盐度对真鲷受精卵发育及仔稚鱼生长的影响

来源 :中国水产科学 | 被引量 : 0次 | 上传用户:shwjdbr
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
在室内水池以溢水法收集真鲷 (Pagrosomusmajor)受精卵 ,并置于不同盐度海水中静水孵化 ,孵出仔鱼以流水培育。设置盐度梯度为 17.0、2 2 .0、2 7.0及自然盐度 3 3 .0 ,水温分别为 19.5~ 2 1.5℃ (孵化 )、2 0 .5~ 2 3 .5℃(培育 )。结果表明∶①真鲷受精卵在自然盐度海水中发育很好 ,孵化率较高 ( 85 .0 %~ 97.0 % ) ,畸形率较低 ( 3 .2 %~ 2 3 .7% ) ;在低盐度条件下静水孵化 ,发育不好 ,孵化率为 4 8.0 %~ 1.0 % ,且盐度越低 ,孵化率也越低。充气孵化时 ,盐度低至 17.0 ,孵化率有时也可达 97.1% ,但畸形率高达 85 .7%~ 10 0 %。②孵化仔鱼中有 2类畸形 ,第 1类畸形表现为身体或尾部弯曲 ,油球位于卵黄囊中部或前部 ,油球数多于 1个 ,盐度越低 ,畸形率越高 ;第 2类畸形表现为仔鱼膜膨大、围心腔扩大 ,这类畸形只出现于低盐度条件下 ,盐度越低 ,畸形率越高 ,且往往与第 1类畸形症状并发。③不同盐度对真鲷仔稚鱼的生长速度没有显著影响 ,各盐度条件仔稚鱼经 3 1d的培养 ,其平均全长为 19.6~ 2 0 .7mm( P >0 .0 5 ) ,没有显著的差别。④海水盐度越低 ,仔稚鱼的存活率越高 ,各组的平均存活率为 ,盐度17.0时 ,3 6.3 % ;盐度 2 2 .0时 ,3 6.2 % ;盐度 2 7.0时 ,2 7.1% ;盐度 3 3 .0时 ,16.3 %。 Pagrosomus major zygotes were collected by overflow method in indoor ponds, incubated in still seawater with different salinity seawater, and hatched larvae were cultured in running water. The salinity gradients were set at 17.0,2.2.0,2 7.0 and natural salinity at 33.0. The water temperature was 19.5-2.15 ℃ (incubation) and 20.5-5.2 ℃ (incubation) respectively. The results showed that: (1) The zygophila eggs developed well in natural salinity seawater with high hatching rate (85.0% -97.0%) and low deformity rate (3.2% -2.37%). Under low salinity conditions, the water still hatched and developed poorly. The hatching rate was 4 8.0% -1.0%, and the lower the salinity, the lower the hatching rate. Inflatable incubation, the salinity as low as 17.0, hatching rate sometimes up to 97.1%, but the deformity rate as high as 85.7% ~ 100%. There were two kinds of deformities in hatching larvae, the first type of deformity manifested as body or tail bending, the oil ball located in the middle or front of the yolk sac, the number of oil balls more than one, the lower the salinity, the higher the deformity rate; the second Class deformities showed laeval inflated membrane, enlarged cardiac cavity, such deformities only appear in low salinity conditions, the lower the salinity, the higher the deformity rate, and often associated with the first category of deformity symptoms. ③The salinity had no significant effect on the growth of juvenile seabream, and the average length of the juvenile juvenile was 31.6-20.7 mm (P> 0.05) No significant difference. The lower the salinity of seawater, the higher the survival rate of juvenile larvae was. The average survival rates of each group were 3 6.3% at salinity 17.0%, 6.22% at salinity 2 2.0% and 2 7.0% , 21 7.1%; salinity 33.0, 16.3%.
其他文献
小学英语学科中关键的要素是英语阅读,可是许多小学生都害怕英语阅读,主要因为英语阅读中有较多的生词和句法。但学习英语的目的并不是记住几个生词,而是培养学生的思维能力,
本文介绍电线管套接螺钉紧固式连接的施工工艺、步骤及优点。
打造精品工程,向用户提供满意工程,历来是我们的行业道德和诚信经营的准则.然而一谈到创优,业内又有人简单地认为,只要肯花钱投入,自然会出精品.施工管理和工程创优是否真的
发热电缆地面辐射供暖是目前电力能源充足地区理想、先进、经济的一种采暖方式。结合工程施工实践,阐述论证了它的结构组成、工作原理、特点,着重论述了施工工艺和操作要点。
文章介绍将某橡胶公司SH20-25/400-AII型锅炉改造成SH25-25-AII型的技术措施及具体施工方法.