白鱚卵各胚胎发生阶段对高温突变、落下冲击和紫外线照射的感受性

本研究将白鱚卵的胚胎发生过程严格区分为27个阶段,并就各不同发生阶段的卵对高温突变、落下冲击和紫外线照射的感受性进行了详细的比较研究,得出了卵裂早期和原肠晚期至胚孔封闭期的卵对高温突变的感受性高;卵裂晚期至胚体出现期,对落下冲击的感受性高;对紫外线照射的感受性,则以胚体出现期为最高。文中同时分析了这种不同环境因素作用于相同鱼卵的同一发生阶段,产生不同影响的原因;建议在鱼类资源保护和鱼苗生产的孵化管理上,应尽量避免感受性较高的相应环境因素变化对鱼卵的影响。

THE EGG SENSITIVITY AT DIFFERENT DEVELOPMENTAL STAGES OF SILLAGO JAPONICA TO THERMAL SHOCK, DROP SHOCK AND ULTRAVIOLET IRRADIATION

In this study, the normal embryonic development of Sillago japonica egg was divided into 27 stages from fertilization to hatching. The sensitivity of eggs to thermal shock, drop shock and ultraviolet irradiation at each developmental stages were compared. Elevation of temperature greatly affects the development particularly during two periods, the early cleavage stage and the stage of late gastrula to closure of blastopore. Drop shock sensitivity during late cleavage to appearance of embryo was higher than that in the other stages. However,in the case of ultraviolet irradiation, the stage of appearance of embryo revealed the highest sensitivity. In this paper, the reasons for the different effects observed at similar developmental stages on the fish egg were described, and suggestion for avoiding these environmental effects on fish eggs at their higher sensitivity developmental stages was also made for the protection of fisheries resource and process of egg incubation.