沙氏下鱵鱼仔鱼的摄食能力和营养代谢  

Feeding ability and nutrient metabolism of the halfbeak (Hyporhamphus sajori) larvae

作　　者：万瑞景 蒙子宁[1] 李显森[1] 

机构地区：[1]农业部海洋渔业资源可持续利用重点开放实验室

出　　处：《动物学报》2003年第4期466-472,共7页ACTA ZOOLOGICA SINICA

基　　金：国家重点基础研究发展规划项目 (No .G19990 43 7)资助~~

摘　　要：20 0 0年 6月 18日 14 :2 0时在 35°0 0′N、 12 1°0 0′E海域利用大型浮游生物网采集了大量的沙氏下鱼天然受精卵 ,将受精卵置于新鲜的海水中进行人工孵化 ,7月 1日 8时仔鱼开始孵出 ,0 5h后收集大约 5 0 0尾初孵仔鱼条进行饥饿试验。在培养水温为 2 4 2～ 2 4 8℃条件下 ,沙氏下鱼仔鱼孵化后 1h就建立起巡游模式 ,4h就具有非常高的初次摄食率和摄食强度 ,仔鱼的混合营养期为 2d ,具有初次摄食能力的时间为 3d ,饥饿不可逆转点发生在孵化后大约 3 5d ,不可逆点 (PNR)期仔鱼没有出现胸角这一形态学特征。沙氏下鱼仔鱼这么短的时间建立巡游模式 ,对仔鱼在混合营养期这一有限的时间内顺利地建立起外源性摄食关系 ,在时间上取得了一定的保障作用 ,对种群的繁衍策略具有一定的生态学意义 ,说明在仔鱼的初次摄食阶段 ,自然海区中适合于仔鱼摄食的饵料生物的种类、分布与数量对其早期的成活是至关重要的。PNR期仔鱼是否具有胸角以及胸角是否为仔鱼的饥饿体征因种而异 ,在渔业资源生态调查的仔鱼样品的鉴别工作中 ,应用仔鱼的胸角鉴别健康仔鱼和饥饿仔鱼时应因种而论.A larger number of fertilized eggs of the halfbeak, Hyporhamphus sajori Temminck et Schlegel, 1846, were collected using a zooplankton horizontal sampling net (mouth diameter 0 8 m, length 2 70 m, mesh size 0 505 mm) in the Yellow Sea (35°00′N, 121°00′E) at 14∶20 on June 18, 2000. The eggs were immediately put in clean water for incubation. The first larvae hatched in the laboratory at eight o'clock, July 1, about 13 days after capture. 30 minutes after hatching, larvae were collected and managed for starvation experiments. The newly hatched larvae were transferred carefully to two green tanks, one for starvation and the other for control. Both tanks were 15 L in volume and were supplied with sand-filtered water at 24 2-24 8℃ and salinity of 30 00-32 00. Each tank contained about 500 larvae. Water in the starvation tank was re-filtered with absorbent cotton to eliminate any possible food organisms. One third of the water in each tanks was changed every day during the experiments. About 20 individuals from the starved group of larvae were removed from the tank after four hours of starvation and again at nine o'clock on the following day. These larvae were put in a 400 ml beaker and fed with live food organisms to estimate the effects of starvation on their initial feeding rate (IFR); the number of individuals with food organisms in their alimentary tracts as a percentage of the total number of individuals checked. Larvae removed four hours after starvation were fed rotifers,Brachionus plicatilis O. F. Müller, 1786 (20 ind·ml -1), enhanced with green alga, Chlorella sp., and those removed the following days were fed rotifers (15 ind·ml -1) and Brine shrimp (Artemia salina L.) nauplii (10 ind·ml -1). Half an hour after feeding, the larvae were killed with benzocaine (200 μg·ml -1) and examined under a microscope to determine whether there were food organisms in their digestive tracts. The point of non-return (PNR) was determined as the day when IFR decreased to half its maximum, based on t

关 键 词：沙氏下触鱼 仔鱼 摄食能力 营养代谢 胸角 颌针鱼目 

分 类 号：Q493[生物学—生理学]