摘要: |
在水温18℃~19℃条件下,采用实验生态学方法研究了饥饿对黑棘鲷(Acanthopagrus schlegelii)仔鱼存活、生长发育及行为学特征的影响。通过测定仔鱼的初次摄食率和饥饿不可逆点(PNR),确定了初次投喂的最佳时间。结果显示,黑棘鲷仔鱼3日龄开口摄食,4日龄卵黄囊消失,6日龄油球消失,混合营养期仅3 d,属容易遭受饥饿胁迫的鱼类。仔鱼开口时初次摄食率仅为30%,之后迅速提高,至5日龄达到最高的90%,之后逐渐下降,7日龄降至45%,到达PNR。饥饿组仔鱼在6日龄后开始出现生理性萎缩,全长与对照组相比差异显著(P<0.05),进入PNR后,仔鱼活动能力显著下降,身体出现扭曲、畸形,死亡率急剧升高,至10日龄全部死亡。黑棘鲷仔鱼耐受饥饿能力较弱,建议开始投饵的最适时机为仔鱼开口后的4 d内。 |
关键词: 黑棘鲷 仔鱼 饥饿 不可逆点 |
DOI:10.19663/j.issn2095-9869.20190104001 |
分类号: |
基金项目: |
|
Experimental Starvation of Acanthopagrus schlegelii Larvae, and Definition of the Point of No Return |
YANG Yukai1,2, LIN Heizhao1,2, WANG Zhiyong3,4, XIE Yangjie3,4, GUO Yihui1,2, HUANG Xiaolin1,2, LI Tao1,2
|
1.Key Laboratory of South China Sea Fishery Research Exploitation & Utilization, Ministry of Agriculture and Rural Affairs;2.South China Sea Fisheries Research Institute, Chinese Academy of Fishery Sciences, Guangzhou 510300;3.Key Laboratory of Healthy Mariculture for the East China Sea, Ministry of Agriculture and Rural Affairs;4.Fisheries College, Jimei University, Xiamen 361021
|
Abstract: |
The potential effects of starvation on the growth, feeding, and survival of Acanthopagrus schlegelii larvae were investigated at a water temperature of 18℃~19℃ by using ecological experimental methods. Along with the detection of the initial feeding rate and the point of no return (PNR), the optimum initial feeding time of the larvae were also ascertained. The results showed that larvae started feeding on the third day post hatching (dph), and the yolk sac and the oil globule disappeared at 4 DPH and 6 dph, respectively, which suggested that the duration of the mixotrophic stage was about 3 days and larvae were vulnerable to starvation. When the fish opened their mouths, the initial feeding rate was only 30%, which then rapidly increased to the highest level of 90% at 5 dph, after which it gradually declined to 45% at 7 dph, which denoted the PNR. Significant variation was found between the starved and control groups after 6 dph (P<0.05). Reduced mobility, distorted or deformed bodies, and increased mortality were observed in the starved larvae after the PNR. All the starved larvae died before 10 DPH. In brief, our study suggested that A. schlegelii larvae were vulnerable to starvation and the optimum initial feeding time of the larvae was within 4 days after their mouths opened. |
Key words: Acanthopagrus schlegelii Larvae Starvation Point of no return (PNR) |