| 摘要: |
| 鱼类的繁殖具有季节性，产卵时间与环境因子的年际节律性变动相适应。红鳍东方鲀属于温带海水鱼类，于每年春末夏初产卵一次。为了探究红鳍东方鲀繁殖周期对不同温光节律变化的响应，在工厂化循环水养殖条件下进行了实验研究。首先，对自然温光季节性变化周期进行等速模拟（光照时间9 h 29 min~14 h 51 min, 水温13.8 ℃~23.7 ℃，12个月一个变化周期，自然组）和2倍加速处理（6个月一个变化周期，加速组），获得了两种不同温光变化模式；然后，将90尾亲鱼分配到自然组和加速组进行培育（2020年6月至2021年7月）。采用体质量、体长和体宽、头宽的跟踪测量方法获得亲鱼在不同季节的估计性腺指数eGSI 和体宽头宽比R，评估亲鱼性腺发育状态，并用人工催产方法确定亲鱼成熟产卵时间。结果发现，两组亲鱼的体质量变化和性腺发育有显著差异，加速组比自然组更早进入体质量的快速增长期和负增长期，加速组的体质量和eGSI、R值在1月前达到峰值，而自然组的在3月才达到峰值；催产试验证明，自然组亲鱼的繁殖时间为3-6月，而加速组亲鱼在1月和7月也能够成功产卵。结果表明，环境温光季节性变化模式能够调控红鳍东方鲀亲鱼性腺发育的启动和成熟产卵时间。在工厂化循环水养殖条件下，繁殖周期温光调控方法简单有效，在红鳍东方鲀全季节繁殖生产中具有良好地应用价值。 |
| 关键词: 红鳍东方鲀(Takifugu rubripes) 繁殖周期 性腺发育 温光调控 模拟季节温光周期 全年繁育 |
| DOI： |
| 分类号: |
| 基金项目:国家重点研发计划课题（2019YFD0900503） |
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| Experimental Study on Photothermal Manipulation of the Reproductive Season in Tiger Puffer Takifugu rubripes |
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SHI Cunzhuo, CHENG Xuewen, LIU Ying, WANG Xiuli, PANG Hongshuai, LIU Qi, TIAN Ye, XIONG Yuyu
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Dalian Ocean University
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| Abstract: |
| The seasonality of reproduction is an important adaptive trait in temperate fish species, and the spawning time is entrained by the cyclical changes occurring in the environment during the year. The control of the internal reproductive processes in captivity through photothermal coordination has been an efficient technique of year-round spawning in fish industrialized recirculation aquaculture for years. The tiger puffer Takifugu rubripe is a commercially important temperate marine fish distributed in the northwestern Pacific, and spawns once a year with spawning season range from late spring (April) to early summer (June). In order to clarify the reproductive cycle of the tiger puffer and its environmental entrainment, natural photothermal cycle (daylight range from 9 h 29 min to 14 h 51 min, water temperature range from 13.8 ℃ to 23.7 ℃，12 months per cycle, natural group) and accelerated photothermal cycle (6 months per cycle, accelerated group) were simulated in hatchery recirculating aquaculture systems, and 90 broodfish were divided into the two groups and their growth performances, gonad development and spawning time were tested from June 2021 to July 2022, respectively. The stages of gonad development were indicated by the eGSI (estimated gonad somatic index) and the BW/HW (ratio of body width and head width). The spawning time was estimated firstly and then confirmed by hormonal induced reproduction. There were significant differences in annual variation pattern of body mass and body width between the two groups. The highest body mass，eGSI and R of the natural group and the accelerated group appeared in March and before January, respectively. Hormonal treatments were applied 6 times for the matured broodfish of the two group. It was confirmed that the spawning time of the natural group was between March to June. The accelerated group ovulated successfully in January and July. The results suggest that the tiger puffer broodfish can respond to the variation of photothermal cycle by adjusting their gonadal development. Photothermal manipulation technique is an effective tool and can be applied for year-round spawning of tiger puffer broodfish. |
| Key words: Tiger puffer Takifugu rubripe Reproductive cycle Gonad development Photothermal manipulation Simulated seasonal photothermal cycle Year-round spawning |