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971.
为了探讨贻贝人工育苗的规模、数量、茬次等问题,本文对采卵的规律进行了研究。通过在不同季节和时期用变温刺激法来诱导排卵试验,认为在春季应用升温为主的常规综合刺激法,其排卵宁可达到60%以上;在秋季应以降温为主的变温刺激法,排卵率可达到40-60%。此外,文中对不同年龄的亲贝所排放生殖细胞的雌雄比例和采卵量等问题进行了讨论。  相似文献   
972.
In this study, a non‐programmable freezing technique has been developed with the strip spawned blue mussel (Mytilus galloprovincialis) sperm. The key parameters optimized including (1) cryoprotectant agents (CPAs); (2) cooling temperature; (3) thawing temperature; (4) sugar and amino acid supplementation and (5) sperm to egg ratio. The fertilization rate and/or integrity of plasma membrane and acrosome were used as sperm quality assessment indicators. The highest post‐thaw sperm fertilization rate of 95% was achieved, when sperm were cryopreservated in 8% dimethyl sulfoxide at 7.8 cm above the liquid nitrogen surface and thawed in a 60°C seawater bath. The addition of glucose, sucrose or trehalose in dimethyl sulfoxide did not, whereas 0.8% glycine did significantly improve the post‐thaw sperm fertilization rates. The fluorescent evaluation has demonstrated that the addition of glycine significantly improved the post‐thaw sperm acrosome integrity, revealing a positive role of glycine in the improvement of post‐thaw sperm quality in blue mussels.  相似文献   
973.
Live, attenuated Vibrio anguillarum strains can serve as vectors for the delivery of heterologous antigens for development of multivalent recombinant vaccines. Based on the outer membrane anchoring elements of V. anguillarum , we have previously constructed several efficient surface display systems Lpp-Omporf1, Lpp-OmpU, Lpp-Omp26La, Wza-Omporf1, Wza-OmpU and Wza-Omp26La. In this study, with these constructed surface display systems, a putative antigen protein EseB from pathogenic Edwardsiella tarda was successfully expressed on the surface of an attenuated V. anguillarum strain to get multivalent vaccine candidates. Further immune protection evaluation in zebra fish ( Danio rerio ) demonstrated that the V. anguillarum EseB-display strain AV/pW-26La-B could trigger full protection against V. anguillarum infection and early protection against E. tarda infection in the immunized fish. These results suggest that surface display of heterologous protective antigens in attenuated V. anguillarum could be used as a tool to develop potential V. anguillarum vector vaccine.  相似文献   
974.
日本对虾越冬亲虾性腺促熟及工厂化育苗技术研究   总被引:1,自引:0,他引:1  
1997、1998年利用越冬亲虾进行性腺促熟,用镊烫法切除眼柄,促进亲虾发育。结果:两年共培育亲虾雌虾8204尾。雄虾5683尾,获交尾虾5360尾。交尾率为71.81%。每年两批育苗,共利用水体1720m~3,育出0.7~1.1cm的虾苗12450万尾,平均单位水体出苗量为7.24万尾/m~3,效益显著。  相似文献   
975.
2004年和2005年分别对江苏省沿海滩涂4个具有代表性的文蛤重点增养殖区的环境因子进行了连续调查、监测和研究,主要分析测试了以下3个对文蛤生存影响较为重要的环境因子:底泥中的硫化物(S2-)、底泥渗水中的总氨氮(NH4-N)和底泥渗水中的化学需氧量(COD)。结果表明:S2-季节性变化明显,地点上随监测站位不同有显著差异;NH4-N夏季较高,其它时段基本无变化,均值远远高于上覆水体;COD含量除受气温影响外,还显著受到人类生产生活(如排污等)的影响。另外,2005年较2004年部分监测站位养殖环境有恶化趋势。  相似文献   
976.
Infectious hypodermal and haematopoietic necrosis virus (IHHNV) and white spot syndrome virus (WSSV) are two widespread shrimp viruses. The interference of IHHNV on WSSV was the first reported case of viral interference that involved crustacean viruses and has been subsequently confirmed. However, the mechanisms underlying the induction of WSSV resistance through IHHNV infection are practically unknown. In this study, the interference mechanisms between IHHNV and WSSV were studied using a competitive ELISA. The binding of WSSV and IHHNV to cellular membrane of Litopenaeus vannamei was examined. The results suggested that there existed a mutual competition between IHHNV and WSSV for binding to receptors present on cellular membrane of L. vannamei and that the inhibitory effects of WSSV towards IHHNV were more distinct than those of IHHNV towards WSSV.  相似文献   
977.
The goal of this experiment was to examine the effects of different light qualities (red, white, blue) and cycles (12L:12D, 8L:16D, 4L:20D, 0L:24D, 16L:8D) on the survival, growth, metabolism and antioxidant defence system of Haliotis discus hannai Ino. Under red and white light at 4L:20D, the body weight‐specific growth rate of abalones was significantly higher than that of the 0L:24D group (< 0.05). At 16L:8D, succinate dehydrogenase activity decreased and lactate dehydrogenase and alanine aminotransferase activity and the lactic acid content significantly rose (< 0.05) in the red and white light groups. Under blue light, reactive oxygen species and malondialdehyde content for each light cycle were significantly higher than those of the red and white groups (< 0.05). Under blue, white and red light, total antioxidant capacity (T‐AOC), superoxide dismutase (SOD) activity, glutathione peroxidase (GPX) activity and reduced glutathione (GSH) content gradually rose with increased duration of light exposure. Under red light, significant differences in these parameters were detected between the 4L:20D and 16L:8D groups (< 0.05). Under blue and white light at 16L:8D, values of T‐AOC, SOD, GPX activity and GSH content were significantly lower than those of the 12L:12D group (< 0.05). Overall, these results indicate that red light at light cycles of 4L:20D and 8L:16D is optimal for the culture and production of H. discus hannai, as these conditions promoted food intake, growth and health maintenance as well as normal physiological metabolism of the organism.  相似文献   
978.
本文阐述了养鳟业的经济意义和价值,并从养鳟用水和生产方式、苗种生产、食用鱼养成、养鳟饲料、海水养鳟,疾病防治等方面总结了养鳟基本技术,同时对我国养鳟历史作了回顾,提出了我国养鳟业的发展前景。  相似文献   
979.
高寒鲤染色体核型分析   总被引:3,自引:2,他引:3  
采用植物血球凝集素(PHA)体内注射,肾组织细胞短期培养,常规空气干燥法制备了高寒鲤染色体,核型分析结果是:高寒鲤染色体的核型公式为2n=100=28m+28sm+44stt,染色体臂数NF=156。  相似文献   
980.
渤海秋汛对虾数量预报方法的研究   总被引:2,自引:0,他引:2  
渤海秋汛对虾的数量预报,是我国渔业预报中比较成功的报例之一。本文简述了此项预报工作的发展过程,介绍取得预报指标——相对资源量的原则和方法、加权系数的推算以及对各种回归方程的预报效果的检验结果,提出了针对不同资源水平的预报计算方法。此外,还对有争议的预报中的渔捞努力量因素问题进行了讨论。  相似文献   
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