长江上游圆口铜鱼人工繁殖和胚胎发育研究

Study on the Artificial Propagation Andembryonic Development of Coreius guichenoti in the Upper Yangtze River

在不同温度条件下,采用不同剂量的绒毛膜促性腺激素(HCG)、促黄体释放激素类似物A3(LHRHA3)和鲤鱼脑垂体(PG)对性腺发育良好的圆口铜鱼(Coreius guichenoti)进行人工催产,半干法授精,采用锥形底冲水孵化器和孵化框分别置于江水和循环水中进行孵化,利用体视显微镜观察早期发育过程,详细记录各发育阶段的形态特征及发育时序。结果显示:底冲水孵化效果优于孵化框,循环水孵化效果优于江水;圆口铜鱼成熟卵圆形、青灰色,卵径(1.71±0.23)mm,受精卵吸水后迅速膨胀,卵膜外径平均(6.89±0.43)mm。在19.8~20.1℃水温条件下,胚胎发育历时48h+30min,胚胎发育过程可划分为受精卵、卵裂、囊胚、原肠胚、神经胚、器官形成和出膜7个阶段,共27个时期。初孵仔鱼全长(6.45±0.21)mm,眼色素、胸鳍明显,背鳍、鳃弓、肛门原基出现。出膜第4天鳔充气,肠道贯通,开口摄食。研究结果丰富了圆口铜鱼人工繁殖和早期发育资料,可为其人工增殖提供参考。

Different doses of the mature Coreius guichenoti was injected with human chorionic gonadotrophin(HCG),luteinizing hormone releasing hormone A3(LHRH-A3)and carp pituitary gland(PG)for spawning induc⁃ing under various temperatures.The results show that the effect of bottom flush incubator is better than that of incu⁃bator,and the effect of circulating water is better than that of river water.The morphological feature and development characteristics of C.guichenoti was described during the embryo and larvae stage.These results showed that the ripe eggs were oval,steel-gray and(1.71±0.23)mm in diameter,reached the diameter of(6.89±0.43)mm while it is ex⁃panded by adsorption of water.The hatching time lasted for 48.5h with the average water temperature of 19.8~20.1℃.The embryo development could be divided into 27 identical phrases,and 7 main phases,including fertilized egg,cleavage stage,blastula stage,gastrula stage,neural stage,organogenesis stage and hatching stage.The new hatched larvae were(6.45±0.21)mm in total length,and the eye pigment,pectoral fins,caudal fin,gill arch and anus precordium were formed.The formation of digest tract,inflation of air bladder and start to search for feed were ob⁃served in the 4 days post hatching.These results enriched the basic data of the artificial reproduction and early devel⁃opment observation of C.guichenoti which may be useful for the artificial breeding.