸均可以被牙鲆稚鱼充分消化和吸收,并且添加两种微藻后提高了稚鱼的 DHA 含量和 DHA/EPA 比率,与鱼油对照组相比显著提高了牙鲆稚鱼的成活率。因此,以微藻替代鱼油在牙鲆稚鱼的培育中是可行的。  相似文献   

18.
Dried Tetraselmis suecica was evaluated as a fish protein substitute when incorporated to replace (protein basis) 10% (TETRA10) and 20% (TETRA20) of the control diet. The diets were offered to nine groups of European sea bass (72 g) over 63 days. Test diets did not affect zootechnical performances nor carcass or fillet yields and proximate analysis of edible portion. Feeding TETRA20 resulted in lower apparent digestibility coefficients of protein, lipid, and organic matter, and hepatosomatic index compared to the control diet. T. suecica was able to replace up to 20% of fish protein without hampering growth performance and major quality traits of sea bass.  相似文献   

19.
本实验旨在研究饲料中豆油替代鱼油对圆斑星鲽(Verasper variegatus)幼鱼生长和肌肉脂肪酸组成的影响。用豆油分别替代0、25%、50%和75%的鱼油,配制4组等氮、等脂肪的饲料。选择初始体重为(65.47±1.57)g的圆斑星鲽幼鱼360尾,随机分为4组,每组3个重复,每个重复30尾鱼,养殖56 d。结果显示,(1)随着豆油替代水平的升高,增重率(WGR)呈现降低的趋势(P0.05),饲料系数(FCR)呈现升高的趋势(P0.05),25%替代组的WGR高于鱼油组(P0.05)。(2)豆油替代鱼油对圆斑星鲽肌肉的粗蛋白、粗脂肪、灰分和水分含量无显著性影响(P0.05),对肝体比(HSI)、脏体比(VSI)和肥满度(CF)无显著性影响(P0.05),豆油替代组肝脏的脂肪含量显著高于鱼油组(P0.05)。(3)随着饲料中豆油水平的增加,圆斑星鲽幼鱼肌肉亚油酸(C18:2n-6)和亚麻酸(C18:3n-3)显著升高(P0.05),而二十碳五烯酸(EPA)和二十二碳六烯酸(DHA)则显著降低(P0.05)。研究结果表明,在该实验条件下,饲料中高比例的豆油替代鱼油会降低鱼体的生长性能和肌肉脂肪酸营养品质。  相似文献   

20.
A feeding trial was conducted to determine the interactive effects of vitamin C (ascorbic acid, AsA) and E (α‐tocopherol, α‐Toc) supplementation with dietary oxidized fish oil (OFO) on the growth performance, whole‐body AsA, and α‐Toc concentrations and fatty acid composition of juvenile sea cucumber. In a 9‐wk feeding trial, juveniles (average weight: 0.6 ± 0.1 g) were cultured in twenty‐four 50‐L tanks (30 juveniles per tank) in triplicate, and fed with eight test diets containing two levels of OFO (8.9 and 156.9 meq/kg) with varying levels of vitamin C (500 and 1000 mg AsA equivalents/kg diet) and E (100 and 200 mg α‐Toc equivalents/kg diet) supplementation, respectively. Body weight gain of sea cucumber was significantly reduced by dietary OFO, while mortality and whole‐body thiobarbituric acid‐reactive substances value were increased significantly. Increasing dietary vitamin C and E levels significantly increased whole‐body α‐Toc and AsA concentrations, respectively. A high level of vitamin E combined with OFO led to consumption of AsA. Even with supplementation of a large dose of vitamin C and/or E in diets, growth performance could not be improved, probably due to the high levels of vitamins in the control diets.  相似文献   

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