Production, Growth and Effect of Varying Stocking Density of Clariobranchus Fry

Hybrid Clariobranchus was produced from clariid catfishes, male Heterobranchus bidorsalis (HB) and female Clarias gariepinus (CG) with Ovaprim hormone (Syndel) to induce maturation. The fertilized eggs were successfully hatched by dry method. Hatchlings were reared to fry on brine shrimp nauplii for 2 weeks. Fingerlings with initial weight/fish (4.70±0.06, 4.52±0.48, 4.78±0.62, 4.62±0.09 g) were stocked in four different treatments and stocking densities of 20, 40, 60, 80 fingerlings, respectively at the nursery phase in the 12 (4x4x2.5 m3) outdoor concrete tanks for 98 days inside the fish net cage (hapa) (1x0.5x0.5 m3) in triplicates for growth study. Fingerlings were fed with 45% compounded feed at 3% body weight twice daily. The weight gained/fish (g) of the fingerlings during the 98 days culture period were significantly different (p<0.05) which varied from 95.66±4.26 and 169.37±7.76 g. The highest weight gained (169.37±7.76 g) was obtained in (T1, 20 fingerlings) with the lowest stocking density. This was significantly different (p<0.05). Feed conversion ratio and feed efficiency were positively correlated with stocking density in Clariobranchus fingerlings. It is advisable to stock the hapa of this size at the maximum of 60 fingerlings m-3 even though, appreciable growth could be adequately be harvested at 80 fingerlings per hapa. The specie (Clariobranchus) being a hybrid of Clarias gariepinus and Heterobranchus bidorsalis had appreciable growth and its high cannibalism traits were controlled with adequate and sufficient feeds.