Growth and quality of Nile Tilapia fingerling product in domestic sewage water treated

Abstract

This paper aims to assess the feasibility of the use of domestic sewage to produce Nile Tilapia fingerling, Oreochromis niloticus. Three fish-ponds with a 50 m³ volume have been used, one of them is supplied with well water and the other two with treated domestic sewage coming from a system of stabilization ponds. In the two last ponds, the effect of the additional aeration utilizing a suction aerator was compared. All the fish-ponds were populated by tilapia fingerling, sexually reverted to males, with mean weight of 1.5 g, storage density of 12 fingerling/m² .The experiment lasted for 49 days, and the fingerling should get to the final mean weight of 40.0 g (standard mean weight for the storage in net tanks used in the regional fish culture). The growth parameters have been analyzed according to the weight and length and the levels of contamination by pathogens in the muscles, visceral organs and skin of the fishes. As a conclusion, the feasibility of the use of domestic sewage to produce Nile tilapia fingerling treated in a system of stabilization ponds with the use of additional mechanic aeration. It has also been observed that, in the harvest, the contamination levels in the fish are within the limits allowed by the current sanitary legislation.