摘要
在 2 5℃、 2 7 5℃、 30℃、 32 5℃和 35℃条件下 ,分别研究了中华鳖 (Trionyxsinensis)卵的孵化和胚胎的发育。卵黄和卵壳的湿重分别占卵重的 85 10 %和 14 90 %,含水量分别为 76 6 3%和 2 1 0 1%。中华鳖胚胎重随孵化时间呈逻辑斯谛曲线增长 ,孵化温度越高 ,胚胎发育速度r越大。 2 5℃～ 30℃的胚胎发育仅表现为‘S 型生长曲线的前、中段 ,在孵化后期发育速度未受到明显的抑制 ,32 5℃和 35℃温度条件下 ,后期发育速度受到了较大的影响。孵出稚鳖湿重和干重均与初始卵重存在极显著的线性相关关系。孵化温度对孵出稚鳖湿重没有显著影响 ,但对孵出稚鳖干重的影响极显著。随孵化温度的升高 ,孵出稚鳖干重呈‘U 形变化 ,在适中温度下 ,胚胎的生长效率最低。卵黄干重随孵化时间呈指数递减 ,温度越高 ,卵黄的利用速度越快。在孵化过程中 ,卵重、卵干重和卵内水总量都随孵化时间的延长、孵化温度的上升而略有下降。孵化期随温度升高呈双曲线缩短 ,其相关关系可用方程I =30 6 +10 9/ (T - 2 2 5 )来表示。中华鳖卵的最适孵化温度在 32 5℃左右 ,胚胎在孵化后期比早期对温度的需求可能要低一些。
We incubated a total of 302 eggs of the Chinese soft shelled turtle, Trionyx sinensis, at 25℃, 27 5℃, 30℃, 32 5℃ and 35℃, respectively, to investigate the effects of temperature on the incubation process and embryonic growth. The experimental eggs were randomly selected at the beginning of the incubation process and measured at intervals of 5～15 d throughout the incubation period, depending on the estimated stage of development. The wet and dry mass of embryos, yolks(or residual yolks) and shells were weighed separately. The wet mass of the yolk and the eggshell were 85 10% and 14 90% of the initial egg weight respectively. Water contents of the egg yolk and the eggshell were 76 63% and 20 10%, respectively. Embryo weights exhibited a sigmoid growth pattern that was significantly affected by incubation temperature. The growth rate of the embryo increased with the incubation temperature. The growth curves of the embryo only represented the initial and middle parts of a typical logistic growth curve, and growth rates were not restrained in the anaphase under lower temperatures(25～30℃). However, when the embryos were incubated at 32 5℃ and 35℃, their growth rates were restrained significantly in the anaphase. Under lower incubation temperatures embryos reached peak growth rates relatively later in the incubation than when incubated at higher temperatures. The hatchlings fresh and dry weights displayed a linear relationship with its initial egg mass. Incubation temperature had no significant effect on hatchlings fresh weight but markedly affected their dry weight. Hatchlings dry weight showed a ‘U type change with increasing temperature. The efficiency of embryo growth was lowest at moderate temperatures. During incubation, the dry weight of the yolk decreased exponentially, while the fresh, dry weights and water mass of the eggs, and the dry weights of the eggshells only decreased slightly.The negative correlation between the duration( I ) and incubation temperatures( T )
出处
《动物学报》
SCIE
CAS
CSCD
北大核心
2002年第6期716-724,共9页
ACTA ZOOLOGICA SINICA
基金
国家自然科学基金资助项目 (3 9670 12 1)
河北省科委 (95 2 2 0 5 0 1D)资助项目~~
关键词
温度
中华鳖卵
孵化
胚胎发育
Chinese soft shelled turtle (Trionyx sinensis), Egg, Incubation, Embryo development, Temperature
