Effect of broodstock size on egg and larval size and survival of larvae of the African catfish, Clarias gariepinus under laboratory conditions

Abstract

Effect of broodstock size on egg and larval size and survival of larvae of the African catfish Clarias gariepinus was investigated under laboratory conditions for a period of 21 days. Larger broodstock size (600 – 1099 g) produced larger eggs and bigger larvae while smaller broodstock size (300 – 599 g) produced relatively smaller eggs and smaller larvae. The mean size of eggs produced and the size of broodstock was however not significantly different (P > 0.05). In addition, larger eggs resulted in larger fry. The fry size produced by small broodstock size range and the large broodstock size was significantly different (P < 0.05). The survival rate of fry after starvation increased with increase in parent broodstock size. For larger eggs and fry production, broodstock of C. gariepinus, of average size of 500 – 1099 g should be selected for use in fish hatchery operation in Nigeria.


Key Words: Broodstock, Egg, Larvae, Clarias gariepinus


Journal of Aquatic Sciences Vol.19(1) 2004: 1-4