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<正> 牡蛎,又名蚝、海蛎子,是我国重要的海水养殖贝类,主要养殖品种有褶牡蛎、近江牡蛎两种.养殖业集中于福建、广东、台湾三省;浙江也有养殖,数量不多.养殖面积约40万亩,年产量约80万担.1973年发展贻贝养殖之前,其面积与产量在我国海水养殖贝类中始终占第一位,目前产量虽已低于贻贝(约500万担),但其养殖面积仍占首位. 相似文献
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我国的海水养殖面积和产量均居世界首位。据统计,2002年我国海水养殖产量达1212.84万吨,海水养殖面积134.475万公顷。其中滩涂贝类产量约占我国海水养殖总产量的19%。本文所指滩涂贝类品种主要为缢蛏、菲律宾蛤仔、文蛤、青蛤、蚶类、牡蛎等。池塘养殖滩涂贝类,就是利用沿海滩涂的虾塘、围垦,或筑堤围塘,进行蓄水养殖。其优点是投资少,风险小,效益高,设施和操作简单,受不利环境的影响小。本文着重介绍利用池塘进行缢蛏、蛤类和蚶类的健康养殖技术。 相似文献
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我国的海水养殖始于20世纪50、60年代,近50年来,走过了藻类养殖、双壳贝类养殖、甲壳类养殖、鱼类养殖的发展过程,目前,海水养殖已成为我国渔业的一个重要组成部分。在称为“海洋世纪”的21世纪,展示在我们面前的将是一个以鱿类养殖为发展重点的海水养殖业,然而,随着海水养殖业的逐步发展,病害问题日益突出,制约着海水养殖业的进一步发展,能否有效地控制病害是关系到海水养殖健康发展的关键之一。本文就此提出了些看法和观点。 相似文献
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我国的海水养殖业与可持续发展的对策 总被引:3,自引:0,他引:3
一、海水养殖业的现状我国海水养殖业在解放前几乎是空白的 ,50年代主要是养殖海带和牡蛎、蛏等一些贝类 ,全国产量很少 ,到1960年全国海水养殖产量仅21.16万吨。但是 ,90年代起海水养殖迅速发展 ,1990年全国海水养殖产量284.22万吨 ,到1995年海水养殖产量达到721.92万吨 ,五年间增长2.54倍 ,以后逐年有所提高。到1998年海水养殖产量达到860.04万吨 ,养殖面积达到1004.41公顷。在海水养殖产量中贝类的产量达到700.25万吨 ,占总产量的81.42 % ,藻类产量102.42万吨 ,… 相似文献
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江苏经济贝类养殖概况与对策研究 总被引:2,自引:0,他引:2
江苏沿海多为滩涂地带,拥有953.9公里的海岸线,总面积65.8万公顷。其中,潮上带面积26.6万多公顷,潮问带26.5万多公顷,岸外沙洲面积12万多公顷。海岸中部,仍在以每年1000多公顷的速度向海淤进,对于人多地少的江苏更具有特别重要的意义。全省已开发的近10万公顷海水养殖面积中,贝类养殖面积和养殖产量分别占海水养殖总面积和总产量的76.4%和91.4%,使沿海滩涂“变废为宝”,促进了江苏沿海经济的发展。本文就江苏经济贝类的养殖情况进行了归纳。 相似文献
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国内外养殖贝类质量安全管理比对及我国贝类质量安全管理探讨分析 总被引:3,自引:0,他引:3
贝类增养殖在我国水产养殖中占有非常重要的地位.2009年我国海水贝类养殖面积达到115.4万公顷,贝类产量1053.05万吨,占海水养殖总量的74.9%.然而,双壳贝类属于滤食性生物,在滤食饵料生物的同时,也会将水中的有害物质摄入体内.日益加剧的环境污染直接影响到养殖贝类的食用安全.近年来,食用贝类造成的中毒事件也时有发生.贝类出口贸易同样受到制约,1997年起欧盟禁止进口我国的贝类和贝类产品,我国的鲜活双壳贝类对美国出口也一直没有打开,十多年的封关对我国的贝类产业造成重大影响. 相似文献
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Two experiments were conducted to investigate the efficacy of three androgens applied through immersion treatments on the sex ratio of Nile tilapia (Oreochromis niloticus L.) fry. In experiment 1, 14 days post‐hatching (DPH) larvae were exposed to a single immersion treatment in 17α‐methyltestosterone (MT), 17α‐methyldihydrotestosterone (MDHT) or 17α‐ethynyltestosterone (ET) at 200, 600 and 1800 μg L?1 over 4 h (130 larvae per treatment). In experiment 2, Nile tilapia larvae were exposed to the higher androgen concentration (1800 μg L?1) applied as either a single immersion (14 DPH) or double immersion (10 and 14 DPH) over 4 h (125 larvae per treatment). Change in sex proportion within each experiment as well as between experiments was analysed by the chi‐square test. In experiment 1, MT, MDHT and ET were equally effective in significantly increasing the proportion of males when applied at 1800 μg L?1 (86.0%, 90.0% and 86.7% respectively). At 200 μg L?1 none of the androgens altered sex ratio. At 600 μg L?1, only MDHT slightly, but significantly skewed the sex ratio towards males (73.0%). In experiment 2, a single immersion treatment at 14 DPH (1800 μg L?1) significantly increased the proportion of males, but at this time the response was significantly hormone dependent (MDHT, 100.0%; MT, 91.6%; ET, 76.9%). When compared with a single immersion, two‐immersion treatments significantly increased the proportion of males in the MT‐treated group (from 91.6% to 98.3%), decreased the proportion of males in the MDHT group (from 100.0% to 93.4%) and had no significant effect the ET‐treated group (change from 76.9% to 82.5%). The overall comparison of the sex ratio among same treatments from different experiments (a single immersion in 1800 μg L?1) was not significantly different. 相似文献
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本文通过对比试验的方法,定量地研究了影响河蟹早熟的5种因子,通过控制5种因子,使河蟹性早熟的比例控制在10%以内,取得了较理想的经济效益,同时,分析探讨了影响河蟹性早熟的内、外因子。 相似文献
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《Journal Of Applied Aquaculture》2013,25(2):27-38
Channel catfish, Ictalurus punctatus, adults were stocked at 3,705 fish/ha in twelve 0.04-ha earthen ponds and fed to satiation either once or twice daily with diets containing either 32 or 38% protein for 170 days. Experimental diets with the appropriate levels of essential amino acids, vitamins, and minerals were formulated by a commercial feed mill. There were no significant differences (P > 0.05) in growth and body composition of channel catfish when analyzed by protein level, feeding frequency, or their interaction. Average individual fish weight at harvest was 1,600 g. Average net production was 3,125 kg/ha. Dry-weight percentages of protein, fat, and ash in the carcass were 55.5, 38.1, and 6.7%, respectively, and in the waste (head, skin, and viscera) were 40.5, 43.2. and 12.5%. respectively. Third-year channel catfish may be able to utilize a diet with lower (<32%) protein levels and a reduced energy: protein ratio. 相似文献
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