| 摘要: |
| 于1991年3-5月，在光周期L:D为4:20，8:16，12:12和24:0四种条件下以卤虫无节幼体作饵料，在三角烧瓶中对实验室孵化的罗氏沼虾状幼体进行单只培养，测定各期状幼体的日摄食量和总摄食量，并观察幼体的发育情况。结果表明，随着光照时间的延长，特别是连续照明的条件与最短的光照时间条件相比，幼体的日摄食量增加40％-150％，育成的P1体重增大40％，且育成P1的时间缩短9d，而幼体完成整个变态过程（Z1-P1）的蜕皮次数却相对减少3次。实验证明，连续照明可以促进幼体的生长发育，为最适光周期条件。 |
| 关键词: 罗氏沼虾幼体 摄食量 发育 光周期 |
| DOI： |
| 分类号: |
| 基金项目:赴日留学研究项目 |
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| INFLUENCE OF PHOTOPERIOD ON FOOD CONSUMPTION AND DEVELOPMENT OF MACROBRACHIUM ROSENBERGII LARVAE |
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Lin Xiaotao
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Institute of Hydrobiology,Jinan University,Guangzhou 510632
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| Abstract: |
| The effect of photoperiod on food consumption and development of the larvae of Macrobrachium rasenbergii (De Man) were examined from March to May 1991, in the Tokyo University of Fisheries. After the larvae hatched in laboratory, they were fed with Artemia nauplii and individually reared from the first zoeal stage to postlarval stage under four L:D photoperiods 4:20, 8:16, 12:12 and 24:0. Groups neared under different experimental photoperiods showed significant differences in molting behavior and development rate. The larvae reared under continuous light condition molted at all times in 24h, but most ecdysis (47%) were observed at 12:00-18:00. For the other three groups, ecdysis mostly (93%-97%) occurred at 00:00-06:00 in darkness. There were 10 - 16 instars before metamorphosis in all groups. Short-day larvae tended to pass through an extra stage, e.g. larvae reared at L:D 4:20 passed 3 instars more in average than those reared at 24:0. The intermolt period was similar in each group however, accumulated zoeal duration was 6 - 10d longer in the 4:20 group than in other groups. Food consumption was also significantly different in different photoperiod groups. Daily food consumption was higher with increasing light period, especially in the 24:0 group which was 40% - 150% higher than that of the 4:20 group in the same instars. The total food consumption of all larval development instars in the four groups was in the order 8:16 > 12:12 > 4:20 > 24:0. The larval growth also increased with increasing light period, especially under continuous light condition. Metamorphosed postlarvae growth was 40% higher than that of the 4:20 group if growth is expressed in dry weight. Since higher accumulated food consumption and lower growth was noted in the 4:20 group, their food conversion efficiency was markedly lower than that of the other groups. The study showed that continuous light condition is an important favorable factor accelerating the lawae development. |
| Key words: Macrobrachium rosenbergii larvae, Food consumption, Development, Photoperiod |
