Abstract

• The present study was conducted to investigate the embryonic developmental stages of Notopterus notopterus in the induced breeding. The breeders of Notopterus notopterus were collected from the Hlawgar fish farm, Yangon Region in September 2020. The injected hormone was buserelin acetate (Suprefact) 10µg per 1kg for the first injection and the second injection was 30 µg per 1kg. The hormone was introduced two times of injection to the female but it was introduced single dose to the male. After 52 hours of injection, female laid eggs on the surfaces of the bricks. The present work showed that the fertilized eggs had yellowish color. The eggs were enveloped with many ridges around the micropyle. The cleavage of fertilized eggs was at 1 hour after laying of the eggs. The early morula (1cell, 2 cells, and 4 cells) stage lasted 2:54 hours and morula (16 cells and 32 cells) stage was found in 4:50 hours. Blastula stages of the dome formation, late blastula and multicellular layer occurred at 6:54, 8:10, and 10:01 hours respectively. The latest cell division of embryonic stage was found at 40:25 hours. The embryonic phase was completed at 50:21 hours. The results of the present work indicated the different phases of embryonic stages of Notopterus notopterus and the time periods of cell division of the eggs.