首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
2.
The nutritive values of three pelleted prepared diets, based on animal (AP), vegetable (VP) and yeast protein (YP) were studied for the sea urchin Heliocidaris erythrogramma (Val.). Fresh macroalga Ulva australis was used as a natural control diet. Triplicate groups of five animals were fed one of the four diets ad libitum every second day for 85 days. Sea urchins fed pelleted feeds had significantly higher food consumption rates (dry basis) and significantly lower total and protein absorption efficiencies compared with the algal diet. The gonad yield and gonad production efficiency in sea urchins fed the natural diet were significantly higher compared with initial group (gonad yield only) and urchins fed animal and vegetable diets, but did not differ significantly from those of the animals fed the yeast diet. Percent protein and lipid in the gonads were not affected by the dietary source. The taste and smell of gonads were generally better in sea urchins collected from the wild or fed yeast and natural diets than in sea urchins fed animal and vegetable diets. The animal protein diet was the most stable in seawater while the yeast protein diet had the poorest water stability. The results of this study suggest that development of a more stable, single‐cell, protein‐based diet has a potential to promote gonad production of H. erythrogramma.  相似文献   

3.
The effects of increasing soya bean lecithin (SL) levels (0%, 2% and 4% of diet dry matter, DM) at two fish oil (FO) levels (0% and 3% DM) on gonad index, colour and biochemical composition of Strongylocentrotus purpuratus were evaluated using a 3 × 2 factorial design with six iso‐nitrogenous formulated diets. All diets generated an increase in gonad index of more than 9%. Dietary FO had a positive effect on diet digestibility and accumulation of proteins in the gonad. Soy lecithin did not affect gonad composition, but improved its coloration, decreased gonad feed conversion ratio and increased gonad protein efficiency. There was a clear effect of diets on sea urchins gonad protein, ash and fatty acid content, in particular, decreasing the n‐3/n‐6 ratio associated with a decrease in 20:5n‐3 when SL levels increased. Nevertheless, 22:6n‐3 levels increased by week 12 in all treatments, and diets with SL increased the content of 20:4n‐6 in gonads. A decrease in bitter‐tasting amino acids such as histidine, cysteine, valine and methionine was observed in all treatments with a concomitant increase in isoleucine levels. We recommend using a diet containing 3% of FO and 2% of SL to increase food consumption, diet digestibility, improving marketable gonad colour and an increasing gonad n‐6 fatty acids and C22:6n‐3. In addition, the present study paves the way for future research in the use of FO and SL as an additive in diets for S. purpuratus towards the goal of increasing gonad size and nutritional quality.  相似文献   

4.
紫海胆黄基本营养成分的分析与评价   总被引:1,自引:0,他引:1  
为了测定紫海胆黄中的营养成分,并对其营养价值进行系统分析及合理评价,采用国家标准的生化测定方法以及美国化学分析方法(AOAC)检测海胆黄中的水分、粗灰分、粗蛋白质、粗脂肪、总糖、氨基酸、脂肪酸及矿物质。结果显示:海胆黄粉中水分含量(5.29±0.02)%,粗灰分(8.69±0.03)%,粗蛋白质(60.36±0.04)%,粗脂肪(25.32±0.09)%,总糖含量(0.044±0.002)mg/100 g;共检出18种氨基酸,总含量(46.50±0.89)%;谷氨酸含量最高,为(5.57±0.11)%;必须氨基酸占总氨基酸的(37.75±0.01)%;主要的限制氨基酸是色氨酸和亮氨酸;药效氨基酸占氨基酸总量的46.86%;蛋白质氨基酸评分(AAS)0.8,化学评分(CS)0.5;必需氨基酸指数(EAAI)为77.86;共检出30种脂肪酸,EPA(二十碳五烯酸)+DHA(二十二碳六烯酸)含量(2.43±005)%;海胆黄富含钾、磷、钠、镁、铁、锌等矿物质元素;常量元素中,磷元素含量最高,为(1 432.27±8.91)mg/100 g;微量元素中,锌元素含量最高,为(13.13±0.09)mg/100 g。研究表明,海胆黄中蛋白质含量丰富,氨基酸种类多、比例合理,脂质含量高且富含EPA、DHA等多不饱和脂肪酸,矿物质含量丰富。  相似文献   

5.
The effects of formulated feeds on Paracentrotus lividus broodstock performances and carotenoid compositions were investigated. Performance of offspring derived from each dietary treatment was compared to determine whether maternal provisioning of nutrients affected offspring development and survival under commercial culture conditions. At the end of the experimental period (3 months), urchins were induced to spawn, relative fecundity measured, and offspring derived from each treatment were reared independently and survival up to competence assessed. Carotenoid composition of the gonads was also measured. Data showed that the highest dietary protein content significantly improved somatic growth, whereas higher lipid content increased gonadal index (GI) consistent with the use of gonads as nutrient storage in sea urchins. Nonetheless, gonad lipid concentration was not significantly different between treatments indicating that higher dietary lipid content favoured gonadal size rather than increase lipid content of the gonadal tissue. Interestingly, GI and fecundity were not correlated, although the latter may have been enhanced by dietary xanthophyll. This suggests the importance of including carotenoids in broodstock diets to enhance hatchery outputs. This study also indicated that, although broodstock diet can influence fecundity, it had no significant impact on larval survival, which could instead be influenced by rearing conditions.  相似文献   

6.
The aim of this work was to assess the potential use of different dried macroalgae as food in the rearing of Paracentrotus lividus. Growth, consumption and food conversions were compared in adult sea urchins fed with fresh or dried thalli of four macroalgae species. Six experimental diets were tested: (a) fresh Palmaria palmata; (b) fresh Saccharina latissima; (c) dry P. palmata; (d) dry S. latissima; (e) dry Laminaria digitata and (f) dry Grateloupia turuturu. Linear growth rates were similar for all treatments. Specific growth rate was higher in sea urchins fed with fresh P. palmata, but no difference was found between animals fed with fresh S. latissima and those fed with dried diets. Regarding daily food consumption (DFC), sea urchins consumed the same amount of dried macroalgae as fresh but exhibited a higher food conversion efficiency (FCE) when fed with fresh P. palmata. However, this FCE was only significantly higher when compared to sea urchins fed with dry L. digitata. Dried G. turuturu is not a suitable diet due to its rapid degradation after rehydration. The results suggest that P. lividus adults can be reared on dried macroalgae thalli without detriment to their somatic growth, especially over short periods. The low cost of feeding sea urchins with this diet could help small shellfish farmers to diversify their production into echinoculture.  相似文献   

7.
Adult (Strongylocentrotus purpuratus) purple sea urchins were fed giant kelp (Macrocystis pyrifera) and sea lettuce (Ulva lactuca) macroalgae that were unenriched and enriched with nutrients. Urchins were fed over 10 weeks (5% body weight per day) under laboratory conditions to determine the effect of macroalgae species and treatment (enriched and unenriched) on growth, gonad index and gonad quality. Significant differences were observed when urchins were fed enriched Macrocystis pyrifera (MPE). Gonad weight increased from 0.7 ± 0.1 g (mean ± SD) to 5.9 ± 1 g, and gonad index increase from 3.5 ± 1.5% to 14.9 ± 2.3% over 10 weeks. Significant differences were also noted in gonad quality, and gonad colour and firmness were better in urchins that were fed unenriched M. pyrifera (MPUE) and MPE – whereas texture did not differ between M. pyrifera treatments and unenriched U. lactuca (ULUE). With regard to taste, gonads were sweeter in MPE‐fed individuals. Enriched U. lactuca (ULE) failed to grow gonads significantly; as a result, their quality was unacceptable for the market. These results suggest that S. purpuratus experience increased gonad production and quality in short periods when fed nutrient‐enriched M. pyrifera.  相似文献   

8.
This study compared the growth of sea urchin Paracentrotus lividus larvae cultured using two different rearing methods: a variable method based on a variable amount of feed (microalgae) and seawater exchange (30% or 50%) established according to the phytoplankton concentration in the larval cultures and a fixed method characterized by a fixed amount of feed and seawater exchange. Three microalgae diets, Isochrysis sp. (Tahitian strain, T‐Iso), Chaetoceros gracilis and a 50:50 mixed diet, were tested with both rearing methods. Larval development and survival were assessed at the 6‐arm pluteus stage (P6), competence (Cp) and metamorphosis (Mt). Data showed that the variable method reduced the requirements for phytoplankton and seawater exchange. Indeed, through the optimization of feed rations, it was possible to reduce the production of debris and settled phytoplankton, minimizing the need for water exchanges. Higher larval survival resulted at Cp and Mt stages for those reared with the variable method as opposed to the fixed one. Survival and development were also influenced by the tested dietary treatments: at Mt stage, the mixed diet resulted in a higher larval survival (63.3 ± 8.9%) than T‐Iso (19.7 ± 12.1%) and C. gracilis (23.4 ± 15.1%) (< 0.05). These results suggest that the use of the variable method improves the larval survival and development and also it reduces resource consumption (phytoplankton, seawater use and work effort), which in turn could potentially improve the hatchery production of P. lividus.  相似文献   

9.
This study provides a robust relationship between feed intake (FI), gonad growth (GG), and feed conversion ratio (FCR) of cultured adult green sea urchin Strongylocentrotus droebachiensis. Sea urchins (test diameter: ∼ 54 mm and live weight: ∼ 70 g) were collected in the wild and cultured either individually or subjected to one of three stocking densities, i.e. low 2.5 (N = 36), medium 3.7 (N = 54), or high 7.3 (N = 108) kg animal per m2. Animals were fed a prepared diet in excess for 56 days at 6.5-4.5 °C. The gonad index (GI) more than doubled during the 56 day trial. The final mean values of GI (17-18%), FI (0.3-0.4 g feed per animal per day), and FCR (∼ 3 g feed per g increase in gonad weight) were statistically similar between individual and stocked animals. Based on data from the individually cultured sea urchins, the relationship between daily FI (g feed per animal) and GG (g gonad increase per animal) could be described by the equation: GG = 0.619FI − 0.097 (R2 = 0.533, P < 0.001). In conclusion, marketable sizes of green sea urchin perform well in raceways at densities of 7-8 kg animal per m2 without adverse effects on FI, GG, and FCR.  相似文献   

10.
This study investigated the effect of dietary arachidonic acid (ARA, 20:4n‐6) on final maturation, spawning performance and composition of the gonad of black sea urchin (Diadema setosum). Four different dietary ARA levels of 0.3 g/kg (Control diet), 1.4 g/kg (ARA 1.4), 2.5 g/kg (ARA 2.5) and 3.7 g/kg (ARA 3.7) were prepared and tested in this feeding trial for 90 days. The result showed that growth in terms of weight was not relatively affected by dietary ARA. Gonadosomatic Index (GSI) of animals were gradually increased in all the diets throughout the trial. The highest GSI level (25.7 ± 3.16%) was observed in animals fed with the diet ARA 1.4. ARA content in the gonad proportionally increased with dietary ARA levels. The highest larval survival rate (85.5 ± 5.67%) was found in diet ARA 2.5. The results of this study indicate that ARA plays an important role in the reproduction functions of black sea urchin and supplementing an appropriate level of ARA in the broodstock diet could induce the final maturation and improve reproduction of black sea urchin, but a higher level of ARA (3.7 g/kg) seems to have a negative effect on both growth rate and GSI.  相似文献   

11.
A greater understanding of dietary protein and carbohydrate levels with regard to gonad production in Strongylocentrotus purpuratus would increase our nutritional knowledge of this sea urchin and guide the development of formulated diets for such aquaculture target species. A total of 255 purple sea urchins were captured from Ensenada Bay, Mexico, and maintained in 200‐L tanks for 9 weeks. Formulated diets that contained 30%, 26%, 23%, 20% and 17% of protein and 42%, 46%, 50%, 54% and 58% carbohydrates were offered ad libitum. Survival was affected by diets; urchins that were fed high‐protein–low‐carbohydrate diet experienced decreased survival. No significant differences were found in gonad index, but gonad production efficiency was lower in urchins that were fed a medium‐low‐protein–medium‐high‐carbohydrate diet. Urchins that were fed high carbohydrate levels utilized protein more efficiently and showed better digestibility of the diet and protein. These data suggest that all of our diets support gonad growth, but in terms of consumption, a diet that contains protein levels of 17% and 23% with carbohydrate levels of 50% and 58% are beneficial for S. purpuratus.  相似文献   

12.
This study investigated growth and gonad production of Tripneustes gratilla fed four protein‐rich artificial diets supplemented with varying amounts (0%, 5%, 15% and 20% weight/weight (w/w); designated 0, 5, 15 and 20U, respectively) of the macroalga Ulva over a 12‐week period. Gonad size, texture, colour and a number of production performance parameters were quantified and compared with urchins fed fresh Ulva (FU) and a combination of FU and artificial feed (FB). All artificial diets significantly ( 0.05) increased gonad somatic indices (GSI) compared with the FU treatment. The 20U treatment increased GSI by 205% by week 9, compared with a 57% increase in the GSI of urchins fed FU. Gonad colour was calculated using three colour parameters, namely L* (lightness), a* (redness) and b* (yellowness). Whereas L* and a* values did not differ significantly between treatments, b* values for all treatments, with the exception of the 20U and FB treatments, were significantly ( 0.05) lower or less yellow than the FU treatment by week 12. These results show that we have successfully formulated a feed (20U) which can produce commercially acceptable gonads in terms of both size and colour, indicating the potential for this artificial feed to support commercial echinoculture.  相似文献   

13.
In this study, we demonstrate how stable carbon (C) and nitrogen (N) isotope analysis can be used to estimate the allocation of specific dietary ingredients, incorporated into four artificially formulated feeds supplemented with varying amounts of dried seaweed Ulva armoricana (0, 50, 150 and 200 g/kg), to the production of gonads by Tripneustes gratilla over a 20‐week growth trial. Results indicate that U. armoricana is an important dietary ingredient for gonad production, accounting for an average of 37.33 ± 1.03% of the isotopic signal recorded for gonads at the end of the growth trial. This is significantly more than fish meal and soya, which only contributed an average of 11.40 ± 1.81 and 3.80 ± 0.09%, respectively, of the isotopic signal of the gonads. Maize and wheat each account for almost 25% of all the dietary ingredients used to formulate the feeds, but their relative contribution to gonad production only averaged 8.55 ± 0.58 and 3.80 ± 0.05%, respectively, among the diets. This indicates that, at least for gonad development, these ingredients may not be required at such high levels. These findings support previous data on the importance of Ulva in abalone and urchin diets, and demonstrate the value of stable isotope analysis for assessing the contribution of specific dietary ingredients in new feed formulations, particularly where growth of specific tissues is being investigated.  相似文献   

14.
We evaluated the effect of different concentrations of 5′‐inosine monophosphate (IMP) and 5′‐guanosine monophosphate (GMP) on the growth, immunity and muscle composition of turbot Scophthalmus maximus. Eight diets (containing no IMP or GMP, or 0.5 g/kg IMP, 1.0 g/kg IMP, 2.0 g/kg IMP, 0.5 g/kg GMP, 1.0 g/kg GMP, 2.0 g/kg GMP, or 0.5 g/kg IMP plus 0.5 g/kg GMP) were prepared. A total of 360 fish (average body weight of 105 g) were randomly selected and placed in groups into 24 plastic aquaria (8 treatments × 3 replicates × 15 individuals per plastic aquaria). The tanks were maintained at the temperature of 15 ± 2°C. The experimental diets were fed for 60 days. The specific growth rate (SGR) was significantly higher in S. maximus fed with IMP or GMP compared with fish fed neither IMP nor GMP. The highest SGR was observed in fish fed with 1.0 g/kg IMP. Supplementation with these dietary nucleotides had a positive, but not significant effect on the activity of superoxide dismutase, alkaline phosphatase and acid phosphatase. There was a significant difference in the moisture and crude lipid content of muscle from S. maximus fed the different diets compared with control fish. The highest moisture content was 83.44 for a diet of 0.5 g/kg IMP plus 0.5 g/kg GMP, which was also significantly higher when compared to fish fed alternative diets. The crude lipid content of S. maximus fed diets containing either IMP or GMP was significantly higher than those fed diets without IMP or GMP. Thus, according to these results, the optimal level of dietary IMP is 1.0 g/kg, which correlates with the largest increase in growth performance of S. maximus.  相似文献   

15.
Geoduck clams are amongst the most valuable cultured shellfish available on the world market, driving interest in the establishment of the native New Zealand species, Panopea zelandica (Quoy & Gaimard, 1835), as a candidate for aquaculture. A critical element of domestication is the effective management of breeding stock to optimize gamete and offspring quality. To develop a reliable broodstock conditioning protocol for P. zelandica, we investigated the biochemical composition of geoducks exposed to nine factorial treatment combinations of temperature (7.5, 11.5 and 16.5°C) and feeding ration [10 000, 50 000 and 100 000 cells mL?1 of a (1:1 cell count) mixture of Tisochrysis lutea and Chaetoceros muelleri]. In addition, a reference group of geoducks was conditioned in an aquaculture pond‐nursery system, providing a dilute, mixed phytoplankton culture at ambient temperature. Glycogen, protein, lipid and fatty acid contents of flesh and viscera were measured at days 0, 36 and 73 of conditioning. Glycogen, protein and lipid analyses indicated that geoducks within all treatments achieved a positive energy balance, except for those in the treatment combining the highest temperature and lowest feeding ration. Comparisons of fatty acid profiles of animals among treatments and with the reference group revealed that eicosapentaenoic (EPA, C20:5n‐3), docosahexaenoic (DHA, C22:6n‐3) and arachidonic (ARA, C20:4n‐6) fatty acids were important contributors to gametogenic development for geoduck conditioning.  相似文献   

16.
Knowledge on the biochemistry of proteins and amino acids (AA) of eggs and larvae of echinoids is scarce and the possibility to modify their profiles by diet manipulations is unknown. The protein content of eggs, prisms and pre‐plutei and the amino acid composition of eggs of Paracentrotus lividus from captive broodstock fed prepared diets were analysed and compared with the ones obtained from wild broodstock. Diets differed on protein source (fish or soy meals) and on protein content (10–40% dry weight – DW). Total and soluble protein content of both eggs and larvae was higher than 400 g kg?1 DW and 200 g kg?1 DW respectively. Glycine was the most abundant free AA. Very few differences were found among P. lividus eggs and larvae biochemical parameters, suggesting that their AA composition can hardly be changed by broodstock diet manipulations.  相似文献   

17.
The effect conjugated linoleic acid (CLA) accumulation in fish fillet on sensory and texture attributes has been evaluated. Fish were fed diets with graded levels of CLA, which were administered for different durations prior to harvest. Fish were sampled for fillet proximate composition and fatty acid profile for sensory and texture parameters at the end of the trial. Growth performance, feed conversion ratio and muscle proximate composition were not affected by dietary treatments. Muscle fatty acid profile was not affected by dietary treatments despite the increase in saturated fatty acids in fish fed diet with 10 g kg−1 of CLA for 16 weeks before harvest. Besides, the deposition levels of CLA isomers increased gradually depending on the CLA treatment, reaching its maximum level in fish fed 10 g kg−1 CLA diet for 20 weeks before harvest. Fish fed 10 g kg−1 were juicier (P < 0.05) compared with control group, whereas fish fed 5 g kg−1 CLA diet were less (P < 0.05) chewy than fish fed control diet regarding sensory attributes. Texture parameters were not significantly affected by dietary CLA. These results suggest that market size European sea bass could successfully incorporate CLA isomers with some minor positive effects on sensory analyses.  相似文献   

18.
The sea louse Caligus rogercresseyi is a major threat to Chilean salmonid farming. Pyrethroids have been used for anticaligus treatments since 2007, but have shown reduced effect, most likely due to resistance development. Pyrethroid resistance is also a known problem in Lepeophtheirus salmonis in the Northern Hemisphere. This study describes the development of deltamethrin resistance in C. rogercresseyi based on bioassays and usage data for pyrethroids in Chilean aquaculture. These results were compared to bioassays from L. salmonis from Norway and to Norwegian usage data. Available deltamethrin bioassay results from 2007 and 2008, as well as bioassays from Norway, were collected and remodelled. Bioassays were performed on field‐collected sea lice in region X in Chile in 2012 and 2013. Bioassays from 2007 were performed prior to the introduction of pyrethroids to the Chilean market. Both the results from 2008 and 2012 showed an increased resistance. Increased pyrethroid resistance was also indicated by the increased use of pyrethroids in Chilean aquaculture compared with the production of salmonids. A similar trend was seen in the Norwegian usage data. The bioassay results from Chile from 2012 and 2013 also indicated a difference in the susceptibility to deltamethrin between male and female caligus.  相似文献   

19.
Megalocytiviruses cause high mortality diseases that have seriously impacted aquaculture, with the most frequent outbreaks occurring in East and South‐East Asia. The international trade of juvenile fish for food and ornamental aquaculture has aided the spread of these viruses, which have spread to Europe and Australia and other regions. Australian freshwater fishes were examined for susceptibility to infection with the exotic megalocytivirus, dwarf gourami iridovirus (DGIV), which belongs to a group with the type species, Infectious spleen and kidney necrosis virus (ISKNV). Fish were held at 23 ± 1 °C and challenged by intraperitoneal (IP) injection or by cohabitation with Murray cod, Maccullochella peelii (Mitchell) infected with DGIV. A species was deemed to be susceptible to DGIV based on evidence of viral replication, as determined by qPCR, and megalocytic inclusion bodies observed histologically. Horizontal transmission occurred between infected Murray cod and golden perch, Macquaria ambigua (Richardson), Macquarie perch, Macquaria australasica (Cuvier) and Murray cod. This indicated that DGIV shed from infected fish held at 23 °C can survive in fresh water and subsequently infect these naïve fish. Further, DGIV administered IP was highly pathogenic to golden perch, Macquarie perch and Murray cod. Compared to these species, the susceptibility of southern pygmy perch, Nannoperca australis (Gunther) was lower. Freshwater catfish (dewfish), Tandanus tandanus (Mitchell), were not susceptible under the experimental conditions based on the absence of clinical disease, mortality and virus replication. This study showed the potential risks associated with naïve and DGIV‐infected fish sharing a common water source.  相似文献   

20.
The genetic diversity of the growth hormone gene in domesticated red sea bream (pmaGH) was evaluated using a minisatellite DNA marker located in intron 3 (pmaGH22) and nucleotide sequences. The number of alleles of pmaGH22 was largely decreased in domesticated strains of red sea bream, and the possibility of selection pressures was also detected based on the analysis of the Hardy–Weinberg equilibrium in some strains. However, each strain inherited a small number of alleles of pmaGH22, and the entire domesticated population (combining all strains) showed a large number of alleles (n = 17), similar to the allelic richness of the wild population (n = 18.5). Based on nucleotide sequencing analysis, three synonym mutations were found in the coding regions, and also several SNPs and indels were found in the noncoding regions. In addition, four genealogies of growth hormone haplotypes were identified based on principal coordinate analysis, and these genealogies of pmaGH partly reflected allele size ranges of pmaGH22. Several haplotypes shared alleles of pmaGH22, and also fragment size homoplasy in pmaGH22 was suspected. These alleles of pmaGH22 and the haplotypes will be a useful indicator for divergence of pmaGH and for broodstock individual selection with minimum inbreeding effect.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号