EFFECT OF DIFFERENT STOCKING TIME ON GROWTH AND SURVIVAL OF SEX-REVERSED NILE TILAPIA (Oreochromis niloticus) FINGERLINGS IN A POND-BASED HAPA SYSTEM

Abstract

Oreochromis niloticus is one of the most cultivated tropical finfish in the world, and it is the third most utilized commodity in the Philippines. Even though tilapia is known to be a resilient and hardy fish species, Filipino fish farmers are still experiencing 20 to 40% post-stocking mortalities, which adversely affects their profitability. Research on the effect of stocking time to the survival and growth rate is beneficial to solve the said problem.

Results of this study showed that tilapia fingerlings stocked at 7:00 AM had a lower survival rate of 78.76±2.12% in comparison with the fish stocked at 12:00 NN with 91.30±0.82% and those stocked at 5:00 PM with 96.52±2.67% (P > 0.05). In contrast, there is no significant difference for the growth rate among all the treatments after the 30-day culture period in the hapas (P > 0.05).

In conclusion, early morning stocking time negatively impacts the survivability of the fish due to lower DO concentration and abrupt temperature change in pond water during dawn, which causes a higher level of stress to the fish, while the time of stocking does not affect the specific growth rate of the fish.