山瑞鳖产卵与孵化研究

Studies on laying and hatching eggs of Palea steindachneri

1997年对山瑞鳖的产卵和孵化进行了研究 .结果表明 :人工养殖的山瑞鳖产卵期为每年的 5～ 8月份 ,6～ 7月份为产卵高峰期。产卵次数 1年 1次 ,每窝产卵数量 2～ 2 8只不等 ,最多出现为 11只 /窝 ,平均 11.0 2只 /窝 全年卵受精率 6 4 .77% 山瑞鳖卵平均重 9.58g 受精卵在产出 8～2 0h出现白色的受精斑点 ,并随时间的延长亮斑不断扩大 山瑞鳖卵在自然条件下孵化时 ,需时 70～ 80d ;恒温孵化时 ,随孵化温度的上升 ,孵化所需时间减少 ,积温减少 ,但在 33℃时 ,胚胎在发育早期死亡 ,无鳖孵出 孵化温度为 2 8℃时 ,孵化率最高 (95% )

The laying and hatching of eggs of Palea steindachneri were studied in Guangzhou in 1997, resulting in the following generalizations. The mature female spawns once a year in May to August,chiefly in June and July.Generally it lays 6～13 eggs,varying individually from a maximum of 28 eggs to a minimum of 2 eggs, with a mean of about 11 eggs.The average weight for one egg evaluated from 300 is 9.58g. White spots emerge on the surface of fertilized eggs 8～20 hour after they are laid.These spots become larger as time goes on.The overall rate of fertilization is 64.77%(2212/3415) in 1997. In natural,the incubation period lasts 70～80 days;under constant temperatures, the higher the temperature, the shorter the incubation period.of 4 experimental groups, the incubation rate of the 28℃ group is highest (95%). at 33℃ all embryoes die. In the paper, we found weight of child Palea steindachneri was relative to size of eggs. [