Spawning and Larval Development of the African Mudfish (Heterotis niloticus) Under Controlled Aquaculture Conditions in Ogun State

This study investigates the spawning induction and larval development of Heterotis niloticus under controlled aquaculture conditions in Ogun State, located in Nigeria's South West geopolitical zone. Heterotis niloticus is a large, fast-growing fish with high market value in Nigeria, but its culture is constrained by limited domestication of the spawning and larval rearing stages. Ovulation was induced in four females using combined synthetic hormone injection (LHRH analogue and domperidone). Fertilisation was conducted using milt from three males by dry stripping. Fertilised eggs were incubated in circular hatching jars under constant aeration. Larvae were reared in 500-litre tanks with zooplankton as initial starter feed transitioning to finely powdered formulated feed. Developmental stages were documented photographically at 12-hour intervals. Mean latency period to ovulation was 12.4 hours at 27 degrees Celsius. Fertilisation rate averaged 78.3 percent and hatching rate 65.4 percent. Larvae were free-swimming at 72 hours post-hatching. Survival to day 30 larvae was 44 percent on zooplankton feeding and 27 percent on formulated feed alone, highlighting the importance of live food in early rearing. The study demonstrates the feasibility of controlled Heterotis niloticus propagation in Ogun State and recommends investment in zooplankton culture systems as a prerequisite for commercial-scale larval rearing. Keywords: Heterotis niloticus, spawning, larval development, aquaculture, Ogun State.