Growth performance and yield of hybrid catfish Clarias gariepinus (♂) x Heterobranchus bidorsalis (♀) at various stocking densities

Abstract

The study evaluated effects of varying stocking densities on growth, protein utilization, survival rates and yield of hybrid catfish reared in 1m x 1m x 1m collapsible tarpaulin trough. Fish fry (0.60± 0.01g) were randomly stocked at 25, 50, 75 and 100fish/m³ and fed commercial diet (45% protein) for twelve weeks. At harvest, growth responses and economic performances of fish under various densities were evaluated. Results showed that significant differences (p < 0.05) existed in specific growth rates, gross profit, profit index and economic conversion ratio. Fish stocked at 75 fish/m³ produced the best growth {mean final weight (30.93±1.3g), specific growth rate (4.06±0.07%/day)}; the best protein utilization {food conversion ratio (0.11), protein productive value (1.20±0.02%), protein index (5.34±0.16g/day) and the highest yield {gross profit (₦2931±125/m³), profit index (6.23±0.10) and economic conversion ratio (3.73±0.23).Survival was generally high. The results concluded that hybrid catfish reared in collapsible trough gave the best yield at 75fish/m³.

Keywords: Hybridization, catfish, growth, survival, yield, profit index, economic conversion ratio, nutrient utilization