泥鳅早期形态发育研究

【目的】为了解泥鳅仔、稚鱼生长发育规律，同时为规模化苗种培育工作提供基础数据。【方法】通过对0~23日龄的泥鳅仔稚鱼连续取样，系统观察了泥鳅仔稚鱼各发育分期的形态特征和发育时间。【结果】研究结果表明，在水温(19.5~22)℃下，泥鳅胚胎发育时间需要24~28 h。初孵仔鱼平均体长为3.04 mm，鱼体透明，全身无黑色素，口和消化管均未形成；初孵仔鱼至孵化后6日龄为卵黄囊期仔鱼，4日龄仔鱼开口，仔鱼进入混合营养期；7~9日龄为前弯曲期仔鱼，7日龄仔鱼卵黄囊吸收完毕，此时完全进入外源营养期；10~14日龄为弯曲期仔鱼；15~22日龄为后弯曲期仔鱼；至23日龄，出现细小圆鳞，已与成鱼具有相似的外观和生活习性，此时进入稚鱼期。【结论】研究泥鳅早期形态发育将为泥鳅自然资源繁殖保护和养殖业苗种培育提供理论依据。

Study on the developmental and morphological characters in Missgurnus arguillicaudatus larvae

In order to understand the growth and development of the juvenile of the mud loach and provide basic data for large-scale larval rearing. The morphological development of larval and juvenile mud loach, Missgurnus Arguillicaudatus was examined in a hatchery-reared series. The results showed that when the water temperature ranged between 19.5-22.0℃, the embryonic development took 24-28 hours. The average standard body length of newly hatched larva was 3.04 mm, the body was transparent without any pigments. The mouth and gut haven＇t formed in the newly hatched larvae. The mouth opened 4 days after hatching and entered a mixed feeding stage. It took 6 days for larva to develop into preflexion larva stage, the yolk is absorbed completely and exdoerophic stage begins. Notochord flexion started on the 10th day. On the 15th day, the hypurals were completed and entered the postflexion larva stage. Transformation from the larval to the juvenile stage occurred on 23th day, the round scales had been formed and the juvenile fish had basic external shape and habits of adult fish. This study was significantly important in conservation and seed breeding of Missgurnus Arguillicaudatus.