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1.
罗氏沼虾工厂化育苗试验 总被引：2，自引：0，他引：2
利用对虾育苗场的设计进行罗氏沼虾工厂化育苗试验，于１３６ｍ＾３水体中投放状幼体１４３８万尾，育出商品仔虾９６４万尾，幼体培育成活率为６７％，平均每尾亲虾出苗４７２５尾，单位水体平均出苗量为７．０９万尾，最高为１０．２万尾／ｍ＾３。从４月上旬到５月下旬，罗氏沼虾雌性亲虾可抑卵三次以上，前后抱卵批次所孵出的幼体质量没有明显差异。试验还证明，幼体培育池内氨氮浓度高达１０５６．４μｇ／ｌ对成活率没有多大曩 相似文献
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不同开口饵料对克氏原螯虾幼虾发育及消化酶活性的影响 总被引：3，自引：0，他引：3
实验采用丰年虫无节幼体、草鱼鱼糜、水蚯蚓、1号人工配合饲料和2号人工配合饲料为克氏原螯虾的开口饵料,观察幼虾存活率和生长情况。经过40d的培育,对幼虾的胃蛋白酶、胰蛋白酶、淀粉酶和脂肪酶的活力进行测定。结果表明：投喂丰年虫无节幼体的实验组幼虾存活率最高,为75,增重率和增长率也最大,分别为4746.00和171.00。幼虾的胃蛋白酶活性与投喂的饵料密切相关,投喂丰年虫无节幼体组幼虾的胃蛋白酶和胰蛋白酶活性分别为2.18U/mgprot和0.96U/mgprot,极显著高于投喂草鱼鱼糜实验组。实验的5种开口饵料中,丰年虫无节幼体是克氏原螯虾幼虾的最佳开口饵料。摄食丰年虫无节幼体可能提高了主要消化酶的活性,从而促进了克氏原螯虾幼体的生长。 相似文献
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真鲷全人工工厂化育苗技术研究 总被引：6，自引：0，他引：6
利用人工培育和海捕的真鲷亲鱼，进行自然产卵，而后观察了真鲷胚胎发育过程，用小型轮虫、微胶囊饵料配合蛋黄，海湾扇贝卵作为开口饵料，进行鱼苗前期培育，以鱼、虾、蟹肉糜为饵料进行后期培育。在４３４．８ｍ＾３水体中，一次育出体长０．４９￣２．５０ｃｍ的真鲷仔稚鱼４８４万尾。专家鉴定认为，单位水体育苗量进入国际先进行列，居国内领先水平。 相似文献
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人工海水培育南美白对虾幼体的初步研究 总被引：3，自引：0，他引：3
南美白对虾无节幼体1200万尾，用人工配制海水进行幼体培育试验。以湛江等鞭金藻和角毛藻为开口饵料，培育出商品仔虾435万尾，平均成活率为36％。 相似文献
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刀额新对虾工厂化育苗技术 总被引：3，自引：1，他引：2
培育刀额新对虾无节幼体时以单细胞藻类作开口饵料,有利于提高成活率;糠虾期、仔虾期在低盐度（Ｓ１８．６６）中生长速度快于在高盐度中,且在逐级递降的淡化过程中,仔虾的成活率较高,这期间投喂轮虫,适合于糠虾、仔虾捕食,轮虫蚕食水中的有机碎屑,有利于水质的改善。 相似文献
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通过脊尾白虾幼体饵料搭配的比较试验,研究了海水小球藻、中肋骨条藻分别与虾片和卤虫无节幼体搭配投喂对脊尾白虾幼体的变态速率、存活率及体长变化的影响。结果表明,单一使用虾片的育苗效果较差,幼体发育至2期溞状幼体后开始大量死亡,只有约30%的幼体变态成3期溞状幼体;投喂卤虫无节幼体与中肋骨条藻搭配组的脊尾白虾幼体组在第8d时有46%的幼体变态为仔虾,至第10d时幼体100%变态为仔虾;此外,卤虫无节幼体与中肋骨条藻搭配组幼体的存活率为92%,其幼体在1期仔虾平均体长为5.199mm,平均日增长达到0.3079mm/d。由此可见,卤虫无节幼体与中肋骨条藻搭配有利于脊尾白虾幼体的生长发育,可用于脊尾白虾育苗生产。 相似文献
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开口微囊饵料在罗氏沼虾育苗中的应用 总被引：1，自引：0，他引：1
利用杭州高成添加剂生产的“高成”牌罗氏沼虾幼体开口微囊饵料,进行罗氏沼虾育苗试验。结果：“高成”牌幼体微囊饵料替代６０％的卤虫卵,仔虾成活率达６０％以上,成本降低１／３～１／２。 相似文献
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报道了中国对虾保水育苗的工艺流程及管理措施：海水沉淀２４ｈ后，用１０００目网过滤；放养无节幼体密度为１０万尾／ｍ＾２；水温控制：无节幼体２０～２２℃，蚤状幼体２２～２３℃，糠虾期２３～２４℃，仔虾期２５～２５．５℃；以较强光照培育单胞藻；连续充气，其强度随发育阶段而逐渐增强；前期主投小硅藻，后期主喂卤虫，辅喂蛋黄、蛋羹，严格控制投喂量。经１８天培育，出苗率达５５％，单位水体出苗量在４．９～６．４成 相似文献
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1993～1994年山东省中国对虾育苗期病毒感染的流行病学调查 总被引：1，自引：0，他引：1
１９９３年和１９９４年育苗期，在山东省十余家育苗场采集了亲虾、受精卵、无节幼体、蚤状幼体、糠虾幼体和仔虾等样品共５６份。组织病理学切片观察说明，所有样品均未检查出对虾暴发性流行病病原ＨＨＮＢＶ的病理变化；ＨＰＶ的病理变化主要在亲虾、糠虾幼体和仔虾中检出，蚤状幼体有ＨＰＶ感染的可疑情况。１９９４年，５．５％的糠虾幼体和５．１％的仔虾检出有ＨＰＶ的感染。在糠虾和仔虾阶段，海捕亲虾苗种的ＨＰＶ带毒率为４．０％，越冬亲虾苗种的带毒率为６．２％。ＨＰＶ和ＨＨＮＢＶ的单克隆抗体ＥＬＩＳＡ检测方法表明有３个样品为可疑的ＨＨＮＢＶ阳性；有１２．５％～２５％的糠虾期育苗池和７０％的仔虾期育苗池存在有ＨＰＶ的感染。 相似文献
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为进一步查明对虾"玻璃苗"的主要致病原,实验通过对河北省沧州市凡纳滨对虾苗种玻化症进行了流行病学调查及病原、病理分析。结果发现,患病虾苗表现为活力降低、厌食直至空肠、空胃,虾体消瘦、暗浊;肝胰腺组织坏死性萎缩、轮廓模糊、颜色变浅呈淡黄色,甚至肝胰腺区由正常的饱满褐色组织变为无组织结构的"玻璃化"状态。组织病理观察结果显示,患病对虾肝小管上皮细胞坏死、脱落,肝小管中充斥大量的碎片组织,并逐步褐化、黑化,甚至肝小管组织大面积坏死,留有连片玻璃样均质化区域;肠道内充斥大量的组织碎片,绒毛膜脱落消失。超微组织病理观察发现,患病对虾肝小管上皮细胞的细胞膜消融,细胞器解体,细胞核固化;其后细胞解体、脱落,甚至肝小管组织结构解体消融;肝胰腺、肠道、胃黏膜周围发现大量细菌,优势菌株为杆状菌且呈弧形,未发现病毒粒子的存在。从患病虾苗分离出2株优势菌(Lv-A和Lv-B),经人工浸染实验发现,Lv-A和Lv-B可致凡纳滨对虾PL7苗种出现与自然患病相同的玻璃化症状,其半致死浓度分别为1.62×10~3和5.38×10~3 CFU/mL,致病力强。根据16S rDNA和gyrB序列分析结果发现,Lv-A和Lv-B与溶藻弧菌、新喀里多尼亚弧菌和副溶血弧菌均有较高相似性。初步将该病命名为虾苗细菌性玻化症(shrimp postlarva bacterial vitrified syndrome,BVS)。药敏实验结果显示,Lv-A和Lv-B均对米诺环素、多西环素、萘啶酸等敏感,而对新霉素、吡哌酸、利福平等耐药。本研究为BVS的有效防控、保障对虾行业健康发展提供理论基础和技术支撑。 相似文献
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Thenmoli Vallipuram Sundarabarathy Udeni Edirisinghe & Chandraratne Mahinda Bandara Dematawewa 《Aquaculture Research》2005,36(2):196-201
This study was aimed to develop captive breeding and nurture the young of stonesucker (Garra ceylonensis, Bleeker), a small threatened freshwater fish species endemic to Sri Lanka. Breeding of stonesucker was possible under indoor conditions without hormonal stimulation. They were single spawners having a fecundity of 562±176 eggs per fish (total length of 7.9±0.6 cm) with an egg size of 770–1877 μm. Duration of development stages were, egg to hatchling 36–48 h, hatchling to postlarva stage 3–4 days, postlarva to juvenile stage 5–64 days and adult stage in 300–365 days at 26–28°C. Juveniles exhibited bottom dwelling habit in 70–75 days. Postlarva fed with formulated feed exhibited the highest growth (P<0.05) compared with live diets, Artemia and microworm (Anguillula sp.). Although the juveniles revealed a significantly high growth performance (P<0.05) with swine liver diet up to day 45 compared with formulated feed and combination of detritus and plankton, formulated feed exhibited an increase in growth from day 50. Therefore, formulated feed could be used for rearing of postlarva and juvenile stages without any live feeds. 相似文献
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Metupenaeus ensis larvae at different stages were exposed to a series of nitrite-N (nitrite as nitrogen) concentrations in static renewal toxicity tests. Larvae at zoea stage were the most susceptible, and postlarvae were the most tolerant to nitrite among the larvae tested. The 24 h LC50 s were 31.29, 16.05, 47.60 and 70.06 mg/L nitrite-N for third nauplius substage (N3). second zoea substage (Z2), second mysis stage (M2), and first postlarva substage (PL1), respectively, in 33 ppt seawater at a pH of 8.20 and a water temperature of 30 C. The 48 h LC50 for M2 and PL1 were 20.67 and 27.10 mg/L nitrite-N, respectively. The "threshold time" was 108 h, and the "incipient LC50 " for M. ensis PL1 was 7.06 mg/L nitrite-N. A "safe level" for rearing M. ensis larvae was estimated to be 0.71 mg/L nitrite-N in the hatchery. 相似文献
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Experiments were conducted with the larvae and early juveniles of three species of sturgeon to determine effects of diet and development on swimming and foraging behaviour as well as depth distribution in 100-L aquaria. About 500 hatchlings were placed in each tank with two or three replicates of three or six diet treatments, including live and dry feeds. Eight types of swimming or foraging activity were recorded with a lap-top event recorder and with fish counts in three depths of water. Analysis of variance showed live diets resulted in greater foraging activity in upper water horizons than most dry diets for Atlantic sturgeon, Acipenser oxyrhynchus Mitchill. Scouring, a foraging activity, differed among diet types in early juvenile lake sturgeon, A . fulvescens Rafinesque. Developmental effects included early peaks in the performance of swim-up for all species and swim near surface for two of three species. Postlarvae (post-yolk-sac larvae) of shovelnose, Scaphirhynchus platorhynchus (Rafinesque), and Atlantic sturgeon swam inverted, an apparent foraging tactic associated with elevated or air-water surfaces. Postlarvae maintained (lake sturgeon) or shifted to (other species) bottom swimming with increased scouring activity. Shovelnose early postlarvae occupied higher average water-column heights than lake or Atlantic sturgeon. Shovelnose (only species tested) postlarvae showed greater activity in upper water horizons at night. These results suggest a fundamental shift to benthic foraging during the postlarval phase, with shovelnose sturgeon continuing to forage in suprabenthic zones to a greater degree than the other two species. 相似文献
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L. J. LESTER 《Aquaculture Research》1988,19(3):243-251
Abstract. Full-sib families of Penaeus stylirostris Stimpson and Penaeus vannamei Boone were grown under controlled conditions in five experiments. Total length of shrimp larvae was measured at the following substages: protozoea one, mysis one and postlarva one. Analysis of variance showed that families differed significantly in size in all experiments at all substages tested. The average size possessed by a group of larvae early in development was significantly correlated with the size obtained in the later stages in P. siylirosiris , but not in P. vannamei . The component of variance in size due to family differences was determined and used to estimate heritabilities of size at the three larval substages in both species. Estimated heritabilities were higher for P. stylirostris than P. vannamei . In P. vannamei . the hcritability of size is greater for the protozoea and postlarval stages than the mysis stage. 相似文献
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Ekaterina E. Kovalenko Louis R. D''Abramo Cortney L. Ohs Randal K. Buddington 《Aquaculture (Amsterdam, Netherlands)》2002,210(1-4):385-395
A high moisture (63–71%), semi-purified microbound diet containing alginate was compared to newly hatched live Artemia nauplii as an exclusive diet for the culture of larval freshwater prawn Macrobrachium rosenbergii from 5th stage (weighted mean) through metamorphosis to postlarva. Two separate trials, representing larvae from different hatches, were conducted. Larvae were stocked at 50/l into cone-shaped vessels that contained 2 l of 12‰ seawater and were part of a temperature-controlled (28 °C) recirculating culture system. Larvae were manually fed either the live Artemia diet or the microbound diet exclusively, several times daily. After 14 days (23 days post-hatch (dph)), growth of larvae fed the microbound diet was 90% of that achieved for larvae fed newly hatched nauplii of Artemia. Survival of larvae fed the microbound diet was 77.3% and 73.3%, and was not significantly different from that of Artemia-fed larvae. Composed of readily available ingredients, the diet contains 46.2% crude protein and 37.4% lipid, is easy to prepare, and has good water stability. The diet is an economically practical alternative to the fluctuating cost, nutrient uncertainty, and labor associated with the use of Artemia nauplii hatched from cysts. The characteristics of the diet suggest good potential for successful use in the larviculture of other fish and crustacean species, in either the existing or a modified state. 相似文献
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Bharat Chandra Sahu Abhijit S. Mahapatra Lambodar Dey 《Journal Of Applied Aquaculture》2013,25(4):365-376
A nutrient budget was quantified for six polyculture ponds of giant freshwater prawn (Macrobrachium rosenbergii) and Indian major carps (Catla catla, Labeo rohita, and Cirrhinus mrigala). The initial stocking size of prawn postlarva was 16.50 ± 0.54 mm with a body weight of 0.05 ± 0.001 g. Body weight of major carps was 9.0 ± 0.89 g. The duration of culture was 280 days. Feed accounted for 82% of total nitrogen (N), 93% of total phosphorus (P), and 95% of organic carbon (OC) inputs. Harvest of prawn and carps recovered 44% N, 1% P, and 19% OC. N, P, and OC accumulated in sediment were 47%, 73%, and 69%, respectively. Nutrient load in the harvest water was 0.67 ± 0.21 kg inorganic N, 0.15 ± 0.01 kg P, and 7.72 ± 0.62 kg OC per ton of Indian major carps and prawn. 相似文献