Effects of intramuscular administration of tamoxifen® on gravid Clarias gariepinus (Burchell, 1822)

Abstract

Three batches of pond raised broodstock of <i>Clarias gariepinus</i> were collected for three (3) months (between September and November 1994). They comprised of ten ready-to-spawn males and ten gravid females whose body weights ranged from 0.20 kg to 0.80 kg. These experimental fish were acclimatized for two to three days in the experimental tanks and were fed with organ meat and supplied with good quality water that was changed every 48 hours. They were starved on the fourth day prior to intramuscular injection of tamoxifen ® on the fifth day. Results revealed that there was no spawning on first and third trials although some golden yellow eggs were released in the second trial among fish injected 10 mg/kg tamoxifen.

Keywords: Artificial spawning, hormone, broodstock, ovulation, spermiation, Clarias gariepinus