营养强化和控光控温对大菱鲆亲鱼性腺发育及卵子质量的影响

【目的】总结出一套有效的大菱鲆亲鱼培育技术,为大菱鲆育苗育种工作提供参考。【方法】通过人工控光控温,并投喂冰鲜杂鱼和强化饵料,研究大菱鲆亲鱼培育期间的控光控温和营养强化效果及其对亲鱼性腺发育、卵子质量的影响。【结果】经控光控温和营养强化后,大菱鲆亲鱼性腺开始发育提前67d,性腺发育时间缩短9d,产卵持续时间缩短18d,亲鱼平均产卵量867mL,受精卵活率高达80.1%,受精率67.3%,孵化率61.9%。进一步比较分析,发现控光控温能够使性腺发育时间提前60d,且能在一定程度上缩短性腺发育时间和产卵期;经营养强化后亲鱼产卵量、上浮卵量、上浮率及受精卵活率、孵化率均有显著提高。亲鱼产卵量与体重呈正相关,受精卵活率与孵化率也呈正相关。【结论】大菱鲆亲鱼经营养强化和控光控温后,卵子质量显著提高,性腺发育时间显著提前,实现了反季节产卵。

Effects of nutrition enhancement,light and temperature control on gonad development and ovum quality in Scophthalmus maximus spawner

Objective The purpose of the study was to sum up the culture techniques for turbot spawner and provide references for practitioners involved in turbot breeding. Method Effects of nutrition enhancement and controllable light and temperature on gonad development and egg quality were observed and studied via controlling light and temperature, feeding freezing-fresh fish and nutrition-enhanced bait. ResultThe day of gonad development of these spawners had moved up by 67 days, and the duration of gonad-development had been reduced by 9 days. Egg-laying duration was shortened by 18 days. The average egg amount was 867 mL. The zygote motility rate reached 80.1% with fertility rate of 67.3% and hatching rate of 61.9%. After further analysis, it was found that controlling light and temperature could remarkably move ahead gonad development by 60 days, and cut gonad development duration and egg-laying period to some extent. Nutrition enhancement could dramatically improve spawner fecundity, floating egg amount, floating rate, zygote motility rate and hatching rate. Spawner egg amount and weight as well as zygote motility rate and hatching were positively correlated. Conclusion Egg quality was improved signifi-cantly by nutrition enhancement and light and temperature control. The day of gonad development was moved up greatly, so off season spawning was realized.