Embryonic Development In Clarias gariepinus (Buchell, 1822) Under Laboratory Conditions

Abstract

The embryonic development in Clarias gariepinus was studied under laboratory conditions. The development stages of eggs starting from first cleavage to hatching were examined microscopically. The accurate timing and detailed description of each stage were recorded. Photomicrograph of important stages, segmentation, bastulation, differentiation of embryo and hatching, was taken. The result shows that the bastodisc (polar cap) appeared 35±1 minutes after fertilization. The first cleavage dividing the blastodisc into two bastomeres occurred 15±0.5 minutes after the polar cap formation.The larva emerged from the egg case 22 hours after fertilization at a water temperature of 25.1±1.5^oC. This result will assist in better management of C. gariepinus, enhance their survival to fry and increase the supply of fingerlings in Nigeria.

Keywords: Embryonic development, Clarias gariepinus

Animal Research International Vol. 1 (2) 2004 pp. 81-85