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1.
真鲷仔稚鱼对实验微粒饲料中卵磷脂适宜需要量的研究   总被引:1,自引:0,他引:1  
制备了4种n-3HUFA含量基本相等、卵磷脂含量分别为0、2.5%、5.0%、7.5%的实验微粒饲料,探讨了卵磷脂的含量对真鲷仔稚鱼生长、存活、体内相关成分以及对外部压力的耐受性的影响。25d的养殖试验结果表明,当真鲷仔稚鱼的实验微粒饲料中卵磷脂含量不超过5.0%时,随着实验微粒饲料中卵磷脂含量的增加,真鲷仔稚鱼的生长速度和成活率也相应增加。养殖试验结束后,对仔稚鱼体内相关成分的分析结果表明,仔稚鱼体内n-3HUFA和DHA的含量随着实验微粒饲料中卵磷脂含量的增加而增加。但当卵磷脂含量从5.0%增加到7.5%时,真鲷仔稚鱼的生长速度、成活率以及体内n-3HUFA和DHA的含量却没有相应增加,因此,真鲷仔稚鱼对实验微粒饲料中卵磷腊的适宜需要量应为5.0%左右。活力测试结果表明,当真鲷仔稚鱼的实验微粒饲料中卵磷脂的含量不超过5.0%时,随着实验微粒饲料中卵磷脂含量的增加,真鲷仔稚鱼对外部压力的耐受性增强,但是当实验微粒饲料中卵磷脂的含量从5.0%增加到7.5%时,真鲷仔稚鱼对外部压力的耐受性并没有继续增强,从而进一步说明真鲷仔稚鱼对实验微粒饲料中卵磷脂的适宜需要量应为5.0%左右。  相似文献   

2.
制备3种基本组成相同、添加不同类型鱼油的微粒饲料。将3种微粒饲料分别投喂真鲷(Pagrus major)仔鱼,探讨了微粒饲料中鱼油n—3HUFA的不同分子结构对真鲷仔、稚鱼生长、存活的影响。25d的养殖试验结果表明,虽然饲料2中n-3HUFA的含量高于饲料1中n—3HUFA的含量,饲料3中n—3HUFA的含量同饲料1中n—3HUFA的含量相等,但是用饲料1投喂的真鲷仔、稚鱼的全长、成活率要优于分别用饲料2和饲料3投喂的真鲷仔、稚鱼的全长、成活率。而且,用饲料1投喂的真鲷仔、稚鱼体内n-3HUFA和DHA的含量高于用饲料2和饲料3投喂的真鲷仔、稚鱼体内n—3HUFA和DHA的含量,这说明真鲷仔、稚鱼对天然鱼油的消化、吸收要优于对乙酯化鱼油的消化、吸收。  相似文献   

3.
丁仔稚幼鱼期的摄食与生长   总被引:1,自引:0,他引:1  
丁鱼岁仔、稚、幼鱼期具有明显的昼夜摄食节律,其中,仔、稚鱼最大饱食率出现在16∶00到20∶00,00∶00到04∶00时有停食现象。幼鱼最大饱食率出现在14∶00到22∶00,昼夜无明显的停食现象。仔鱼食谱中主要是轮虫,稚鱼食谱渐丰富,幼鱼期食谱更为扩大,且出现了一定量的底栖动物。仔、稚鱼体重、全长瞬时增长率要高于幼鱼期,而且,体重快速增长期要先于全长快速生长期。仔、稚和幼鱼阶段是匀速生长。  相似文献   

4.
丁(鱼岁)仔稚幼鱼期的摄食与生长   总被引:3,自引:0,他引:3  
丁Gui仔、稚、幼鱼期具有明显的昼夜摄食节律,其中,仔、稚鱼最大饱食率出现在16:00到20:00,00:00到04:00时有停食现象。幼鱼最大饱食率出现在14:00到22:00,昼夜无明显的停食现象。仔鱼食谱中主要是轮虫,稚鱼食谱渐丰富,幼鱼期食谱更为扩大,且出现了一定量的底栖动物。仔、稚鱼体重、全长瞬时增长率要高于幼鱼期,而且,体重快速增长期要先于全长快速生长期。仔、稚和幼鱼阶段是匀速生长。  相似文献   

5.
海水仔稚鱼早期阶段氨基酸的营养生理研究进展   总被引:6,自引:0,他引:6  
深海海鱼鱼卵中的游离氨基酸占鱼卵总氨基酸含量的近50%(干重),游离氨基酸库中的游离氨基酸似乎是卵黄蛋白的水解产物。仔鱼吸收卵黄内源营养的过程中,游离氨基酸库中的游离氨基酸逐渐减少,到仔鱼开始摄食时,库中的游离氨基酸已近枯竭,游离氨基酸不仅是代谢能源,而且是体蛋白合成的基本原料,仔鱼开始摄食后,氨基酸作为分解代谢的重要物质,可能有高达60%的能量由氨基酸提供,由于仔稚鱼的生长主要是通过合成蛋白质增加鱼体的重量,加之仔稚鱼的生长速度很高,因此,仔稚鱼需要其饲料中有较高的氨基酸含量。仔鱼开始摄食后,其消化系统对蛋白质的水解和吸收能力较弱,海水仔稚鱼的早期阶段,仔鱼的肠道对游离氨基酸的吸收要高于对多肽和蛋白质中氨基酸的吸收,仔鱼开始摄食后,由浮游生物获得大量的游离氨基酸,用微粒饲料培育仔稚鱼,微脂粒技术可能是向饲料中添加游离氨基酸的实用技术。  相似文献   

6.
<正>饵料磷脂对仔稚鱼的生长发育产生很大的影响:磷脂是细胞膜的重要组成成分,能够提高脂肪的吸收和转运,提高饵料的质量,尤其是适口性并且还能为鱼类提供一些必需的营养素,如胆碱和肌醇[1]。然而不同种类的磷脂对鱼类的影响不尽相同,在考虑其对仔稚鱼的影响时必须考虑磷脂的种类和脂肪酸组成。在研究饵料磷脂对仔稚鱼的影响时非常难区分到底是完整磷脂的作用还是其所含的不同的脂肪酸的作用。本文旨在讨论磷  相似文献   

7.
用精制饲料添加一定量的磷脂和多不饱和脂肪酸,饲喂中华绒螯蟹大眼幼体并育成Ⅲ期仔蟹。结果表明:饲料中添加一定量的磷脂对提高大眼幼体育成仔蟹的成活率有较显著的作用,而添加多不饱和脂肪酸对提高大眼幼体到Ⅲ期仔蟹的成活率的作用不显著,但可显著地提高大眼幼体到I期仔蟹的成活率。另外,饲料中的不饱和脂肪酸含量可显著地影响仔蟹体内脂肪酸的百分含量。  相似文献   

8.
用精制饲料添加一定量的磷脂和多不饱和脂肪酸,饲喂中华绒螯蟹大眼幼体并育成Ⅲ期仔蟹。结果表明:饲料中添加一定量的磷脂对提高大眼幼体育成仔蟹的成活率有较显著的作用,而添加多不饱和脂肪酸对提高大眼幼体到Ⅲ期仔蟹的成活率的作用不显著,但可显著地提高大眼幼体到Ⅰ期仔蟹的成活率。另外,饲料中的不饱和脂肪酸含量可显著影响仔蟹体内脂肪酸的百分含量。  相似文献   

9.
日本主农饲料部最近出售一种新的仔稚鱼用配合饲料,这种饲料是在原来鲑鳟类、鲤鱼及多种海水鱼稚鱼所用的饲料基础上进行改良制成的。新饲料除继续保持原饲料具有的特性①主原料采用变热性少的鱼粉;②用强化必须脂肪酸和强化磷脂  相似文献   

10.
水产养殖     
040325投喂磷脂胆碱提高尼罗罗非鱼幼鱼 生长=Gr〔)wth improved in Juvenile Nile tilapia fed phosphatidyleholine仁刊,英〕/ Kasper CS,Brown PB// North.灿飞er.J. Aq,,ae.一2003,65(l)一39一43 为测定饲料中的磷脂胆碱对尼罗罗非鱼 幼鱼生长的影响进行了投饵试验。试验用尼 罗罗非鱼平均个体重12.49,基本饲料以酪 阮为蛋白源,含凝胶10.1%,含晶体L一氨 基酸21.9%。饲料蛋白质含量为犯%,饲 料中的硫氨酸总浓度为0.5%,蛋氨酸与胧 氨酸之比为94二6,胆碱浓度0.3%,亚油酸 浓度1 .1%一3.3%。7种含量的磷脂胆碱加 人基本饲料中,添加量分…  相似文献   

11.
The aim of the present study was to compare effects of dietary n-3 highly unsaturated fatty acids (HUFA) being incorporated in the phospholipid (PL) or in the neutral lipid (NL) fraction of the larval feed, on larval growth and histology of digestive organs in Atlantic cod ( Gadus morhua L.) larvae. Three isoproteic and isolipidic diets, labelled according to the percentage of n-3 docosahexaenoic acid and eicosapentaenoic acid contained in NL1 or in PL1 and PL3 of the diets, were fed to cod larvae from 17 days post hatching (dph) to 45 dph.
In the liver, hepatocytes and their nuclei were smaller in NL1 larvae compared with the PL larvae; the mitochondrial membrane structures were less dense and the amount of lipids observed in the liver was significantly higher in NL1 larvae compared with the PL3 larvae. The liver and gut size was related to larval size, with no differences between the larval groups. The results demonstrated that the essential fatty acids were more beneficial for cod larvae when they were incorporated in the dietary polar PL rather than in the NL, and that the n-3 HUFA requirements in cod larvae is possibly higher than that in the PL1 diet.  相似文献   

12.
The aim of this study was to evaluate the effects of dietary phospholipids (PL) sources (fish gonad G‐PL and soybean lecithin S‐PL) and levels (50 and 90 g kg?1 dry matter) on the performances and fatty acid (FA) composition of pikeperch larvae. From day 10 to day 34 posthatching (p.h.), larvae were fed with three isoproteic and isolipidic microdiets. The best results of growth and skeletal development were related to a high phospholipid level regardless of their origin and FA profile. Jaw deformities seemed associated with high dietary highly unsaturated FA (HUFA) level. The optimal level of eicosapentaenoic acid and docosahexaenoic acid (EPA + DHA) for pikeperch larvae appeared to be around 12 g kg?1 (dry matter) associated with a PL level around 90 g kg?1. FA composition of diets and larvae revealed a better incorporation of arachidonic acid, EPA and DHA into PL fraction especially in larvae fed with soybean PL. Moreover, 34‐day‐old pikeperch larvae may have capability of converting 18 carbon n‐3 FA into the n‐3 HUFA. Hence, for pikeperch larvae, PL from plant origin were as efficient as those from marine fish origin.  相似文献   

13.
This study was conducted to examine the effects of dietary ascorbic acid (AsA) and phospholipid (PL) and their interaction on growth, survival, and stress resistance in red sea bream larvae. Twenty‐six days old red sea bream were fed nine micro‐bound diets supplemented three levels of AsA (0, 800 and 1600 mg kg?1 diet) and PL (0, 20 and 40 g kg?1 diet) for 15 days. Dietary AsA and PL were both significant factors on survival rates. There was also an interaction between dietary AsA and PL on survival rate (P < 0.05). The larvae fed 800 or 1600 mg kg?1 AsA with 40 g kg?1 PL diets showed the highest survival rate, with values similar to those of the live‐food supplemented group. Stress resistance against low salinity exposure significantly increased with increased dietary level of AsA and PL. However, significant interaction of AsA and PL was not detected. The larvae fed 1600 mg kg?1 AsA with 40 g kg?1 PL diet showed the highest stress resistance among all diets, but it was not significantly different than that of larvae fed 800 mg kg?1 AsA with 40 g kg?1 PL diet. This study clearly demonstrated that combined use of AsA and PL can improve survival of 26–40 days posthatching red sea bream larvae. Moreover, the present study suggested that 800 mg kg?1 AsA with 40 g kg?1 PL in diet was needed for producing high quality seedling under the stressful conditions.  相似文献   

14.
The aim of the study was to determine the influence of dietary phospholipid (PL) levels on survival and development of first feeding gilthead sea bream (Sparus aurata) larvae. Larvae were fed from day 4 to 23 posthatching with an isoproteic and isolipidic formulated diet with graded levels of PL from 90–150 g kg?1 dry matter (DM). A dietary PL content of more than 90 g kg?1 DM seems to be necessary for sustaining growth of first feeding sea bream larvae. The survival rates of larvae fed the formulated diets (31–40% at day 23) were similar to those generally observed in marine aquaculture hatcheries with live prey feeding sequence. However, this high survival rate was not associated with high growth and the larvae showed, at the end of the study, a high proportion of individuals with abnormal liver and calculi in the urinary bladder. It is concluded that although the diets used here cannot be used in total replacement of live preys, they constitute a solid starting point for further nutritional studies with first feeding gilthead sea bream larvae.  相似文献   

15.
Although dietary marine phospholipids are able to improve culture performance of marine fish larvae in a further extend than soybean lecithin, both types of phospholipids (PL) markedly increase oxidative risk. The inclusion of a fat‐soluble antioxidant such as the vitamin E α‐tocopherol could allow a better control of oxidative stress. The objective of this study was to determine the combined effect of graded levels of α‐tocopherol with different levels and sources of krill phospholipids (KPL) and soybean lecithin (SBL) on growth, survival, resistance to stress, oxidative status, bone metabolism‐related genes expression and biochemical composition of sea bream larvae. Sea bream larvae were completely weaned at 16 dph and fed for 30 days seven microdiets with three different levels of PL (0, 40 and 80 g kg?1 diet) and two of α‐tocopherol 1500 and 3000 mg kg?1 diet. Sea bream larvae fed diets without PL supplementation showed the lowest survival, growth and stress resistance, whereas increase in PL, particularly KPL, markedly promoted larval survival and growth. However, feeding SBL markedly increased TBARs and GPX gene expression increasing the peroxidation risk in the larvae. Besides, KPL inclusion improved incorporation of n‐3 HUFA and, particularly, EPA into larval tissues, these fatty acids being positively correlated with the expression of BMP‐4, RUNX 2, ALP, OC and OP genes and to bone mineralization for a given larval size class. The increase in dietary α‐tocopherol tends to improve growth in relation to the n‐3 HUFA levels in the diet, denoting the protective role of this vitamin against oxidation. Indeed, dietary α‐tocopherol decreased the oxidative stress in the larvae as denoted by the reduction in larval TBARs contents and gene expression of SOD and CAT, but not GPX. Thus, increase in dietary α‐tocopherol effectively prevented the formation of free radicals from HUFA, particularly EPA, but did not affect the incidence of bone anomalies or the expression of genes related to osteogenetic processes.  相似文献   

16.
The objective of the present study was to compare the effectiveness of dietary marine phospholipids (MPL) obtained from krill and soybean lecithin (SBL) on the rearing performance and development of seabream (Sparus aurata) larvae. Larvae were fed from 16 to 44 day posthatching (dph) five formulated microdiets with three different levels (50, 70 and 90 g kg–1) of phospholipids (PL) obtained either from an MPL or from a SBL source. Larvae‐fed MPL show a higher survival, stress resistance and growth than those‐fed SBL, regardless the dietary PL level. Overall, the increase in MPL up to 70 g kg–1 total PL in diet was enough to improve larval gilthead seabream performance, whereas even the highest SBL inclusion level (90 g kg–1 PL) was not able to provide a similar success in larval growth or survival. Inclusion of SBL markedly increased the peroxidation risk as denoted by the higher TBARs in larvae, as well as a higher expression of CAT, GPX and SOD genes. Moreover, SBL tends to produce larvae with a lower number of mineralized vertebrae and a lower expression of osteocalcin, osteopontin and BMP4 genes. Finally, increasing dietary MPL or SBL lead to a better assimilation of polyunsaturated fatty acids in the larvae, n‐3HUFA (especially 20:5n‐3) or n‐6 fatty acids (especially 18:2n‐6), respectively. In conclusion, MPL had a higher effectiveness in promoting survival, growth and skeletal mineralization of gilthead seabream larvae in comparison with SBL.  相似文献   

17.
Effects of two weaning diets that differed in phospholipid (PL) classes on growth, survival and deformities of cod larvae and early juveniles were evaluated. Cod larvae were fed rotifers until 21 days post hatch (dph) and then weaning onto dry diet started. One group of larvae were fed a control diet with low levels of phosphatidylcholine (PC), PE and phosphatidylinositol (PI) and the other group of larvae were fed with an experimental diet containing higher levels of PC, PE and PI. Larvae fed with the control diet were significantly smaller than larvae fed with the experimental diet at the end of the experiment. Swim bladder abnormalities were significantly higher in larvae fed with control diet at 35 dph than the larvae fed with experimental diet; however, no significant difference was evident at 42 dph. Vertebral deformities were significantly higher in larvae fed with control diet and scoliosis was significantly different between the treatments. Survival was also significantly higher in the experimental group. Our results indicate that dietary levels of PL, PC and PI may affect the cod larval growth, survival and deformities. More detail studies are needed to find out the optimal levels of these important PL classes in larval cod diets.  相似文献   

18.
The effects of increasing levels of dietaryphospholipids (PL) on the reproductive performance,egg and larval quality, and lipid composition offemales of the freshwater prawn Macrobrachiumrosenbergii were investigated. Three isolipidic dietscontaining similar amounts of highly unsaturated fattyacids but varying levels of PL (0.8, 2.4 and 4.6%)were fed during 180 days to three groups of eightfemales originating from Thai ponds. No significantdifferences were observed for fecundity, egg size andhatchability, starved larvae size, and size, survivaland tolerance to stress of 8 day-old larvae.Similarly, no major differences in the lipidcomposition of the midgut gland, ovaries and muscletissue of females could be detected. Results indicatethe lack of need of dietary supplementation of PL forM. rosenbergii broodstock, as previouslyreported for earlier life stages. It is suggested thatthe basal level of 0.8% dietary PL was sufficient tomeet the dietary demands of the prawn broodstock. ThePL requirements of M. rosenbergii broodstock, ifany, may be satisfied in commercial feeds through theinclusion of ingredients containing some phospholipidsendogenously.  相似文献   

19.
Abstract. The effects of Artemia spp. and of Moina micrura from two culture sources, poultry manure and Chlorella supplemented with baker's yeast, on production of Macrobrachium rosenbergii (de Man) post-larvae (PL) were evaluated. Significantly higher production of 18·13 ± 1·45 PL/I was obtained for the larvae fed with 50:50 mixture of Artemia and Moina cultured on poultry manure compared to that for larvae fed Artemia alone (14·27 ± 1·64PL/I). Regardless of the culture source, the post-larval production was the lowest (9·23 ± 1·22 and 11·26 ± 1·33 PL/I for the larvae fed Moina. The higher dietary value of Moina cultured on poultry manure was related to the high content of n–3 HUFA particularly 20:5n-3 compared to Artemia and Moina cultured on Chlorella and yeast.  相似文献   

20.
A study was conducted to determine the effects of dietary phospholipid (PL) levels in cobia (Rachycentron canadum) larvae with regard to growth, survival, plasma lipids and enzymes of lipid metabolism. Fish with an average weight of 0.4 g were fed diets containing four levels of PL (0, 20, 40 and 80 g kg−1dry matter: purity 97%) for 42 days. Final body weight (FBW), weight gain (WG) and survival ratio were highest in the 8% PL diet group and mortality was highest in PL-free diet group. We examined the activities of lipoprotein lipase (LPL) and hepatic lipase (HL) in liver, lecithin-cholesterolacyltransferase (LCAT) in plasma as well as plasma lipids and lipoprotein. LCAT activity showed a decrease of more than two-fold in PL-supplemented diet groups compared with the PL-free diet group. HL activity was highest in the 8% PL diet group and the other three groups showed no difference. LPL activity was significantly higher in the PL-supplemented diet groups than in the PL-free diet group. The dietary intervention significantly increased plasma phospholipids and total cholesterol (TC) levels, and the higher free cholesterol (FC) level contributed to the TC level. However, the fish fed PL exhibited a significantly decreased plasma triglyceride (TG) level. The lipoprotein fractions were also affected significantly by the PL. The PL-supplemented diet groups had significantly higher high-density lipoprotein (HDL) compared with the PL-free diet group, but showed a marked decrease in very low-density lipoprotein (VLDL). The results suggested that PL could modify plasma lipoprotein metabolism and lipid profile, and that the optimal dietary PL level may well exceed 80 g kg−1 for cobia larvae according to growth and survival.  相似文献   

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