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首页> 外文期刊>The Progressive Fish-Culturist >Off-season spawning of yellow perch
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Off-season spawning of yellow perch

机译：淡季产卵的黄色鲈鱼

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摘要

The natural thermal and light conditions for 2-year-old broodstock of yellow perch (Perca flavescens) were shifted by 6 months in an effort to change the period of spawning from spring to autumn. The natural photothermal conditions consisted of a chill period of 10deg C and 10 h of light during January-March followed by increases in temperature to 20degree C-22degree C and photoperiod to 15 h light during July-September. The natural spawning of yellow perch occurs in April-May at 12degree C-14degree C and 12 h light. In the present study, the broodstock were maintained at a higher temperature and a longer period of light during September-February (18degree C and 13 h respectively). The photothermal conditions were decreased gradually until June. The chill period (10degree C and 11 h light) was of 60 days duration (June-July) and was followed by gradually increasing water temperature and longer daylight (to 12degree C and 19 h). Following this period, 50% of the females were fully ovulated, and they were stripped or spawned naturally. The males spermiated during the entire shifted spawning period. August-September. The average relative weight of ovulated eggs (as a percentage of female body weight) was 26.6± 10.7. Embryo survival through the eyed stage was 56±24%. A high incidence of larval skeleton abnormalities (45±15%) and a low frequency of swim bladder inflation (44±34%) were observed.
机译：将2岁的黄鲈（Perca flavescens）亲鱼的自然热和光照条件改变了6个月，以期将产卵期从春季改为秋季。自然的光热条件包括1月至3月的10摄氏度的冷风期和10小时的光照，然后在7月至9月的温度升高至20摄氏度至22摄氏度，光照周期为15个小时。黄色鲈鱼的自然产卵发生在4月至5月，温度为12摄氏度至14摄氏度，光照为12小时。在本研究中，亲鱼在9月至2月期间分别处于较高的温度和较长的光照时间（分别为18摄氏度和13个小时）。光热条件逐渐降低，直到六月。寒冷期（10摄氏度和11小时光照）持续时间为60天（6月至7月），随后逐渐升高水温和延长白天（至12摄氏度和19小时）。在此期间之后，有50％的雌性动物完全排卵，然后自然剥离或产卵。在整个转移的产卵期中，雄性会生精。八月九月。排卵卵的平均相对重量（占女性体重的百分比）为26.6±10.7。通过眼睛阶段的胚胎存活率为56±24％。观察到幼虫骨骼异常的发生率很高（45±15％），游泳膀胱充气的发生率较低（44±34％）。

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