...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>ICES Journal of Marine Science >Effects of water quality and stocking density on growth performance of juvenile cod (Gadus morhua L.)
【24h】

Effects of water quality and stocking density on growth performance of juvenile cod (Gadus morhua L.)

机译：水质和放养密度对鳕鱼生长性能的影响

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

In a 5-month experiment where groups of juvenile cod were reared in a flow-through system at low density (Group 1) and in a recirculating system at low (Group 2) and high densities (Group 3), the recirculated water had negative effects on growth rate, nutritional condition, and mortality. After the first month, mean weight was significantly larger in Group 1 than in the other two groups. The effect of stocking density on mean weight was not significant until the end of the experiment, when densities were 9.0 and 48.3 kg m~(-3) in Groups 2 and 3, respectively. Initial mean weight of fish was 37.3 g and at the termination of the experiment mean weights were 225.2, 181.8, and 167.9 g in Groups 1, 2, and 3, respectively. After 5 months, mean condition factors were 1.074, 0.965, and 0.946, mean liver indices 9.5, 9.0, and 7.6, and mean mortalities over the course of the experiment were 1.0%, 5.1%, and 2.4% in Groups 1, 2, and 3, respectively. Water temperature (10.4-10.6℃), pH (7.2—7.4) and oxygen concentration (8—10 mg l~(-1)) were similar among groups. Concentration of total ammonia nitrogen (TAN) was similar among groups for the first half of the experiment (0.3—0.4), but during the last month it was 0.6, 1.3, and 1.5 mg l~(-1) in Groups 1, 2, and 3, respectively. There was a negative correlation (r~2 = 0.48, n = 36) between relative growth rate and TAN, suggesting that ammonia may have been a limiting factor in the recirculating system. The apparent threshold limit of TAN for reduced growth was approximately 1 mg l~(-1).
机译：在一个为期5个月的实验中，在低密度（流通组）（第1组）和低密度（第2组）和高密度（第3组）的循环系统中饲养了幼鳕鱼群，再循环水的水量为负值。对生长速度，营养状况和死亡率的影响。第一个月后，第一组的平均体重明显高于其他两组。直到实验结束，放养密度对平均体重的影响才显着，当第2组和第3组的密度分别为9.0和48.3 kg m〜（-3）时。第1、2和3组中鱼的初始平均重量为37.3 g，在实验结束时分别为225.2、181.8和167.9 g。在第5、2组中，在5个月后，平均条件因子分别为1.074、0.965和0.946，平均肝脏指数9.5、9.0和7.6，并且在实验过程中的平均死亡率分别为1.0％，5.1％和2.4％。和3。各组之间的水温（10.4-10.6℃），pH（7.2-7.4）和氧浓度（8-10 mg l〜（-1））相似。实验上半年各组的总氨氮（TAN）浓度相似（0.3-0.4），但在最后一个月，第1、2组分别为0.6、1.3和1.5 mg l〜（-1）。 ，和3。相对生长速率与TAN之间存在负相关关系（r〜2 = 0.48，n = 36），表明氨可能是再循环系统中的限制因素。减少生长的TAN的表观阈限约为1 mg l〜（-1）。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号