UPAYA PEMBUAHAN TELUR LELE LOKAL (Clarias batrachus)PADA BERBAGAI PASCA OVULASI VIABILITY OF ASIAN CATFISH (Clarias batrachus) EGGS FERTILIZED AT VARIOUS OVULATION INTERVAL

ABSTRACT: The purpose of this research was to determine the viability of Asian catfish (Clarias batrachus) eggs which were fertilized at various post ovulation periods. Initially, the gravid female broodstocks were stimulated by injection of LHRHa hormone. The broodstocks then were stripped by gently pushing from abdomen to the genital pore to expel some eggs (around 1-2 ml). Eggs subsequently were fertilized with sperms, which were prepared before. Then, the fertilized eggs were distributed into a small scoop net which were immersed in the hatching tank. Those procedures were done every 2 hours and completed in 12 hours after ovulation. The experiment was done by completely randomized design with three replicates Result of the research showed that fertilization of Asian catfish eggs could be done until 12 hour after ovulation.The highest percentage of embryo development was found at 8 hours delaying of fertilization and hatching rate as well as. Dissolved oxygen concentration was decreased drastically at the time of eggs hatching which lead to kill almost all larvae. Further experiments are needed to find out an oxygen consumption of eggs and longer delaying of fertilization. Key words : Clarias batrachus, ovulation, and LHRH