Growth Performance of Three Nile Tilapia (<i>Oreochromis niloticus</i> L., 1758) Populations in Pond System

Abstract

A 120 days study was conducted to evaluate the growth performances of juvenile Oreochromis niloticus from different lakes (Chamo, Tana and Hashengie) in pond culture system. Fingerlings of average weights 16.7, 15 and 16.9 g for O. niloticus from Lake Chamo, Lake Tana and Lake Hshengie, respectively were stocked at stocking density of 2 fish/m 2 with three replicates each. The treatment groups were fed formulated feed with 29% crude protein at 5% of their body weight per day. Final mean weight of Nile tilapia was highest ( p <0.05) for Lake Chamo (59.6 g) followed by Lake Hashengie (46 g) and Lake Tana (39.4). Daily growth rate (0.4 g per day), Specific growth rate (1.1% per day) and Food conversion ratio (2.5) of O. niloticus from Lake Chamo were significantly ( p <0.05) different from O. niloticus of Lake Tana and Lake Hashengie. On the other hand, O. niloticus from Lake Tana and Lake Hashengie had 0.2 g per day and 0.8% per day daily growth rate and specific growth rate, respectively. O. niloticus from Lake Hashengie was also significantly ( p <0.05) higher in its final mean weight (46 g) and mean weight gain (29.1 g) than O. niloticus from Lake Tana. On the other hand, there was no significant difference ( p <0.05) in the Specific Groth Rate and Food conversion ratio between O. niloticus of Lake Tana and Lake Hashengie. In conclusion, the result of the present study revealed that O. niloticus strain from Lake Chamo showed better growth performance compared to those from Lake Tana and Lake Hashengie. Based on the current result, we recommended O. niloticus strain from Lake Chamo can be considered for tilapia stocking and also for further strain selection programs.