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目前我国北方地区鲍养殖方式主要是底播增殖和筏式养殖,并已形成一定的规模。但当前养鲍存在突出问题就是鲍的生长速度慢,养成周期长,海上成活率低,极大影响养鲍的生产效益。一般情况下,鲍鱼人工养殖约需3年,海上养成成活率仅70%左右。我市鲍养殖业起步较早,发展较快,技术较为成熟,特别是筏式养鲍积累了一些经验,与其他地区相比,养成周期缩短半年左右,养成成活率提高10%以上,平均亩年效益达 40000多元。现就我们在生产中的实践经验,对影响的生长及成活的主要因素进行初步探讨。1 环境条件对鲍生长及成活的影响1… 相似文献
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莆田市鲍增养殖现状、问题与发展对策 总被引:1,自引:0,他引:1
莆田市1993年开展鲍工厂化育苗与养殖工作,养殖规模达到50万粒,年育苗种100万粒,由于工厂化养殖投资高,养殖周期长,生产单位出现亏损,鲍养殖生产随后滑坡。1998年在南日岛开展皱纹盘鲍海区筏式吊养技术,取得了83.53%高的成活率,从而又推动鲍养殖的发展。但从2000年至今,鲍养殖过程中出现大量死亡现象,有的成活率仅为25%,给养殖者带来严重的损失。作者对死亡的原因进行分析,并对今后的发展提出了一些设想。 相似文献
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杂交西氏鲍是日本优良养殖品种西氏鲍(厦门大学鲍遗传育种团队引进)和本土皱纹盘鲍杂交而来的品种,杂交受精率达到70%以上,养殖成活率比皱纹盘鲍提高20%,生长速度较快,杂种优势明显。 相似文献
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采用阴干加紫外线处理海水催产的方法,进行九孔鲍室内人工育苗研究,使用雌亲鲍1343粒,平均规格5.7cm,雄亲鲍117粒,平均规格5.8cm,共获得受精卵9500万粒,受精率91.5%,以塑料薄膜作为附着基质,共附着匍匐幼体607万粒。经过64~73d的附着期间的管理,剥离0.21~1.0cm稚鲍347万粒,成活率达57.2%,又经过98~102d的培育,获得规格1.0~2.5cm的鲍苗121.5万粒,平均成活率达35.0%。 相似文献
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杂交鲍(皱纹盘鲍大连群体与盘鲍日本群体杂交及其后代,以下同)是目前我国鲍养殖的主要种类.但由于多年来的自繁自育以及养殖生态环境恶化等原因,出现了养殖鲍病害频繁发生、生长缓慢、成活率低等现象.要解决存在的问题,必须改变以往的思路和方法,可以采取杂交鲍育苗和养成分别集中在不同海区,并采取种质优化,提供苗种培育的适宜的生态环境条件等措施,即通过采用选择育种、杂交育种和亲鲍优化培育等方法改良和优化种质.通过采用温和催产、理想藻种预先培养、控制光照强度和使用微生态制剂等方法满足其生理生态条件要求,以期达到杂交鲍苗种健康培育之目的. 相似文献
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绿盘鲍由于其在生长速率和成活率方面均优于皱纹盘鲍,大有取代皱纹盘鲍成为主要养殖对象的趋势。然而之前养殖户对绿盘鲍的接触较少,容易被蒙骗。同时育苗场也是各种乱象。 相似文献
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目前,在福建、广东等南方地区的鲍鱼养殖主要有陆上水池养殖与海区筏式养殖两种方式,养殖的主要品种为盘鲍和九孔鲍。海区筏式养鲍常常受到台风、赤潮、附着生物等诸多因素的影响,增加了养殖风险,成活率仅50%~60%。陆上养殖虽然养殖成活率可达70%-80%,但是养殖成本太高,而且养殖周期要比海区长。因此我们提出了鲍鱼海区与陆上轮养的养殖模式。经过几年的实践,取得很好的效果。 相似文献
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探讨低温(4 ℃)条件下的厚壳贻贝早期幼虫保存可能性,同时调查了不同培育密度对低温保存的影响。在正常条件下,继续培育低温保存后的幼虫,并调查其存活率和生长的变化。 结果表明,在低温保存后,早期幼虫存活率较高,超过95%;厚壳贻贝早期幼虫的壳长和壳高出现显著性的增长。不同培育组间,培育密度对厚壳贻贝早期幼虫的存活和生长影响不同,表明密度是幼虫低温保存的一个重要因素。在正常培育条件下,低温保存后的幼虫,3周后其存活率明显低于对照组,但仍超过50%,且其生长速度明显高于对照组。因此,低温培育是保存厚壳贻贝早期幼虫的有效方法,可用于今后贝类幼虫生物学实验和人工育苗技术的改善研究。 相似文献
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马氏珠母贝浮游幼虫不同阶段的选择效应 总被引:2,自引:0,他引:2
研究了在马氏珠母贝浮游幼虫期的选择效应,分别在担轮幼虫期和眼点幼虫期对幼虫进行了选育,以期通过在浮游幼虫期的选择来降低良种选育中的工作量和加快选育进程。试验结果表明,1)担轮幼虫早期上浮组比后期上浮组在D型幼虫孵化率上提高了5.1%,D型幼虫畸形率降低了10.1%;2)担轮幼虫早期上浮组在第17d的大小和成活率以及稚贝出池时的大小和育成率都显著地(P0.05)高于担轮幼虫后期上浮组;3)眼点幼虫早期附着组在稚贝出池时的大小和育成率上都显著地(P0.05)高于眼点幼虫后期附着组。研究结果表明对马氏珠母贝在幼虫浮游期的选择具有显著的效应(P0.05)。 相似文献
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营养强化的轮虫、卤虫对牙鲆仔鱼的成活、生长及体脂肪酸组成的影响 总被引:12,自引:2,他引:12
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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观察研究了10个盐度梯度(7、12、17、22、27、32、37、42、47和52)对条纹锯鮨(Centropristis striata)仔鱼的活力、开口和摄食情况的影响,记录分析其在不同盐度条件下不投饵存活系数、开口率、摄食率及摄食强度等指标.结果显示,盐度对条纹锯鮨仔鱼的活力、摄食及存活有明显影响,其存活和摄食的适宜盐度范围为12-37,最适盐度范围为27-32.盐度低于12时,仔鱼存活率、开口率和摄食强度随盐度的降低而降低,盐度高于37时,仔鱼存活率、开口率及摄食强度则随盐度的升高而降低.不同盐度条件下,条纹锯鮨仔鱼SAI值的波动范围为0.034-6.401,盐度为12-37的实验组与7、42、47、52实验组的SAI值存在显著性差异(P<0.05),盐度为32时,仔鱼的SAI 值最大,为6.041,SAI值与盐度之间符合三次曲线函数关系,其表达式为y=-5.894+1.155x-0.034x2+0.000x3,R2 =0.895,其中,y代表SAI,x代表盐度.盐度为7、42、47和52时,仔鱼的存活率均低于50%,盐度为52、47时,仔鱼在第3、4天存活率分别降为0.盐度为22、27、32时,培育至第5天,仔鱼的存活率均在80%以上.盐度在17-37范围内,仔鱼开口率为60%-85%,且仔鱼均能较好摄食,盐度为32时,仔鱼开口率达到最大值,为85%,仔鱼摄食亦达到最佳状态,摄食率为85%,8日龄仔鱼摄食强度为5.45个轮虫/尾. 相似文献
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为了深入了解光照对红条鞭腕虾(Lysmata vittata)亲虾抱卵情况的影响,本研究通过将正常光照组(12L∶12D)亲虾的抱卵率与全暗(黑)组进行对比,发现正常光照组红条鞭腕虾亲虾抱卵率为(95.8±3.6)%,而全暗(黑)组的抱卵率为0,正常光照组亲虾的抱卵率显著高于全暗(黑)组(P0.05),表明适宜的光照强度对红条鞭腕虾亲虾抱卵行为起到促进作用。本研究还对比分析了投喂不同生物饵料对红条鞭腕虾溞状幼体成活率和生长发育周期的影响。结果发现,投喂丰年虫(Artemia nauplii)和蒙古裸腹溞(Moina mongolica Daday)混合组的溞状幼体成活率为(38.3±2.3)%,幼体经过25~29 d全部发育成仔虾;而单一投喂丰年虫组的溞状幼体成活率为(26.8±4.9)%,幼体经过37~41 d全部发育成仔虾;混合组的溞状幼体成活率显著高于单一组(P0.05),且其幼体的生长周期也明显短于单一组,表明投喂丰年虫和蒙古裸腹溞混合饵料比只投喂丰年虫饵料更有利于幼体的存活和发育。此外,本研究还观察和详细描述了红条鞭腕幼体发育过程的形态和结构变化特征,并将它分为溞状幼体1~9期等9个不同时期,幼苗经过9期溞状幼体期后通过蜕皮最终变态为红条鞭腕虾仔虾。本研究对丰富鞭腕虾属虾类的生殖生物学理论和开展其人工繁育研究具有重要的指导意义。 相似文献
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Hirofumi Furuita Tatsuya Unuma Kazuharu Nomura Hideki Tanaka Tsuyoshi Sugita & Takeshi Yamamoto 《Aquaculture Research》2009,40(11):1270-1278
This paper describes the relationship between the egg vitamin concentrations and the egg quality in the Japanese eel Anguilla japonica . No notable relation was found between any vitamin and the fertilization rate. Hatching and survival rates of larvae, however, significantly increased with an elevated level of egg vitamin C (VC). In contrast to VC, the relation between vitamins E (VE) and A (VA) concentrations and survival rate showed a clear peak, with a reduced survival rate at both higher and lower vitamin concentrations. The ratio of VE to lipid or highly unsaturated fatty acid (HUFA) in eggs positively correlated with hatching and survival rates of larvae. High-quality (HQ) eggs were determined as eggs that produced larvae having a survival rate higher than 80% at 8 days post hatch, and low-quality (LQ) eggs were determined as eggs that did not hatch. The level of VC of HQ was significantly higher than LQ. The results of this study suggest that HQ eggs, which produce larvae having a high survival rate, must have high levels of VC and VE/HUFA ratio and contain optimum levels of VA and VE in Japanese eel. 相似文献
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After 1984 the major spawning of the Japanese sardine, Sardinops melanostictus, has been observed to occur in the offshore waters, where the survival of early-stage larvae (4–10 mm in length) is questionable. The main objective of this study is to estimate the growth and survival rates of the early-stage larval cohort in the offshore side of the Kuroshio Current. A radar-reflecting buoy with a surface drogue was launched to tag a patch of larvae, and the patch was traced for 3 days in March 1991. The survival rate of the early-stage larval cohort was calculated from the change in density during the survey. The range of the instantaneous mortality rate was from 0.83 to 1.11 day, a survival rate of32-44%day-1.The mean density of the smaller larvae (4–6 mm in length) decreased more rapidly than that of the larger larvae (6–10 mm in length) during the sampling period. The survival rate of the first-feeding larvae in the offshore region seemed to be lower than that of the post-flrst-feeding larvae. However, the growth rates of the first-feeding larvae's survivors in the region were higher than those of the post-first-feeding larvae's survivors. The first-feeding larvae in the offshore region seemed to survive when the growth rate of the larvae was high. 相似文献
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Jorge Palma Dominique P Bureau Miguel Correia & José P Andrade 《Aquaculture Research》2009,40(13):1468-1473
This investigation examined the effects of temperature, density and early weaning on the survival and growth of Palaemonetes varians larvae. Survival of larvae raised at 17.5 °C was not significantly different (average + standard deviation) (94 ± 5%) from the survival of those raised at 19.5 °C (95 ± 5%) and at 21.5 °C (94 ± 4%). However, the duration of the larval stage was significantly longer for shrimp reared at 17.5 °C (17.3 ± 0.8 days) compared with shrimp reared at 19.5 °C (14.3 ± 0.7 days) and at 21.5 °C (11.3 ± 0.6 days). No significant differences ( P >0.05) were found in the survival rate, final weight and length of larvae reared at the densities of 5, 10, 20 and 50 larvae L−1 . The survival of P. varians larvae fed solely on Artemia was significantly higher ( P <0.05) than larvae weaned with an artificial practical diet from Zoea II stage (94 ± 4% and 82 ± 1%, respectively, for Artemia and artificial diet-fed larvae), but no significant differences ( P >0.05) were observed in the final larval weight or length between these two treatments. The survival and growth of the larvae fed with the practical diet tested is a promising step ahead in the development of the culture of this species as it eliminates both the need for Artemia throughout all larval stages, and the need for more expensive artificial diets. 相似文献