CAN OIL PALM KERNEL MEAL BE A COST-EFFECTIVE FEED INGREDIENT FOR IMPROVED GROWTH PERFORMANCE OF FISH FINGERLINGS?
Oil palm kernel meal (PKM) (Elaeis guineensis), an agro-industrial waste and a non-conventional feed ingredient is gaining importance due to its nutrient digestibility (a better growth promoter) and ready availability (lower price) hence, used as an feed ingredient in aqua-diets.
An experiment was conducted for 60 days in 350 L FRP tank on rohu (Labeo rohita) fingerlings (average of 8.6 ± 0.04 cm length and 7.2 ± 0.01g body weight) to determine the effects of dietary incorporation of PKM on growth and physio-metabolic responses of the fish. Five iso-nitrogenous diets namely control (without PKM), T1 (5% PKM), T2 (10% PKM), T3 (15% PKM) and T4 (20% PKM) replacing sunflower oil cake and deoiled rice bran, were prepared and fed twice daily at a rate of 5% body weight. Growth, digestive, metabolic and anti-oxidant enzyme analysis revealed weight gain and specific growth rate (SGR) values showed a gradual increasing trend in T1 (5%), and T2 (10%) groups compared to T3 (15%) and T4 (20%) after 15th day of feeding trial. Feed and protein efficiency and apparent net protein utilization were recorded to be significantly higher in T1 and T2 groups. The digestive (amylase, protease, and lipase) and metabolic enzyme profiles also indicated a significantly (p˃0.05) better response towards 5 and 10% levels of inclusion. Highest superoxide dismutase (SOD) and catalase (CAT) activities were recorded in liver in higher inclusion groups (15 and 20% respectively) which were significantly different (p<0.05) from other groups. Therefore, dietary PKM inclusion level of 10% (T2) improved growth and physio- metabolic performance of the L. rohita fingerlings, indicating that it can be effectively utilized as a cost-effective feed ingredient for optimum growth and metabolic performance of rohu. Thus, this alternative feed source (PKM) containing an economical agro waste by-product, shall help in reducing the feed cost in carp culture operations.
