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太平洋牡蛎工厂化育苗技术研究(上)太平洋牡蛎是广盐性、广温性的内湾品种。具有个体大、生长快、产量高、适应性强的特点,现已被世界沿岸国家所普遍养殖,是目前世界上养殖牡蛎优良品种之一。为了改良牡蛎养殖品系,开发利用浅海资源,福建省于1982年和1983年... 相似文献
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饲在太平洋牡蛎人工育苗过程中,海水单胞藻是不可替代的活性生物饵料。不同种类的海水单胞藻在适口性、营养价值、消化难易及对牡蛎幼虫的毒性等方面情况差异,这必然要影响到牡蛎浮游幼虫的生长变态及成活率,从而影响到育苗结果。在本试验中,使用包括云微藻在内的六种在贝类育苗中常用的海水单胞藻作投喂试验,观察、比较了太平洋牡蛎浮游幼虫的生长发育及成活情况,并据此对这几种海水单胞藻及其组合的优势、生产上的适用性进行评判。目前,大部分太平洋牡蛎育苗场在育苗生产中使用云微藻,甚少使用其它藻类虽然也能够培育出种苗,但使… 相似文献
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近几年来,水产养殖上新增加太平洋牡蛎的养殖,发展形势看好,方兴未艾,因此,提供健壮,抗病害,生长快的苗种支持养殖业的发展也成当务之急,本文就如何进行太平洋牡蛎的人工育苗,提高人工育苗的苗种质量作了探讨。 相似文献
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长牡蛎大面积人工育苗的研究 总被引:1,自引:0,他引:1
前言长牡蛎[Crasostrea gigas(Thonberg)](日本称真牡蛎、欧美称太平洋牡蛎)是广温性、广盐性的海产贝类。具有体型大、生长快、产量高、经济效益好,又是人们喜爱的海产佳肴,也是我国重点引进开发的海产浅海养殖新品种。 相似文献
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为研究鲈鲤(Percocypris pingi)苗种的生长特性,开发鲈鲤育苗技术,采用水泥池流水单养模式,在自然水温条件下,开展了10日龄至110日龄鲈鲤苗种培育试验。经过100 d的培育,鲈鲤鱼苗体质量从(46.45±4.03)mg增加到(2600.09±105.18)mg,平均体长从(16.22±0.46)mm增长到(50.78±2.97)mm,平均成活率为82.00%;体质量变异系数在4.05%~24.80%,体长变异系数在2.49%~7.32%,体质量变异系数大于体长变异系数;体质量变异系数整体呈现先升高后降低的变化趋势,体长变异系数整体变化较为平缓,在整个培育阶段,鲈鲤种群生长离散呈现从加剧到减弱的变化规律;体质量特定生长率在(0.91±0.49)%/d~(7.75±2.18)%/d,体长特定生长率在(0.47±0.29)%/d~(1.94±1.46)%/d,体质量特定生长率大于体长特定生长率;在水温16.8~23.0℃条件下,鲈鲤生长状况良好,特定生长率相对较高,当水温高于23.0℃之后,特定生长率呈降低趋势,表明16.8~23.0℃是鲈鲤鱼苗适宜的生长水温范围;肥满度变化范围在(1.09±0.10)~(2.85±0.18)g/cm^3,肥满度变化呈现先升高后降低的变化趋势;体长(x)和体质量(y)的拟合方程为y=0.0015x^3.7566(R^2=0.9806),b值为3.7566;全长(y)和体长(x)的拟合方程为y=1.223x-0.5055(R^2=0.9908)。试验结果表明,鲈鲤苗种在水泥池流水单养模式及自然水温条件下生长状况良好,16.8~23.0℃是鲈鲤苗种的适宜生长水温。 相似文献
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Heterobranchus longifilis larvae were reared over a 35 d period to evaluate the effects of stocking densities and feeding regimes on growth and survival. In experiment 1, larvae (12.3?±?2.1 mg) were stocked into glass aquaria at densities of 1, 2, 5, 10, 15, 20, and 25 larvae L?1. Larvae were fed on Artemia nauplii ad libitum. Significant variations in terms of growth performance and feed utilization occurred at all levels of density treatments. Specific growth rate (SGR), body weight gain (BWG), and feed efficiency (FE) of the larvae decreased significantly as density increased. However, survival rate increased with the increase of stocking density. In experiment 2, larvae (13.4?±?1.1 mg) stocked at a density of 15 larvae L?1, in the same conditions as experiment 1, were fed on three different regimes: Artemia nauplii; 35%?protein beef brain; and 35%?protein commercial catfish feed (CN+). SGR, BWG, and coefficient of variation (CV) of larvae fed on Artemia nauplii were significantly higher than those fed on beef brain and CN+. The survival rate of larvae fed on beef brain was significantly higher (88.40?±?9.75%) than those of Artemia (69.21?±?6.69%) and CN+ (40.40?±?6.22%). The results of this study suggest that the optimum stocking density is 15 larvae L?1 and the beef brain can be used as alternative feed to Artemia in rearing H. longifilis larvae. 相似文献
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ABSTRACT: For the development of a stepwise cryopreservation technique for larvae of the Pacific oyster Crassostrea gigas , various conditions were examined. Larvae at 9, 12, 15, 18 and 21 h after insemination were cooled at a rate of −1°C/min (seeding at −8°C for 15 min) and then plunged into liquid nitrogen at −35 or −40°C using 1.5 M dimethyl sulfoxide (DMSO) and 250 mM trehalose as cryoprotectants. Among these larvae, 15 h after insemination (the trochophore stage before formation of the shell gland) showed the highest motility and the best external appearance after thawing. Trochophore larvae were cryopreserved in preservation media containing different dilutions (1/4, 1/6, 1/8, 1/10 and 1/30) of seawater. Larvae preserved in the 1/4 seawater medium showed the highest appearance of shelled larvae 4 days after thawing. Trochophore larvae reared in seawater at 21, 25 or 29°C were cryopreserved for 8 months and then reared at 26°C after thawing. Larvae reared at 25°C showed the highest survival rate and normal larval ratio at day 6 after thawing, although larvae reared at 21°C showed the highest rates until day 4. One larva developed at 25°C succeeded to settle. 相似文献
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Enhancing growth and resistance to Vibrio alginolyticus disease in catarina scallop (Argopecten ventricosus) with Bacillus and Lactobacillus probiotic strains during early development
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Fernando Abasolo‐Pacheco Ángel I Campa‐Córdova José M Mazón‐Suástegui Dariel Tovar‐Ramírez Rubén Araya Pedro E Saucedo 《Aquaculture Research》2017,48(9):4597-4607
In bivalve aquaculture, selecting suitable probiotic treatments can be crucial for improving hatchery‐rearing of larvae and juveniles. We assessed the potential of five bacterial strains, previously selected in vitro, to improve survival, growth and resistance of catarina scallop Argopecten ventricosus during early and late larval and juvenile developmental stages, as well as during exposure to the pathogen Vibrio alginolyticus. Hatchery‐reared larvae and juveniles were treated with eight treatments of single or combined strains of Bacillus and Lactobacillus at 1 × 106 CFU mL?1 every 48 h for 9 days (larvae) and 21 days (juveniles). Compared with the control, significantly higher survival and growth in size and weight of early veliger larvae occurred with the antibiotic and the RL5 (Lactobacillus graminis) treatments. Significantly enhanced settlement of pediveliger larvae occurred with a different probiotic strain, the mix of Lactobacillus and Bacillus (MIX‐LB), while higher survival and growth of early juveniles occurred with C3 (Lactobacillus plantarum). The mix of Bacillus (MIX‐B) significantly increased survival of juveniles from V. alginolyticus after 120‐h infection, consistent with maximum activity of superoxide dismutase enzyme. In contrast, all untreated and infected scallops died by 96 h. The three Bacillus strains performed poorly when used as single treatments and when given to early developing larvae. Our results indicate that the action mechanism of probiotic strains is stage specific and strain specific, generating different responses by the host, including improved survival and growth (likely from better nutrient assimilation) and higher resistance against pathogens (possibly from strengthening the immune system). 相似文献
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Effect of the supplementation of live preys enriched in cod liver oil on the survival rate,growth and fatty acid profile of meagre (Argyrosomus regius) larvae
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Houda Saidi Rocío Morales‐Medina Azeddine Abrehouch Soumia Fahd Emilia M Guadix Escobar Raúl Pérez‐Gálvez 《Aquaculture Research》2018,49(3):1133-1141
First‐feeding diets employed in the rearing of meagre (Argyrosomus regius) larvae are based on live preys that are commonly enriched to compensate for their deficiency of essential fatty acids. A feeding trial was conducted on meagre larvae (Argyrosomus regius) fed rotifer (Brachionus plicatilis) and Artemia salina enriched in lipids from an emulsion of cod liver oil (CLO) and a commercial product (CP). The effect of both enrichment products was evaluated on the survival rate, size and lipid composition of meagre larvae. The results showed that larvae fed CLO presented significant higher values of survival rate (35.0 ± 3.2%) and larval size (12.06 ± 1.17 mm) at the end of the experiment, compared to the CP diet (26.0 ± 2.5%, 11.41 ± 0.91 mm, respectively). Both zootechnical parameters were related to the content of polyunsaturated fatty acids in the larvae. Indeed, the larvae fed CLO presented a higher ratio DHA/EPA than those enriched in commercial product (0.82 ± 0.18 and 0.38 ± 0.12 at 26 days after hatching, respectively). Both larval groups presented similar body content of arachidonic acid (1.4 wt.% on average at 26 days after hatching), regardless the enrichment source. From all above, we can conclude that the enrichment of live preys with an emulsion of cod liver oil is an economically viable alternative to commercial products. Indeed, cod liver oil emulsions are able to fully meet the requirements for fatty acids of meagre larvae. Furthermore, cod liver oil is easily available from fish processing facilities. 相似文献
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Variations in Bacterial Community of Rearing Water and Gut of Common Dentex,Dentex dentex (Linnaeus 1758), Larvae Using Three Microalgae Management Approaches
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Gemma Giménez Papiol Ana Roque Alicia Estévez 《Journal of the World Aquaculture Society》2018,49(5):953-963
Microorganisms present in the rearing water colonize the gut of first feeding larvae and represent the first barrier against opportunistic pathogens. The aim of the experiments presented herein was to standardize a protocol for the management of rearing water and microalgae suitable for the larval rearing of common dentex. In Experiment 1, bacteria–algae interactions were tested using a monospecific microalgal community, Tetraselmis chuii, suitable for nutritional experiments and with known antibacterial activity. In Experiment 2, the evolution of the bacterial community and larval performance (growth and survival) were monitored daily, in three conditions: (1) mature water: T. chuii was added 5 d before the rearing of common dentex larvae, (2) green water: T. chuii was added 1 d before, and (3) clear water: no T. chuii addition. The results show the influence of the presence of T. chuii on the evolution of the bacterial communities, both in terms of bacterial density and morphology, and indicate green water is the most suitable water treatment for management of larval rearing for common dentex. 相似文献
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Innovative Egg Custard Formulation Reduced Rearing Period and Improved Survival of Giant Freshwater Prawn,Macrobrachium rosenbergii,Larvae
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This study was conducted to determine the performance of new egg custard formula to replace Artemia sp. on the growth and survival of the giant freshwater prawn, Macrobrachium rosenbergii, larvae. Five experimental diets were tested with triplicate treatments: ART (Artemia sp.), ART‐MIX (Artemia sp. + egg custard MIX: a mixture of shrimp, squid, and bivalve meal‐based egg custard, with palm oil), ART‐PBM (Artemia sp. + PBM, poultry byproduct meal‐based egg custard with fish oil), egg custard MIX only, and egg custard PBM only. All experimental diets were tested after 9 d (stage VI) of feeding Artemia sp. to prawn larvae. The stocking density was set at 100 larvae/L in a clear water tank culture system. Results indicated that the highest survival was recorded in the treatment of ART‐PBM (46.07 ± 0.84%) and the lowest was in the MIX treatment (8.87 ± 0.51%). ART‐PBM and ART‐MIX diets successfully reduced the rearing period and improved survival from larval to postlarval stage by 19 and 65%, respectively, compared with the ART diet. However, the use of MIX and PBM alone increased the rearing period up to 11%. The feeding regime of ART‐PBM and ART‐MIX has provided nutritional advantages and can be successfully practiced in the hatchery of M. rosenbergii larvae. The innovative approach of using PBM and palm oil in the egg custard formulation in this study can provide prawn hatchery operators with more options in terms of dietary ingredients and cost‐effective solutions. 相似文献
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Ludwig C. A. Naegel 《Aquaculture Economics & Management (Blackwell Science)》2013,17(2):211-223
The consumption of electricity and propane for producing larvae and postlarvae of the whiteleg shrimp (Litopenaeus vannamei) was examined in a commercial shrimp hatchery on the Baja California Peninsula of Mexico. Between January and August 2005, 6 × 106 postlarvae (average age PL16) were produced from 1.43 × 109 nauplii. During that production period, the hatchery used 2.48 × 109 kcal of fossil fuel energy (30% for electricity, 70% for liquid propane), which was equivalent to 16% of the operating costs. Electricity was used mainly for larval and postlarval rearing (36% and 10%) and microalgae culture (27%). During this production period, 1.47 × 109 kcal of propane were consumed for heating daily more than 600 m3 seawater daily. Of that total, 33% was used for broodstock maintenance, 65% for larvae culturing, and 2% for postlarvae rearing. With increasing costs for shipping postlarvae to the mainland Mexican coastal areas (15% of operating costs) and the need to remain competitive with hatcheries in the coastal areas of Sonora and Sinaloa, alternative energy sources to reduce overall operational costs in hatcheries of Baja California Sur are discussed. 相似文献