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Allograft and xenograft mantle transplantations were studied in three species of freshwater pearl mussels, Hyriopsis (Limnoscapha) myersiana, H. (L.) desowitzi and Chamberlainia hainesiana, by transplanting foreign mantle tissue into the mantle tissue of a host mantle. The pearl sac is completely formed within 15 days after an allograft. After a xenograft from a C. hainesiana donor into a H. (L.) myersiana recipient, it took 13 days, and in the opposite case it took 15 days. For a H. (L.) desowitzi donor, it took 21 days in a C. hainesiana recipient and 27 days in a H. (L.) myersiana recipient. When the recipient was H. (L.) desowitzi, no pearl sac was observed after xenografts from either of the other two mussel species. Allografts of C. hainesiana and H. (L.) myersiana yielded the highest success rate of forming pearl sacs (96 and 97% respectively). Xenografts from a C. hainesiana donor into an H. (L.) myersiana recipient yielded 94%, and the opposite case yielded 90%. The first completed pearl layer was found for xenotransplantation into a C. hainesiana recipient from an H. (L.) myersiana donor at 126 days after transplantation. 相似文献
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2004年,我们在利津县大力推广小型蓄水水库南美白对虾养殖技术,取得了较好的经济效益和社会效益。其中,在西冯水库120亩库区养殖南美白对虾的亩产260kg,亩效益2583元,现将其养殖实例总结如下:一、水库条件西冯水库建于1996年,位于引黄干渠旁,东西走向,水面面积120亩,长宽比2:1,平均有效 相似文献
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为充分利用水库的饵料鱼资源,提高水库水域的生产潜力,增加养殖收入,近几年,水库养殖鳜鱼在鹰潭市得到迅速发展,面积达到2万亩,经济效益非常显著.笔者通过多年的鳜鱼养殖技术推广,总结积累了一些水库养殖鳜鱼的相关技术,供养殖同仁参考. 相似文献
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1. Two experiments were carried out in a Scottish river to test the effects of electrofishing on endangered freshwater pearl mussels (Margaritifera margaritifera). 2. In the first experiment, two areas of mussel bed were marked out as treatment and control sites and the former was electrofished using standard equipment. The mussels were examined 10 min, 24 h and 35 days after treatment and their shell valve closure responses, burrowing capabilities and gravidities were recorded as signs of normal ‘functioning’. 3. In the second experiment, individual mussels were marked as treatments and controls and the former were electrofished. These mussels were examined as before. 4. No mortalities occurred and no significant differences in ‘functioning’ between treatments and controls were observed in either experiment. 5. Since no measurable treatment effect could be demonstrated, it appears that electrofishing did not adversely affect the short‐term survival of M. margaritifera. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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随着国家基本农田保护政策的实施,土地资源紧张的问题越发显得更加突出,很大程度上制约着罗非鱼产业化进程。为缓解上述问题以及顺应市场发展的需要,我们于2003年开始发动个别养殖户承包(承租)一些山塘、小型水库,并本着优质、生态、健康的原则实施精养试验,对清塘消毒、种苗品 相似文献
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目前,南方各省市河蟹的养殖方式主要是:池塘养蟹、湖泊网围养蟹、稻田养蟹、小型湖泊和小型水库养蟹。黑龙江省地处高寒地带,南方比较成熟的技术在该省不能完全适用,需要根据高寒地区的生态环境特点,结合河蟹不同品系的生活习性,研究出一套崭新的养殖技术。1999年开始,我们在高寒地区大水面进行河蟹养殖技术的研究试验,通过三年的摸索,在河蟹品系选择、放养、防逃、捕捞、病害防治、远距离运输、养殖模式等方面积累了一定经验,为在高寒地区进行河蟹大规模产业化生产奠定了基础。 相似文献
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黄颡,又名黄腊丁、嘎鱼,是一种小型淡水经济鱼类。属于杂食性,具有较强适应性,对水质要求不高,易于引种驯化,因其营养价值高而愈来愈受到广大消费者青睐,也是改善养殖品种结构的一种适合食用、垂钓的优良品种。我们在1999年~2001年连续进行了小池塘主养试验,普遍取得了良好结果,现将主要技术介绍如下:一、池塘条件选择面积2亩~10亩的零散小池塘,要求有充足的水源,水质符合养殖用水标准。池塘进排水方便,池底平坦,能保证1.5m水深,并以每5亩左右配备一台2.0kW增氧机为宜。二、准备工作在投放苗种前,新… 相似文献
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<正> 鲈鱼隶属鲈形目、常鲈鱼亚科,广盐性,是我国沿海重要的海水养殖鱼类之一。鲈鱼苗种来源于自然海区,资源丰富,鲈鱼具有生长快、适应性广、抗病力强、肉质鲜美等特点,深受人们欢迎。为探讨其高产养殖技术,增加经济效益,从1999年开始,我们指导养殖户在洋河水库从事网箱高密度养殖鲈鱼试验。现将养殖技术介绍如下: 相似文献
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为了筛选优质的珍珠蚌插片组合,探究不同种类珍珠蚌相互插片后生长性状间的差异和相关性,以及各组合无核珍珠成珠率和大小的差异,利用三角帆蚌(S)、池蝶蚌(C)和褶纹冠蚌(Z)分别作为供片蚌和育珠蚌,获得9个育珠蚌组合,测量各育珠组合的体质量、壳长、壳高和壳宽,比较9个育珠蚌组合及3个未插片的三角帆蚌、池蝶蚌和褶纹冠蚌对照组在1年后生长性状的差异,对各生长性状相关性进行分析。测量每个育珠蚌所产无核珍珠的数量和大小,计算成珠率和圆度,分析不同组合之间无核珍珠的差异。结果显示,无核育珠手术影响珍珠蚌的生长性能,以三角帆蚌和池蝶蚌为育珠蚌的组合生长性状均优于对照组,S-S育珠组合在以三角帆蚌为育珠蚌组合内生长最优,SC和C-C育珠组合在以池蝶蚌为育珠蚌组合中生长最优,而以褶纹冠蚌为育珠蚌的组合插片后生长性状指标均小于对照组。其中除了池蝶蚌同种插片组合(C-C育珠组合)外,其余各育珠组合壳长与体质量间相关系数均高于其他生长性状间相关系数,C-C育珠组合壳宽与体质量相关系数最大;三角帆蚌和池蝶蚌之间的插片组合(S-S、C-S、S-C和C-C育珠组合)及褶纹冠蚌同种插片组合(Z-Z育珠组合)成珠率较高(... 相似文献