Induced spawning and larval rearing studies in buttercatfish Ompok bimaculatus (Bloch, 1794): A candidate species for diversified aquaculture and stock enhancement

The butter catfish Ompok bimaculatus (Bloch, 1794), is a high-value freshwater species, with potential for aquaculture and conservation, though commercial-scale farming remains challenging. This study aimed to develop captive brood stock, induce spawning and evaluate larval growth as well as survival using four distinct diets. Captive brood stock was successfully raised to maturity. Mature females were induced to spawn with WOVA-FH (0.6-1.0 ml kg-1 body weight) and HCG (5,000-10,000 IU kg-1 body weight), while males with WOVA-FH (0.2-0.35 ml kg-1) or HCG (1,500-2,500 IU kg-1). Both hormones gave good results in full ripening of the gonads. WOVA-FH resulted in higher fertilisation (71.26-98.66%) and hatching rates (12.15-36.66%) compared to HCG. Larvae reared for 30 days showed highest growth with Tubifex worms (SGR: 21.09±0.18%), while Artemia nauplii yielded the highest survival (51.11±3.38%). Results highlight the feasibility of induced breeding and the effectiveness of Artemia nauplii for early larval rearing, supporting the species’ potential for aquaculture diversification. Keywords: Butter catfish, Captive brood stock, Fry rearing, HCG, Induced breeding, Ompok bimaculatus, WOVA-FH