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牙鲆年龄和生长的研究 总被引:6,自引:1,他引:6
本文根据1980—1986年间连续逐月牙鲆生物学测定和耳石观察资料,确认其年轮形成期在3—5月,主要在4月。经标准von Bertalanffy生长方程拟合,鱼体体长(mm)年间生长规律为: ♀:L_t=800.10[1-e~(-0.2323(t-0.0254))] (?):L_t=690.62[1-e~(-0.2557(t+0.1211))]依体长与体重间相关关系计算渐近体重和最大生长速度,雌鱼分别为8370.43g和865g/a;雄鱼分别为4867.15g和554g/a。对低龄鱼(0—Ⅲ)生长特征模拟结果表明,雄鱼体长生长的季节变动幅度(C=1.07,k=0.5925)明显大于雌鱼;当年生雄鱼在7—9月的生长速度为年内最大。 相似文献
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假晴东方鲀人工育苗获得41.8mm种苗351000尾,每立方水体出 苗860尾。越冬成活率91.6%,增重率61.8%。利用室内水泥池及养虾土池 养成商品鱼,分别获得1969 g/m3和 208 kg/亩的收成。 相似文献
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假晴东方Tun人工育苗获得41.8mm种苗351000尾,每立方水体出苗860尾。越冬成活率91.6%,增重率61.8%。利用室内水泥池及养虾土池养成商品鱼,分别获得1969g/m^3和308kg/亩的收成。 相似文献
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本文介绍利用深井海水越冬并利用室内水泥池和室外土池两种养成情况。1 人工越冬试验本试验利用深井海水进行假晴东方越冬获得成功。越冬于1991年12月5日~1992年5月10日,全部过渡到自然海水温度为止,历时160d左右。入池幼鱼2600尾,越冬结束成活2381尾,成活率91.6%。1.1 条件越冬场址在莱州湾,利用闲置的对虾育苗室。越冬池为长方形水泥池,面积分60m2,45m2,35m2三种规格,池深1.3~1.4m。越冬用水全部取自地下深井海水,井水温度长年稳定在15.8~17.2℃,盐度20左右。提水设备为两台2.2kW潜水泵,最大流量为30m3/h。1.2 管理越冬期根据气… 相似文献
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INTRODUCTIONTriploidyinductionandgynogeneticdiploidinductionasmainpartsofchromosomalmanipula tionhavebeenplayingmoreandmoreimportantrolesinmodernfishbreeding .Mosttriploidfisharesterileandtheirreducedgonadaldevelopmentresultsinimprovementofgrowthratea… 相似文献
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南黄海浅层地震调查及其地质意义 总被引:2,自引:3,他引:2
利用声波研究浅层沉积构造,已被许多地质学家在海洋地质、工程地质的调查和研究中广泛采用.浅层剖面仪是连续声波法的主要设备,它可以将人工激发声波从地层界面反射到水面的时间和强度,电击在记录纸上作出时间剖面.由于仪器分辨率较高,这种时间剖面可以形象地反应出岩层内的许多细微构造.认真分析、对比这些剖面记录,可以对测区的浅层构造形态、沉积特点等作详细的了解和研究. 相似文献
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STUDY ON EMBRYONIC DEVELOPMENT AND EARLY GROWTH OF TRIPLOID AND GYNOGENETIC DIPLOID LEFI—EYED FLOUNDER, PARALICHTHYS OLIVACEUS (T. et S. ) 总被引:1,自引:0,他引:1
The early effects of chromosomal manipulation of eggs and sperm on the yields of trip-loid and gynogenefic diploid larvae of Paralichthys olivaceus were investigated. Triploidy was achieved by cold shocking fen.ilized eggs at 0 - 2℃ for 45 minutes duration 5 minutes after fen.ilization, and the in-duced triploidy rates were 31.2% - 50% and the relative hatching rates were 53.3% - 99%. Gynnge-aetic diploids were obtained when eggs were inseminated with irradiated sperm and cold shocked at 0 -2℃ for 45 minutes duration 5 minutes after fertihzation. The induced gynogenetic diploid rates and the relative hatching rates were 94 % - 96 % and 48.5 % - 68.5 % respectively. The embryonic development of the triploid experimental group and of the gynogenetic diploid experimental group was delayed at first compared with the control group. But from the gastrula stage, it was not delayed anymore. There were no significant differences in the growth of the triploid experimental group larvae and the control group larvae, and in the growth of the gynogenetic diploid experimental group larvae and the control group larvae ac-cording to Student‘s t-test (α = 0.05). The relationship between the early growth of the triploid experi-mental group larvae and that of gynogenetic diploid experimental group larvae was also studied. 相似文献