人工驯繁下的长丝裂腹鱼卵及胚胎发育特征观察

Observation of Egg and Embryonic Development of Schizothorax dolichonema Herzenstein by Artificial Breeding and Propagation Technique

【目的】为增殖放流保护雅砻江长丝裂腹鱼资源,需对其野生群体开展移养驯化和人工繁育。【方法】本实验对野生长丝裂腹鱼采用混养和诱食的方式进行驯养,对性腺成熟的亲本采用LHRH-A_2+PG+HCG进行催产,并对其成熟卵、受精卵和胚胎发育特征进行详细观察和描述。【结果】野生长丝裂腹鱼易驯养,且性腺能发育成熟,人工催产效应时间为47.5 h,受精率为75.37%,孵化率为68.54%。成熟卵圆球形、浅黄色、微粘,平均卵径为(2.88±0.29)mm,受精吸水膨胀后为沉性卵,平均卵径为(4.06±0.16)mm。在平均水温10.8℃下,胚胎发育历时204 h 25 min,历经胚盘隆起、卵裂、囊胚、原肠胚、神经胚、器官发育和出膜共7个阶段。【结论】在人工养殖条件下,采取适宜的方法可驯养成熟并人工繁殖野生长丝裂腹鱼成功。在平均水温10.8℃时,其受精卵的孵化时间较长。

【Objective】In order to protect natural resource of Schizothorax dolichonema Herzenstein,it is necessary to breed and propagate wild population successfully.【Method】The wild population was reared to reach sexual maturity by polyculture and feeding.The females were induced to spawn by injection of hormone.The fertilized eggs were obtained and hatched,the embryonic development was observed and described continuously.【Result】The results showed that females injected with LHRH-A2+PG+HCG ovulated successfully,with the response time of 47.5 hours.Mean fertilization rate and mean hatching rate were 75.37%and 68.54%respectively.The egg diameter and egg diameter after inflation of S.dolichonema were(2.88±0.29)mm and(4.06±0.16)mm respectively.Under the water temperature of 10.8℃,the duration of hatching was 252 hours 20 minutes.The embryonic development could be divided into 7 stages,including fertilized egg,cleavage stage,blastula stage,gastrula stage,neurula stage,organogenesis stage and hatching stage.【Conclusion】Under artificial breeding,wild population could reach sexual maturity and propagate successfully.Under the water temperature of 10.8℃,the duration of hatching lasted for a long time.