OPTIMUM FEEDING RATES FOR BETTER GROWTH, SURVIVAL, YIELD, AND ECONOMIC RETURN OF MONO-SEX NILE TILAPIA (OREOCHROMIS NILOTICUS) FROM RIVERINE CAGES

Authors: Md. Robiul Awal Hossain Md. Eilious Hosain A. K. M. Nazrul Kabir Md. Niamul Naser

Keywords: Cage culture, riverine aquaculture, Tilapia, GIFT, optimal feeding regime, Grow-out production, sustainable fisheries

Journal: Journal of the Asiatic Society of Bangladesh (Science) - 52(1) - June 2026

Page Numbers: 81-95

Published At: June 2026

DOI: 10.64298/jasbsci.v52i.006

Abstract:

Sustainable tilapia production in cages and its higher economic efficiency depends on optimal feeding strategies. Feed costs in tilapia cage culture account for approximately 60-80% of the total operational expenses. However, studies did not receive much attention on optimizing feeding rates for tilapia culture in floating net cages. This study was conducted to evaluate the effects of different feeding rates on the growth, survival, productivity, and economics of mono-sex Nile tilapia, Oreochromis niloticus, cultured in floating net cages in the Dakatia River system. Three feeding rate treatments (4%, 5%, and 6% of body weight), each in triplicate, were assigned. In total, nine cages (18 m³ each) were installed. Each cage was stocked with 900 mono-sex tilapia fingerlings (50 fingerlings/m3) with a mean initial weight of 20.76 ± 0.80 g. After the 4-month culture period, mean final weight, weight gain, specific growth rate, production, and gross return of tilapia were significantly (p < 0.05) higher in the 5% and 6% feeding treatments than in the 4% feeding treatment. In contrast, feed conversion ratio, net return, and benefit-cost ratio were significantly (p < 0.05) better in the 4% feeding treatment compared with the 5% and 6% feeding treatments. However, tilapia survival was not significantly affected (p > 0.05) in any feeding rate treatments. During the first, second, and third months of culture, tilapia growth in the 5% and 6% feeding treatments did not differ significantly (p > 0.05); however, both treatments showed significantly higher growth (p < 0.05) compared to the 4% feeding treatment. At the fourth month, tilapia growth was significantly higher (p < 0.05) in the 4% feeding treatment compared to the 5% and 6% feeding treatments. Based on this experiment, a feeding rate of 5% of body weight is recommended for the first three months, followed by a reduction to 4% of body weight in the fourth month for commercial tilapia cage culture. The application of these optimal feeding rates in riverine tilapia cage culture can enhance productivity and feed efficiency, leading to higher economic returns for small- to medium-scale commercial farmers.