Abstract:
Discogobio multilineatus is a species endemic to the Hongshui River, with a narrow distribution range and scarce wild resources. In order to achieve the scaled production of its larvae and provide technical support for its enhancement and release, the artificially bred
D. multilineatus was intensively cultured and artificially induced to spawn. The fertilized eggs were obtained through dry fertilization, and the embryonic development process was observed. The results show that the absolute fecundity of
D. multilineatus was (415.53±133.27) grains, and the relative fecundity was (18.70±4.67) grains·g
−1. A total of three times of artificial breeding were conducted, with an average spawning rate of (93.12±1.73)%, fertilization rate of (67.03±3.62)%, and hatching rate of (61.34±2.13)%. The fertilized eggs of
D. multilineatus were demersal, non-adhesive, in light blue or pale yellow color, with an eggshell diameter of (2.11±0.04) mm. After absorbing water and swelling, they turned white, with an egg membrane diameter of (3.37±0.09) mm. Under water temperatures of 22−24 ℃, the eggs hatched and eclosed after 67−91 h, with a total hatching and eclosion energy of 1 728.17 ℃·h. The embryonic development went through seven stages and 26 periods, including the blastula stage, cleavage stage, blastocyst stage, gastrula stage, neural plate stage, organogenesis stage, and hatching stage. The newly hatched larvae had a total length of (6.25±0.17) mm and 26 myotomes. This study provides a theoretical basis for the artificial breeding and scaled production of
D. multilineatus.