摘要
用扫描电镜技术观察了中华绒螯蟹正常附着胚胎及流产胚胎的结构特点。结果表明,受精卵从生殖孔排出15min后,孵化室中的孵化液体积增大,使胚胎浸没在孵化液中,胚胎表面具有粘性;产卵后30min,卵柄初步形成;80～140min后卵柄完全形成,胚胎牢固地粘附在携卵绒毛上。正常胚胎的卵柄高度扭曲,上有很多毛状物,同时携卵刚毛上有很多粘液;流产胚胎的卵柄上无毛状物,但卵柄及胚胎表面有许多寄生物附着。携卵刚毛上的粘液及卵柄上的毛状物可能和胚胎附着有关;而胚胎表面寄生物的活动,可能使胚胎外被、卵柄以及卵索的结构发生变化,增加了胚胎之间的摩擦,进而胚胎呼吸困难,以致死亡和流产。
The structural features of normal and abnormal embryo attachment systems of the Chinese mitten crab Eriocheir sinensis were investigated by scanning electron microscopy. The results showed that the volume of in cubation fluid inthe brooding chamber increased 15 minutes after egg-laying, immersing the embryos in the incubation fluid and thus the egg envelop became very sticky immediately. The egg stalk was largely formed within 30 minutes and completed within 80 to 140 minutes after egg-laying, so that the egg envelop became strongly adherent to the ovigerous hairs. In normal embryos, the egg stalks were highly twisted and the embryos were attached to the ovigerous hair by the egg stalk or funiculus. Many villiform were found on egg stalks and a lot of mucus was also found on the ovigerous seta. In abnormal egg stalks, villiform were never found, though numerous epibionts were attached to the embryo surface and egg stalk. The mucus of ovigerous hair and the villiform of egg stalks may contribute to egg attachment. Because of the epibionts the structure of egg investment coat egg stalk and funiculus were changed, enhancing the attrition between embryos and making embryo respiration difficult. The death and loss of embryos occur because of the above reasons.
基金
温州市科技局基金资助项目(N2000A26)
温州市"551人才"基金项目
乐清市科技局基金资助项目(02N043)
关键词
中华绒螯蟹
流产
扫描电镜
胚胎附着
Eriocheir sinensis
Embryo loss
Scanning electron microscopy
Embryo attachment
